msgid ""
msgstr ""
"Project-Id-Version: PACKAGE VERSION\n"
-"POT-Creation-Date: 2012-04-25 05:36+0900\n"
+"POT-Creation-Date: 2015-02-04 23:32+0900\n"
"PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
"Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
"Language-Team: LANGUAGE <LL@li.org>\n"
msgstr ""
#. type: TH
-#: build/C/man2/alloc_hugepages.2:25 build/C/man2/cacheflush.2:24 build/C/man2/fallocate.2:8 build/C/man2/madvise.2:35 build/C/man3/mallopt.3:24 build/C/man2/mlock.2:27 build/C/man2/mmap.2:40 build/C/man2/mmap2.2:29 build/C/man2/mprotect.2:32 build/C/man2/mremap.2:31 build/C/man2/msync.2:25 build/C/man2/posix_fadvise.2:27 build/C/man2/readahead.2:28 build/C/man2/remap_file_pages.2:26 build/C/man3/shm_open.3:26 build/C/man7/shm_overview.7:27 build/C/man2/shmctl.2:43 build/C/man2/shmget.2:36 build/C/man2/shmop.2:39 build/C/man2/subpage_prot.2:28 build/C/man2/sync_file_range.2:30
+#: build/C/man2/alloc_hugepages.2:25 build/C/man2/cacheflush.2:25 build/C/man2/fallocate.2:11 build/C/man2/madvise.2:35 build/C/man3/mallinfo.3:26 build/C/man3/malloc_stats.3:26 build/C/man3/malloc_trim.3:26 build/C/man3/mallopt.3:26 build/C/man2/mlock.2:26 build/C/man2/mmap.2:40 build/C/man2/mmap2.2:29 build/C/man2/mprotect.2:39 build/C/man2/mremap.2:30 build/C/man2/msync.2:25 build/C/man2/posix_fadvise.2:28 build/C/man2/readahead.2:28 build/C/man2/remap_file_pages.2:28 build/C/man3/shm_open.3:26 build/C/man7/shm_overview.7:27 build/C/man2/shmctl.2:45 build/C/man2/shmget.2:38 build/C/man2/shmop.2:41 build/C/man2/subpage_prot.2:30 build/C/man2/sync_file_range.2:30 build/C/man2/memfd_create.2:21
#, no-wrap
msgid "Linux"
msgstr ""
#. type: TH
-#: build/C/man2/alloc_hugepages.2:25 build/C/man3/alloca.3:41 build/C/man2/cacheflush.2:24 build/C/man2/fallocate.2:8 build/C/man2/madvise.2:35 build/C/man3/malloc_hook.3:6 build/C/man3/mallopt.3:24 build/C/man2/mlock.2:27 build/C/man2/mmap.2:40 build/C/man2/mmap2.2:29 build/C/man2/mprotect.2:32 build/C/man2/mremap.2:31 build/C/man2/msync.2:25 build/C/man3/mtrace.3:23 build/C/man2/posix_fadvise.2:27 build/C/man3/posix_fallocate.3:23 build/C/man3/posix_memalign.3:28 build/C/man2/readahead.2:28 build/C/man2/remap_file_pages.2:26 build/C/man3/shm_open.3:26 build/C/man7/shm_overview.7:27 build/C/man2/shmctl.2:43 build/C/man2/shmget.2:36 build/C/man2/shmop.2:39 build/C/man2/subpage_prot.2:28 build/C/man2/sync_file_range.2:30
+#: build/C/man2/alloc_hugepages.2:25 build/C/man3/alloca.3:43 build/C/man2/cacheflush.2:25 build/C/man2/fallocate.2:11 build/C/man2/madvise.2:35 build/C/man3/mallinfo.3:26 build/C/man3/malloc_get_state.3:25 build/C/man3/malloc_hook.3:10 build/C/man3/malloc_info.3:25 build/C/man3/malloc_stats.3:26 build/C/man3/malloc_trim.3:26 build/C/man3/malloc_usable_size.3:25 build/C/man3/mallopt.3:26 build/C/man3/mcheck.3:25 build/C/man2/mlock.2:26 build/C/man2/mmap.2:40 build/C/man2/mmap2.2:29 build/C/man2/mprotect.2:39 build/C/man2/mremap.2:30 build/C/man2/msync.2:25 build/C/man3/mtrace.3:25 build/C/man2/posix_fadvise.2:28 build/C/man3/posix_fallocate.3:25 build/C/man3/posix_memalign.3:29 build/C/man2/readahead.2:28 build/C/man2/remap_file_pages.2:28 build/C/man3/shm_open.3:26 build/C/man7/shm_overview.7:27 build/C/man2/shmctl.2:45 build/C/man2/shmget.2:38 build/C/man2/shmop.2:41 build/C/man2/subpage_prot.2:30 build/C/man2/sync_file_range.2:30 build/C/man2/memfd_create.2:21 build/C/man2/s390_pci_mmio_write.2:25
#, no-wrap
msgid "Linux Programmer's Manual"
msgstr ""
#. type: SH
-#: build/C/man2/alloc_hugepages.2:26 build/C/man3/alloca.3:42 build/C/man2/cacheflush.2:25 build/C/man2/fallocate.2:9 build/C/man2/madvise.2:36 build/C/man3/malloc_hook.3:7 build/C/man3/mallopt.3:25 build/C/man2/mlock.2:28 build/C/man2/mmap.2:41 build/C/man2/mmap2.2:30 build/C/man2/mprotect.2:33 build/C/man2/mremap.2:32 build/C/man2/msync.2:26 build/C/man3/mtrace.3:24 build/C/man2/posix_fadvise.2:28 build/C/man3/posix_fallocate.3:24 build/C/man3/posix_memalign.3:29 build/C/man2/readahead.2:29 build/C/man2/remap_file_pages.2:27 build/C/man3/shm_open.3:27 build/C/man7/shm_overview.7:28 build/C/man2/shmctl.2:44 build/C/man2/shmget.2:37 build/C/man2/shmop.2:40 build/C/man2/subpage_prot.2:29 build/C/man2/sync_file_range.2:31
+#: build/C/man2/alloc_hugepages.2:26 build/C/man3/alloca.3:44 build/C/man2/cacheflush.2:26 build/C/man2/fallocate.2:12 build/C/man2/madvise.2:36 build/C/man3/mallinfo.3:27 build/C/man3/malloc_get_state.3:26 build/C/man3/malloc_hook.3:11 build/C/man3/malloc_info.3:26 build/C/man3/malloc_stats.3:27 build/C/man3/malloc_trim.3:27 build/C/man3/malloc_usable_size.3:26 build/C/man3/mallopt.3:27 build/C/man3/mcheck.3:26 build/C/man2/mlock.2:27 build/C/man2/mmap.2:41 build/C/man2/mmap2.2:30 build/C/man2/mprotect.2:40 build/C/man2/mremap.2:31 build/C/man2/msync.2:26 build/C/man3/mtrace.3:26 build/C/man2/posix_fadvise.2:29 build/C/man3/posix_fallocate.3:26 build/C/man3/posix_memalign.3:30 build/C/man2/readahead.2:29 build/C/man2/remap_file_pages.2:29 build/C/man3/shm_open.3:27 build/C/man7/shm_overview.7:28 build/C/man2/shmctl.2:46 build/C/man2/shmget.2:39 build/C/man2/shmop.2:42 build/C/man2/subpage_prot.2:31 build/C/man2/sync_file_range.2:31 build/C/man2/memfd_create.2:22 build/C/man2/s390_pci_mmio_write.2:26
#, no-wrap
msgid "NAME"
msgstr ""
msgstr ""
#. type: SH
-#: build/C/man2/alloc_hugepages.2:28 build/C/man3/alloca.3:44 build/C/man2/cacheflush.2:27 build/C/man2/fallocate.2:11 build/C/man2/madvise.2:38 build/C/man3/malloc_hook.3:11 build/C/man3/mallopt.3:27 build/C/man2/mlock.2:30 build/C/man2/mmap.2:43 build/C/man2/mmap2.2:32 build/C/man2/mprotect.2:35 build/C/man2/mremap.2:34 build/C/man2/msync.2:28 build/C/man3/mtrace.3:26 build/C/man2/posix_fadvise.2:30 build/C/man3/posix_fallocate.3:26 build/C/man3/posix_memalign.3:31 build/C/man2/readahead.2:31 build/C/man2/remap_file_pages.2:29 build/C/man3/shm_open.3:29 build/C/man2/shmctl.2:46 build/C/man2/shmget.2:39 build/C/man2/shmop.2:42 build/C/man2/subpage_prot.2:31 build/C/man2/sync_file_range.2:33
+#: build/C/man2/alloc_hugepages.2:28 build/C/man3/alloca.3:46 build/C/man2/cacheflush.2:28 build/C/man2/fallocate.2:14 build/C/man2/madvise.2:38 build/C/man3/mallinfo.3:29 build/C/man3/malloc_get_state.3:28 build/C/man3/malloc_hook.3:15 build/C/man3/malloc_info.3:28 build/C/man3/malloc_stats.3:29 build/C/man3/malloc_trim.3:29 build/C/man3/malloc_usable_size.3:28 build/C/man3/mallopt.3:29 build/C/man3/mcheck.3:28 build/C/man2/mlock.2:29 build/C/man2/mmap.2:43 build/C/man2/mmap2.2:32 build/C/man2/mprotect.2:42 build/C/man2/mremap.2:33 build/C/man2/msync.2:28 build/C/man3/mtrace.3:28 build/C/man2/posix_fadvise.2:31 build/C/man3/posix_fallocate.3:28 build/C/man3/posix_memalign.3:32 build/C/man2/readahead.2:31 build/C/man2/remap_file_pages.2:31 build/C/man3/shm_open.3:29 build/C/man2/shmctl.2:48 build/C/man2/shmget.2:41 build/C/man2/shmop.2:44 build/C/man2/subpage_prot.2:33 build/C/man2/sync_file_range.2:33 build/C/man2/memfd_create.2:24 build/C/man2/s390_pci_mmio_write.2:29
#, no-wrap
msgid "SYNOPSIS"
msgstr ""
msgstr ""
#. type: SH
-#: build/C/man2/alloc_hugepages.2:38 build/C/man3/alloca.3:48 build/C/man2/cacheflush.2:33 build/C/man2/fallocate.2:19 build/C/man2/madvise.2:50 build/C/man3/malloc_hook.3:29 build/C/man3/mallopt.3:31 build/C/man2/mlock.2:40 build/C/man2/mmap.2:52 build/C/man2/mmap2.2:39 build/C/man2/mprotect.2:41 build/C/man2/mremap.2:43 build/C/man2/msync.2:32 build/C/man3/mtrace.3:32 build/C/man2/posix_fadvise.2:49 build/C/man3/posix_fallocate.3:44 build/C/man3/posix_memalign.3:83 build/C/man2/readahead.2:38 build/C/man2/remap_file_pages.2:37 build/C/man3/shm_open.3:41 build/C/man7/shm_overview.7:30 build/C/man2/shmctl.2:54 build/C/man2/shmget.2:47 build/C/man2/shmop.2:51 build/C/man2/subpage_prot.2:36 build/C/man2/sync_file_range.2:41
+#: build/C/man2/alloc_hugepages.2:38 build/C/man3/alloca.3:50 build/C/man2/cacheflush.2:34 build/C/man2/fallocate.2:22 build/C/man2/madvise.2:50 build/C/man3/mallinfo.3:33 build/C/man3/malloc_get_state.3:36 build/C/man3/malloc_hook.3:33 build/C/man3/malloc_info.3:34 build/C/man3/malloc_stats.3:33 build/C/man3/malloc_trim.3:33 build/C/man3/malloc_usable_size.3:32 build/C/man3/mallopt.3:33 build/C/man3/mcheck.3:40 build/C/man2/mlock.2:39 build/C/man2/mmap.2:54 build/C/man2/mmap2.2:39 build/C/man2/mprotect.2:48 build/C/man2/mremap.2:42 build/C/man2/msync.2:32 build/C/man3/mtrace.3:34 build/C/man2/posix_fadvise.2:50 build/C/man3/posix_fallocate.3:46 build/C/man3/posix_memalign.3:84 build/C/man2/readahead.2:38 build/C/man2/remap_file_pages.2:39 build/C/man3/shm_open.3:41 build/C/man7/shm_overview.7:30 build/C/man2/shmctl.2:56 build/C/man2/shmget.2:49 build/C/man2/shmop.2:53 build/C/man2/subpage_prot.2:41 build/C/man2/sync_file_range.2:41 build/C/man2/memfd_create.2:28 build/C/man2/s390_pci_mmio_write.2:39
#, no-wrap
msgid "DESCRIPTION"
msgstr ""
msgid ""
"The system calls B<alloc_hugepages>() and B<free_hugepages>() were "
"introduced in Linux 2.5.36 and removed again in 2.5.54. They existed only "
-"on i386 and ia64 (when built with B<CONFIG_HUGETLB_PAGE>). In Linux 2.4.20 "
+"on i386 and ia64 (when built with B<CONFIG_HUGETLB_PAGE>). In Linux 2.4.20, "
"the syscall numbers exist, but the calls fail with the error B<ENOSYS>."
msgstr ""
msgstr ""
#. type: SH
-#: build/C/man2/alloc_hugepages.2:109 build/C/man3/alloca.3:58 build/C/man2/cacheflush.2:52 build/C/man2/fallocate.2:109 build/C/man2/madvise.2:250 build/C/man3/mallopt.3:377 build/C/man2/mlock.2:117 build/C/man2/mmap.2:373 build/C/man2/mmap2.2:54 build/C/man2/mprotect.2:72 build/C/man2/mremap.2:128 build/C/man2/msync.2:68 build/C/man2/posix_fadvise.2:86 build/C/man3/posix_fallocate.3:64 build/C/man3/posix_memalign.3:141 build/C/man2/readahead.2:65 build/C/man2/remap_file_pages.2:122 build/C/man3/shm_open.3:169 build/C/man2/shmctl.2:272 build/C/man2/shmget.2:178 build/C/man2/shmop.2:169 build/C/man2/subpage_prot.2:61 build/C/man2/sync_file_range.2:141
+#: build/C/man2/alloc_hugepages.2:109 build/C/man3/alloca.3:60 build/C/man2/cacheflush.2:53 build/C/man2/fallocate.2:228 build/C/man2/madvise.2:268 build/C/man3/malloc_get_state.3:61 build/C/man3/malloc_info.3:48 build/C/man3/malloc_trim.3:51 build/C/man3/malloc_usable_size.3:40 build/C/man3/mallopt.3:379 build/C/man3/mcheck.3:129 build/C/man2/mlock.2:116 build/C/man2/mmap.2:375 build/C/man2/mmap2.2:54 build/C/man2/mprotect.2:77 build/C/man2/mremap.2:127 build/C/man2/msync.2:68 build/C/man2/posix_fadvise.2:87 build/C/man3/posix_fallocate.3:66 build/C/man3/posix_memalign.3:142 build/C/man2/readahead.2:66 build/C/man2/remap_file_pages.2:132 build/C/man3/shm_open.3:171 build/C/man2/shmctl.2:283 build/C/man2/shmget.2:183 build/C/man2/shmop.2:168 build/C/man2/subpage_prot.2:66 build/C/man2/sync_file_range.2:141 build/C/man2/memfd_create.2:126 build/C/man2/s390_pci_mmio_write.2:68
#, no-wrap
msgid "RETURN VALUE"
msgstr ""
msgstr ""
#. type: SH
-#: build/C/man2/alloc_hugepages.2:118 build/C/man2/cacheflush.2:58 build/C/man2/fallocate.2:112 build/C/man2/madvise.2:257 build/C/man3/mallopt.3:382 build/C/man2/mlock.2:123 build/C/man2/mmap.2:390 build/C/man2/mmap2.2:61 build/C/man2/mprotect.2:79 build/C/man2/mremap.2:136 build/C/man2/msync.2:73 build/C/man2/posix_fadvise.2:89 build/C/man3/posix_fallocate.3:70 build/C/man3/posix_memalign.3:155 build/C/man2/readahead.2:71 build/C/man2/remap_file_pages.2:129 build/C/man3/shm_open.3:178 build/C/man2/shmctl.2:294 build/C/man2/shmget.2:182 build/C/man2/shmop.2:183 build/C/man2/subpage_prot.2:66 build/C/man2/sync_file_range.2:147
+#: build/C/man2/alloc_hugepages.2:118 build/C/man2/cacheflush.2:59 build/C/man2/fallocate.2:235 build/C/man2/madvise.2:275 build/C/man3/malloc_info.3:55 build/C/man3/malloc_trim.3:56 build/C/man3/mallopt.3:384 build/C/man2/mlock.2:122 build/C/man2/mmap.2:392 build/C/man2/mmap2.2:61 build/C/man2/mprotect.2:84 build/C/man2/mremap.2:135 build/C/man2/msync.2:73 build/C/man2/posix_fadvise.2:90 build/C/man3/posix_fallocate.3:72 build/C/man3/posix_memalign.3:157 build/C/man2/readahead.2:72 build/C/man2/remap_file_pages.2:139 build/C/man3/shm_open.3:180 build/C/man2/shmctl.2:305 build/C/man2/shmget.2:188 build/C/man2/shmop.2:182 build/C/man2/subpage_prot.2:71 build/C/man2/sync_file_range.2:147 build/C/man2/memfd_create.2:133 build/C/man2/s390_pci_mmio_write.2:77
#, no-wrap
msgid "ERRORS"
msgstr ""
#. type: TP
-#: build/C/man2/alloc_hugepages.2:119 build/C/man2/fallocate.2:151
+#: build/C/man2/alloc_hugepages.2:119 build/C/man2/fallocate.2:319
#, no-wrap
msgid "B<ENOSYS>"
msgstr ""
msgstr ""
#. type: SH
-#: build/C/man2/alloc_hugepages.2:130 build/C/man3/alloca.3:63 build/C/man2/cacheflush.2:74 build/C/man2/fallocate.2:186 build/C/man2/madvise.2:307 build/C/man3/malloc_hook.3:76 build/C/man3/mallopt.3:390 build/C/man2/mlock.2:187 build/C/man2/mmap.2:483 build/C/man2/mmap2.2:77 build/C/man2/mprotect.2:107 build/C/man2/mremap.2:186 build/C/man2/msync.2:96 build/C/man3/mtrace.3:76 build/C/man2/posix_fadvise.2:111 build/C/man3/posix_fallocate.3:101 build/C/man3/posix_memalign.3:180 build/C/man2/readahead.2:87 build/C/man2/remap_file_pages.2:151 build/C/man3/shm_open.3:249 build/C/man7/shm_overview.7:101 build/C/man2/shmctl.2:366 build/C/man2/shmget.2:229 build/C/man2/shmop.2:226 build/C/man2/subpage_prot.2:91 build/C/man2/sync_file_range.2:180
+#: build/C/man2/alloc_hugepages.2:130 build/C/man3/alloca.3:70 build/C/man2/cacheflush.2:75 build/C/man2/fallocate.2:375 build/C/man2/madvise.2:332 build/C/man3/mallinfo.3:110 build/C/man3/malloc_get_state.3:86 build/C/man3/malloc_hook.3:80 build/C/man3/malloc_info.3:63 build/C/man3/malloc_stats.3:55 build/C/man3/malloc_trim.3:60 build/C/man3/malloc_usable_size.3:53 build/C/man3/mallopt.3:392 build/C/man3/mcheck.3:145 build/C/man2/mlock.2:186 build/C/man2/mmap.2:499 build/C/man2/mmap2.2:77 build/C/man2/mprotect.2:112 build/C/man2/mremap.2:185 build/C/man2/msync.2:96 build/C/man3/mtrace.3:78 build/C/man2/posix_fadvise.2:122 build/C/man3/posix_fallocate.3:108 build/C/man3/posix_memalign.3:182 build/C/man2/readahead.2:88 build/C/man2/remap_file_pages.2:161 build/C/man3/shm_open.3:251 build/C/man7/shm_overview.7:101 build/C/man2/shmctl.2:377 build/C/man2/shmget.2:248 build/C/man2/shmop.2:228 build/C/man2/subpage_prot.2:96 build/C/man2/sync_file_range.2:180 build/C/man2/memfd_create.2:161 build/C/man2/s390_pci_mmio_write.2:100
#, no-wrap
msgid "CONFORMING TO"
msgstr ""
msgstr ""
#. type: SH
-#: build/C/man2/alloc_hugepages.2:133 build/C/man3/alloca.3:71 build/C/man2/madvise.2:328 build/C/man3/malloc_hook.3:78 build/C/man2/mlock.2:214 build/C/man2/mmap.2:501 build/C/man2/mmap2.2:79 build/C/man2/mprotect.2:116 build/C/man2/mremap.2:192 build/C/man3/mtrace.3:78 build/C/man2/posix_fadvise.2:120 build/C/man3/posix_memalign.3:219 build/C/man3/shm_open.3:255 build/C/man7/shm_overview.7:103 build/C/man2/shmctl.2:371 build/C/man2/shmget.2:235 build/C/man2/shmop.2:245 build/C/man2/subpage_prot.2:93 build/C/man2/sync_file_range.2:183
+#: build/C/man2/alloc_hugepages.2:133 build/C/man3/alloca.3:78 build/C/man2/madvise.2:354 build/C/man3/malloc_get_state.3:88 build/C/man3/malloc_hook.3:82 build/C/man3/malloc_info.3:65 build/C/man3/malloc_stats.3:57 build/C/man3/malloc_trim.3:62 build/C/man3/malloc_usable_size.3:55 build/C/man3/mcheck.3:147 build/C/man2/mlock.2:213 build/C/man2/mmap.2:517 build/C/man2/mmap2.2:79 build/C/man2/mprotect.2:121 build/C/man2/mremap.2:191 build/C/man2/msync.2:120 build/C/man3/mtrace.3:80 build/C/man2/posix_fadvise.2:131 build/C/man3/posix_fallocate.3:133 build/C/man3/posix_memalign.3:221 build/C/man2/readahead.2:93 build/C/man2/remap_file_pages.2:165 build/C/man3/shm_open.3:257 build/C/man7/shm_overview.7:103 build/C/man2/shmctl.2:382 build/C/man2/shmget.2:256 build/C/man2/shmop.2:243 build/C/man2/subpage_prot.2:98 build/C/man2/sync_file_range.2:183 build/C/man2/memfd_create.2:165 build/C/man2/s390_pci_mmio_write.2:103
#, no-wrap
msgid "NOTES"
msgstr ""
#: build/C/man2/alloc_hugepages.2:141
msgid ""
"These system calls are gone; they existed only in Linux 2.5.36 through to "
-"2.5.54. Now the hugetlbfs file system can be used instead. Memory backed "
-"by huge pages (if the CPU supports them) is obtained by using B<mmap>(2) to "
-"map files in this virtual file system."
+"2.5.54. Now the hugetlbfs filesystem can be used instead. Memory backed by "
+"huge pages (if the CPU supports them) is obtained by using B<mmap>(2) to "
+"map files in this virtual filesystem."
msgstr ""
#. type: Plain text
"boot parameter."
msgstr ""
+#. type: SH
+#: build/C/man2/alloc_hugepages.2:150 build/C/man3/alloca.3:162 build/C/man2/cacheflush.2:89 build/C/man2/fallocate.2:383 build/C/man2/madvise.2:388 build/C/man3/mallinfo.3:279 build/C/man3/malloc_get_state.3:114 build/C/man3/malloc_hook.3:142 build/C/man3/malloc_info.3:262 build/C/man3/malloc_stats.3:67 build/C/man3/malloc_trim.3:82 build/C/man3/malloc_usable_size.3:69 build/C/man3/mallopt.3:568 build/C/man3/mcheck.3:208 build/C/man2/mlock.2:343 build/C/man2/mmap.2:741 build/C/man2/mmap2.2:101 build/C/man2/mprotect.2:228 build/C/man2/mremap.2:214 build/C/man2/msync.2:151 build/C/man3/mtrace.3:172 build/C/man2/posix_fadvise.2:215 build/C/man3/posix_fallocate.3:143 build/C/man3/posix_memalign.3:277 build/C/man2/readahead.2:113 build/C/man2/remap_file_pages.2:183 build/C/man3/shm_open.3:283 build/C/man7/shm_overview.7:127 build/C/man2/shmctl.2:435 build/C/man2/shmget.2:391 build/C/man2/shmop.2:301 build/C/man2/subpage_prot.2:134 build/C/man2/sync_file_range.2:227 build/C/man2/memfd_create.2:493 build/C/man2/s390_pci_mmio_write.2:109
+#, no-wrap
+msgid "COLOPHON"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/alloc_hugepages.2:158 build/C/man3/alloca.3:170 build/C/man2/cacheflush.2:97 build/C/man2/fallocate.2:391 build/C/man2/madvise.2:396 build/C/man3/mallinfo.3:287 build/C/man3/malloc_get_state.3:122 build/C/man3/malloc_hook.3:150 build/C/man3/malloc_info.3:270 build/C/man3/malloc_stats.3:75 build/C/man3/malloc_trim.3:90 build/C/man3/malloc_usable_size.3:77 build/C/man3/mallopt.3:576 build/C/man3/mcheck.3:216 build/C/man2/mlock.2:351 build/C/man2/mmap.2:749 build/C/man2/mmap2.2:109 build/C/man2/mprotect.2:236 build/C/man2/mremap.2:222 build/C/man2/msync.2:159 build/C/man3/mtrace.3:180 build/C/man2/posix_fadvise.2:223 build/C/man3/posix_fallocate.3:151 build/C/man3/posix_memalign.3:285 build/C/man2/readahead.2:121 build/C/man2/remap_file_pages.2:191 build/C/man3/shm_open.3:291 build/C/man7/shm_overview.7:135 build/C/man2/shmctl.2:443 build/C/man2/shmget.2:399 build/C/man2/shmop.2:309 build/C/man2/subpage_prot.2:142 build/C/man2/sync_file_range.2:235 build/C/man2/memfd_create.2:501 build/C/man2/s390_pci_mmio_write.2:117
+msgid ""
+"This page is part of release 3.79 of the Linux I<man-pages> project. A "
+"description of the project, information about reporting bugs, and the latest "
+"version of this page, can be found at "
+"\\%http://www.kernel.org/doc/man-pages/."
+msgstr ""
+
#. type: TH
-#: build/C/man3/alloca.3:41
+#: build/C/man3/alloca.3:43
#, no-wrap
msgid "ALLOCA"
msgstr ""
#. type: TH
-#: build/C/man3/alloca.3:41
+#: build/C/man3/alloca.3:43
#, no-wrap
-msgid "2008-01-24"
+msgid "2013-10-07"
msgstr ""
#. type: TH
-#: build/C/man3/alloca.3:41 build/C/man3/malloc_hook.3:6 build/C/man3/mtrace.3:23 build/C/man3/posix_fallocate.3:23 build/C/man3/posix_memalign.3:28
+#: build/C/man3/alloca.3:43 build/C/man3/malloc_get_state.3:25 build/C/man3/malloc_hook.3:10 build/C/man3/malloc_info.3:25 build/C/man3/malloc_usable_size.3:25 build/C/man3/mcheck.3:25 build/C/man3/mtrace.3:25 build/C/man3/posix_fallocate.3:25 build/C/man3/posix_memalign.3:29
#, no-wrap
msgid "GNU"
msgstr ""
#. type: Plain text
-#: build/C/man3/alloca.3:44
+#: build/C/man3/alloca.3:46
msgid "alloca - allocate memory that is automatically freed"
msgstr ""
#. type: Plain text
-#: build/C/man3/alloca.3:46
+#: build/C/man3/alloca.3:48
msgid "B<#include E<lt>alloca.hE<gt>>"
msgstr ""
#. type: Plain text
-#: build/C/man3/alloca.3:48
+#: build/C/man3/alloca.3:50
msgid "B<void *alloca(size_t >I<size>B<);>"
msgstr ""
#. type: Plain text
-#: build/C/man3/alloca.3:58
+#: build/C/man3/alloca.3:60
msgid ""
"The B<alloca>() function allocates I<size> bytes of space in the stack "
"frame of the caller. This temporary space is automatically freed when the "
msgstr ""
#. type: Plain text
-#: build/C/man3/alloca.3:63
+#: build/C/man3/alloca.3:65
msgid ""
"The B<alloca>() function returns a pointer to the beginning of the "
"allocated space. If the allocation causes stack overflow, program behavior "
"is undefined."
msgstr ""
+#. type: SH
+#: build/C/man3/alloca.3:65 build/C/man3/malloc_usable_size.3:48 build/C/man3/posix_fallocate.3:103
+#, no-wrap
+msgid "ATTRIBUTES"
+msgstr ""
+
+#. type: SS
+#: build/C/man3/alloca.3:66 build/C/man3/malloc_usable_size.3:49 build/C/man3/posix_fallocate.3:104
+#, no-wrap
+msgid "Multithreading (see pthreads(7))"
+msgstr ""
+
#. type: Plain text
-#: build/C/man3/alloca.3:65
+#: build/C/man3/alloca.3:70
+msgid "The B<alloca>() function is thread-safe."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/alloca.3:72
msgid "This function is not in POSIX.1-2001."
msgstr ""
#. type: Plain text
-#: build/C/man3/alloca.3:71
+#: build/C/man3/alloca.3:78
msgid ""
"There is evidence that the B<alloca>() function appeared in 32V, PWB, "
"PWB.2, 3BSD, and 4BSD. There is a man page for it in 4.3BSD. Linux uses "
msgstr ""
#. type: Plain text
-#: build/C/man3/alloca.3:86
+#: build/C/man3/alloca.3:93
msgid ""
"The B<alloca>() function is machine- and compiler-dependent. For certain "
"applications, its use can improve efficiency compared to the use of "
msgstr ""
#. type: Plain text
-#: build/C/man3/alloca.3:95
+#: build/C/man3/alloca.3:102
msgid ""
"Because the space allocated by B<alloca>() is allocated within the stack "
"frame, that space is automatically freed if the function return is jumped "
msgstr ""
#. type: Plain text
-#: build/C/man3/alloca.3:100
+#: build/C/man3/alloca.3:107
msgid "Do not attempt to B<free>(3) space allocated by B<alloca>()!"
msgstr ""
#. type: SS
-#: build/C/man3/alloca.3:100
+#: build/C/man3/alloca.3:107
#, no-wrap
-msgid "Notes on the GNU Version"
+msgid "Notes on the GNU version"
msgstr ""
#. type: Plain text
-#: build/C/man3/alloca.3:122
+#: build/C/man3/alloca.3:129
msgid ""
"Normally, B<gcc>(1) translates calls to B<alloca>() with inlined code. "
"This is not done when either the I<-ansi>, I<-std=c89>, I<-std=c99>, or the "
-"I<-fno-builtin> option is given (and the header I<E<lt>alloca.hE<gt>> is not "
-"included). But beware! By default the glibc version of "
-"I<E<lt>stdlib.hE<gt>> includes I<E<lt>alloca.hE<gt>> and that contains the "
-"line:"
+"I<-std=c11> option is given B<and> the header I<E<lt>alloca.hE<gt>> is not "
+"included. Otherwise, (without an -ansi or -std=c* option) the glibc version "
+"of I<E<lt>stdlib.hE<gt>> includes I<E<lt>alloca.hE<gt>> and that contains "
+"the lines:"
msgstr ""
#. type: Plain text
-#: build/C/man3/alloca.3:125
+#: build/C/man3/alloca.3:134
#, no-wrap
-msgid " #define alloca(size) __builtin_alloca (size)\n"
+msgid ""
+" #ifdef __GNUC__\n"
+" #define alloca(size) __builtin_alloca (size)\n"
+" #endif\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/alloca.3:128
+#: build/C/man3/alloca.3:137
msgid "with messy consequences if one has a private version of this function."
msgstr ""
#. type: Plain text
-#: build/C/man3/alloca.3:132
+#: build/C/man3/alloca.3:141
msgid ""
"The fact that the code is inlined means that it is impossible to take the "
"address of this function, or to change its behavior by linking with a "
msgstr ""
#. type: Plain text
-#: build/C/man3/alloca.3:136
+#: build/C/man3/alloca.3:145
msgid ""
"The inlined code often consists of a single instruction adjusting the stack "
"pointer, and does not check for stack overflow. Thus, there is no NULL "
msgstr ""
#. type: SH
-#: build/C/man3/alloca.3:136 build/C/man2/cacheflush.2:81 build/C/man3/mallopt.3:404 build/C/man2/mlock.2:305 build/C/man2/mmap.2:544 build/C/man3/mtrace.3:100 build/C/man2/posix_fadvise.2:177 build/C/man2/shmget.2:284
+#: build/C/man3/alloca.3:145 build/C/man2/cacheflush.2:82 build/C/man3/mallinfo.3:114 build/C/man3/mallopt.3:406 build/C/man2/mlock.2:311 build/C/man2/mmap.2:590 build/C/man3/mtrace.3:102 build/C/man2/posix_fadvise.2:204 build/C/man2/readahead.2:98 build/C/man2/shmget.2:376
#, no-wrap
msgid "BUGS"
msgstr ""
#. type: Plain text
-#: build/C/man3/alloca.3:141
+#: build/C/man3/alloca.3:150
msgid ""
"There is no error indication if the stack frame cannot be extended. "
"(However, after a failed allocation, the program is likely to receive a "
msgstr ""
#. type: Plain text
-#: build/C/man3/alloca.3:149
+#: build/C/man3/alloca.3:158
msgid ""
"On many systems B<alloca>() cannot be used inside the list of arguments of "
"a function call, because the stack space reserved by B<alloca>() would "
msgstr ""
#. type: SH
-#: build/C/man3/alloca.3:149 build/C/man2/fallocate.2:189 build/C/man2/madvise.2:353 build/C/man3/malloc_hook.3:133 build/C/man3/mallopt.3:568 build/C/man2/mlock.2:330 build/C/man2/mmap.2:653 build/C/man2/mmap2.2:92 build/C/man2/mprotect.2:220 build/C/man2/mremap.2:200 build/C/man2/msync.2:118 build/C/man3/mtrace.3:165 build/C/man2/posix_fadvise.2:182 build/C/man3/posix_fallocate.3:126 build/C/man3/posix_memalign.3:270 build/C/man2/readahead.2:92 build/C/man2/remap_file_pages.2:155 build/C/man3/shm_open.3:269 build/C/man7/shm_overview.7:114 build/C/man2/shmctl.2:403 build/C/man2/shmget.2:290 build/C/man2/shmop.2:282 build/C/man2/subpage_prot.2:120 build/C/man2/sync_file_range.2:217
+#: build/C/man3/alloca.3:158 build/C/man2/fallocate.2:378 build/C/man2/madvise.2:379 build/C/man3/mallinfo.3:270 build/C/man3/malloc_get_state.3:111 build/C/man3/malloc_hook.3:137 build/C/man3/malloc_info.3:256 build/C/man3/malloc_stats.3:61 build/C/man3/malloc_trim.3:78 build/C/man3/malloc_usable_size.3:67 build/C/man3/mallopt.3:554 build/C/man3/mcheck.3:204 build/C/man2/mlock.2:336 build/C/man2/mmap.2:715 build/C/man2/mmap2.2:95 build/C/man2/mprotect.2:225 build/C/man2/mremap.2:199 build/C/man2/msync.2:147 build/C/man3/mtrace.3:167 build/C/man2/posix_fadvise.2:209 build/C/man3/posix_fallocate.3:138 build/C/man3/posix_memalign.3:272 build/C/man2/readahead.2:107 build/C/man2/remap_file_pages.2:176 build/C/man3/shm_open.3:271 build/C/man7/shm_overview.7:114 build/C/man2/shmctl.2:428 build/C/man2/shmget.2:382 build/C/man2/shmop.2:293 build/C/man2/subpage_prot.2:128 build/C/man2/sync_file_range.2:222 build/C/man2/memfd_create.2:487 build/C/man2/s390_pci_mmio_write.2:107
#, no-wrap
msgid "SEE ALSO"
msgstr ""
#. type: Plain text
-#: build/C/man3/alloca.3:152
+#: build/C/man3/alloca.3:162
msgid "B<brk>(2), B<longjmp>(3), B<malloc>(3)"
msgstr ""
#. type: TH
-#: build/C/man2/cacheflush.2:24
+#: build/C/man2/cacheflush.2:25
#, no-wrap
msgid "CACHEFLUSH"
msgstr ""
#. type: TH
-#: build/C/man2/cacheflush.2:24
+#: build/C/man2/cacheflush.2:25
#, no-wrap
msgid "2007-05-26"
msgstr ""
#. type: Plain text
-#: build/C/man2/cacheflush.2:27
+#: build/C/man2/cacheflush.2:28
msgid "cacheflush - flush contents of instruction and/or data cache"
msgstr ""
#. type: Plain text
-#: build/C/man2/cacheflush.2:30
+#: build/C/man2/cacheflush.2:31
#, no-wrap
msgid "B<#include E<lt>asm/cachectl.hE<gt>>\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/cacheflush.2:32
+#: build/C/man2/cacheflush.2:33
#, no-wrap
msgid "B<int cacheflush(char *>I<addr>B<, int >I<nbytes>B<, int >I<cache>B<);>\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/cacheflush.2:42
+#: build/C/man2/cacheflush.2:43
msgid ""
"B<cacheflush>() flushes the contents of the indicated cache(s) for the user "
"addresses in the range I<addr> to I<(addr+nbytes-1)>. I<cache> may be one "
msgstr ""
#. type: TP
-#: build/C/man2/cacheflush.2:42
+#: build/C/man2/cacheflush.2:43
#, no-wrap
msgid "B<ICACHE>"
msgstr ""
#. type: Plain text
-#: build/C/man2/cacheflush.2:45
+#: build/C/man2/cacheflush.2:46
msgid "Flush the instruction cache."
msgstr ""
#. type: TP
-#: build/C/man2/cacheflush.2:45
+#: build/C/man2/cacheflush.2:46
#, no-wrap
msgid "B<DCACHE>"
msgstr ""
#. type: Plain text
-#: build/C/man2/cacheflush.2:48
+#: build/C/man2/cacheflush.2:49
msgid "Write back to memory and invalidate the affected valid cache lines."
msgstr ""
#. type: TP
-#: build/C/man2/cacheflush.2:48
+#: build/C/man2/cacheflush.2:49
#, no-wrap
msgid "B<BCACHE>"
msgstr ""
#. type: Plain text
-#: build/C/man2/cacheflush.2:52
+#: build/C/man2/cacheflush.2:53
msgid "Same as B<(ICACHE|DCACHE)>."
msgstr ""
#. type: Plain text
-#: build/C/man2/cacheflush.2:58
+#: build/C/man2/cacheflush.2:59
msgid ""
"B<cacheflush>() returns 0 on success or -1 on error. If errors are "
"detected, I<errno> will indicate the error."
msgstr ""
#. type: TP
-#: build/C/man2/cacheflush.2:59 build/C/man2/mmap2.2:62 build/C/man2/mremap.2:143 build/C/man2/shmctl.2:303 build/C/man2/subpage_prot.2:67
+#: build/C/man2/cacheflush.2:60 build/C/man2/mmap2.2:62 build/C/man2/mremap.2:142 build/C/man2/shmctl.2:314 build/C/man2/subpage_prot.2:72 build/C/man2/memfd_create.2:134 build/C/man2/s390_pci_mmio_write.2:78 build/C/man2/s390_pci_mmio_write.2:83
#, no-wrap
msgid "B<EFAULT>"
msgstr ""
#. type: Plain text
-#: build/C/man2/cacheflush.2:66
+#: build/C/man2/cacheflush.2:67
msgid ""
"Some or all of the address range I<addr> to I<(addr+nbytes-1)> is not "
"accessible."
msgstr ""
#. type: TP
-#: build/C/man2/cacheflush.2:66 build/C/man2/fallocate.2:124 build/C/man2/madvise.2:264 build/C/man2/mlock.2:158 build/C/man2/mlock.2:165 build/C/man2/mlock.2:177 build/C/man2/mmap.2:421 build/C/man2/mmap.2:429 build/C/man2/mmap.2:434 build/C/man2/mmap2.2:65 build/C/man2/mprotect.2:89 build/C/man2/mremap.2:152 build/C/man2/msync.2:80 build/C/man2/posix_fadvise.2:93 build/C/man3/posix_fallocate.3:79 build/C/man3/posix_memalign.3:156 build/C/man2/readahead.2:76 build/C/man2/remap_file_pages.2:130 build/C/man2/remap_file_pages.2:137 build/C/man3/shm_open.3:211 build/C/man2/shmctl.2:317 build/C/man2/shmget.2:196 build/C/man2/shmop.2:195 build/C/man2/shmop.2:218 build/C/man2/subpage_prot.2:72 build/C/man2/sync_file_range.2:152
+#: build/C/man2/cacheflush.2:67 build/C/man2/fallocate.2:247 build/C/man2/fallocate.2:259 build/C/man2/fallocate.2:269 build/C/man2/fallocate.2:279 build/C/man2/fallocate.2:287 build/C/man2/madvise.2:282 build/C/man3/malloc_info.3:56 build/C/man2/mlock.2:157 build/C/man2/mlock.2:164 build/C/man2/mlock.2:176 build/C/man2/mmap.2:421 build/C/man2/mmap.2:429 build/C/man2/mmap.2:434 build/C/man2/mmap2.2:65 build/C/man2/mprotect.2:94 build/C/man2/mremap.2:151 build/C/man2/msync.2:80 build/C/man2/posix_fadvise.2:94 build/C/man3/posix_fallocate.3:81 build/C/man3/posix_memalign.3:158 build/C/man2/readahead.2:77 build/C/man2/remap_file_pages.2:140 build/C/man2/remap_file_pages.2:147 build/C/man3/shm_open.3:213 build/C/man2/shmctl.2:328 build/C/man2/shmget.2:207 build/C/man2/shmget.2:215 build/C/man2/shmop.2:197 build/C/man2/shmop.2:220 build/C/man2/subpage_prot.2:77 build/C/man2/sync_file_range.2:152 build/C/man2/memfd_create.2:139 build/C/man2/s390_pci_mmio_write.2:87
#, no-wrap
msgid "B<EINVAL>"
msgstr ""
#. type: Plain text
-#: build/C/man2/cacheflush.2:74
+#: build/C/man2/cacheflush.2:75
msgid "I<cache> is not one of B<ICACHE>, B<DCACHE>, or B<BCACHE>."
msgstr ""
-#. FIXME This system call was only on MIPS back in 1.2 days, but
-#. by now it is on a number of other architectures (but not i386).
+#. FIXME The cacheflush() system call was only on MIPS back in 1.2 days,
+#. but by now it is on a number of other architectures (but not i386).
#. Investigate the details and update this page.
#. Irix 6.5 appears to have a cacheflush() syscall -- mtk
#. type: Plain text
-#: build/C/man2/cacheflush.2:81
+#: build/C/man2/cacheflush.2:82
msgid ""
-"This Linux-specific system call is only available on MIPS-based systems. It "
+"This Linux-specific system call is available only on MIPS-based systems. It "
"should not be used in programs intended to be portable."
msgstr ""
#. type: Plain text
-#: build/C/man2/cacheflush.2:87
+#: build/C/man2/cacheflush.2:89
msgid ""
"The current implementation ignores the I<addr> and I<nbytes> arguments. "
"Therefore, the whole cache is always flushed."
msgstr ""
#. type: TH
-#: build/C/man2/fallocate.2:8
+#: build/C/man2/fallocate.2:11
#, no-wrap
msgid "FALLOCATE"
msgstr ""
#. type: TH
-#: build/C/man2/fallocate.2:8
+#: build/C/man2/fallocate.2:11 build/C/man3/malloc_info.3:25 build/C/man2/mmap.2:40 build/C/man3/posix_fallocate.3:25 build/C/man3/shm_open.3:26 build/C/man2/memfd_create.2:21
#, no-wrap
-msgid "2012-02-27"
+msgid "2015-01-22"
msgstr ""
#. type: Plain text
-#: build/C/man2/fallocate.2:11
+#: build/C/man2/fallocate.2:14
msgid "fallocate - manipulate file space"
msgstr ""
#. type: Plain text
-#: build/C/man2/fallocate.2:15 build/C/man2/readahead.2:35
+#: build/C/man2/fallocate.2:18 build/C/man2/readahead.2:35
#, no-wrap
msgid ""
"B<#define _GNU_SOURCE> /* See feature_test_macros(7) */\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/fallocate.2:18
+#: build/C/man2/fallocate.2:21
#, no-wrap
msgid ""
"B<int fallocate(int >I<fd>B<, int >I<mode>B<, off_t >I<offset>B<, off_t "
msgstr ""
#. type: Plain text
-#: build/C/man2/fallocate.2:24
+#: build/C/man2/fallocate.2:27
msgid ""
"This is a nonportable, Linux-specific system call. For the portable, "
"POSIX.1-specified method of ensuring that space is allocated for a file, see "
msgstr ""
#. type: Plain text
-#: build/C/man2/fallocate.2:34
+#: build/C/man2/fallocate.2:37
msgid ""
"B<fallocate>() allows the caller to directly manipulate the allocated disk "
"space for the file referred to by I<fd> for the byte range starting at "
msgstr ""
#. type: Plain text
-#: build/C/man2/fallocate.2:39
+#: build/C/man2/fallocate.2:42
msgid ""
"The I<mode> argument determines the operation to be performed on the given "
"range. Details of the supported operations are given in the subsections "
msgstr ""
#. type: SS
-#: build/C/man2/fallocate.2:39
+#: build/C/man2/fallocate.2:42
#, no-wrap
msgid "Allocating disk space"
msgstr ""
#. type: Plain text
-#: build/C/man2/fallocate.2:58
+#: build/C/man2/fallocate.2:65
msgid ""
"The default operation (i.e., I<mode> is zero) of B<fallocate>() allocates "
-"and initializes to zero the disk space within the range specified by "
-"I<offset> and I<len>. The file size (as reported by B<stat>(2)) will be "
-"changed if I<offset>+I<len> is greater than the file size. This default "
-"behavior closely resembles the behavior of the B<posix_fallocate>(3) "
-"library function, and is intended as a method of optimally implementing that "
-"function."
+"the disk space within the range specified by I<offset> and I<len>. The file "
+"size (as reported by B<stat>(2)) will be changed if I<offset>+I<len> is "
+"greater than the file size. Any subregion within the range specified by "
+"I<offset> and I<len> that did not contain data before the call will be "
+"initialized to zero. This default behavior closely resembles the behavior "
+"of the B<posix_fallocate>(3) library function, and is intended as a method "
+"of optimally implementing that function."
msgstr ""
#. type: Plain text
-#: build/C/man2/fallocate.2:64
+#: build/C/man2/fallocate.2:71
msgid ""
"After a successful call, subsequent writes into the range specified by "
"I<offset> and I<len> are guaranteed not to fail because of lack of disk "
msgstr ""
#. type: Plain text
-#: build/C/man2/fallocate.2:75
+#: build/C/man2/fallocate.2:82
msgid ""
"If the B<FALLOC_FL_KEEP_SIZE> flag is specified in I<mode>, the behavior of "
"the call is similar, but the file size will not be changed even if "
msgstr ""
#. type: Plain text
-#: build/C/man2/fallocate.2:79
+#: build/C/man2/fallocate.2:86
msgid ""
"Because allocation is done in block size chunks, B<fallocate>() may "
"allocate a larger range of disk space than was specified."
msgstr ""
#. type: SS
-#: build/C/man2/fallocate.2:79
+#: build/C/man2/fallocate.2:86
#, no-wrap
msgid "Deallocating file space"
msgstr ""
#. type: Plain text
-#: build/C/man2/fallocate.2:94
+#: build/C/man2/fallocate.2:101
msgid ""
"Specifying the B<FALLOC_FL_PUNCH_HOLE> flag (available since Linux 2.6.38) "
"in I<mode> deallocates space (i.e., creates a hole) in the byte range "
"starting at I<offset> and continuing for I<len> bytes. Within the specified "
-"range, partial file system blocks are zeroed, and whole file system blocks "
-"are removed from the file. After a successful call, subsequent reads from "
-"this range will return zeroes."
+"range, partial filesystem blocks are zeroed, and whole filesystem blocks are "
+"removed from the file. After a successful call, subsequent reads from this "
+"range will return zeroes."
msgstr ""
#. type: Plain text
-#: build/C/man2/fallocate.2:105
+#: build/C/man2/fallocate.2:112
msgid ""
"The B<FALLOC_FL_PUNCH_HOLE> flag must be ORed with B<FALLOC_FL_KEEP_SIZE> in "
"I<mode>; in other words, even when punching off the end of the file, the "
msgstr ""
#. type: Plain text
-#: build/C/man2/fallocate.2:109
+#: build/C/man2/fallocate.2:117
+msgid ""
+"Not all filesystems support B<FALLOC_FL_PUNCH_HOLE>; if a filesystem doesn't "
+"support the operation, an error is returned. The operation is supported on "
+"at least the following filesystems:"
+msgstr ""
+
+#. type: IP
+#: build/C/man2/fallocate.2:117 build/C/man2/fallocate.2:119 build/C/man2/fallocate.2:122 build/C/man2/fallocate.2:124 build/C/man2/fallocate.2:222 build/C/man2/fallocate.2:225 build/C/man2/madvise.2:286 build/C/man2/madvise.2:292 build/C/man2/madvise.2:295 build/C/man2/madvise.2:298 build/C/man2/madvise.2:301 build/C/man3/mallopt.3:235 build/C/man3/mallopt.3:241 build/C/man2/shmop.2:62 build/C/man2/shmop.2:68 build/C/man2/shmop.2:80 build/C/man2/memfd_create.2:248 build/C/man2/memfd_create.2:258 build/C/man2/memfd_create.2:266
+#, no-wrap
+msgid "*"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/fallocate.2:119
+msgid "XFS (since Linux 2.6.38)"
+msgstr ""
+
+#. commit a4bb6b64e39abc0e41ca077725f2a72c868e7622
+#. type: Plain text
+#: build/C/man2/fallocate.2:122
+msgid "ext4 (since Linux 3.0)"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/fallocate.2:124
+msgid "Btrfs (since Linux 3.7)"
+msgstr ""
+
+#. commit 83e4fa9c16e4af7122e31be3eca5d57881d236fe
+#. type: Plain text
+#: build/C/man2/fallocate.2:127
+msgid "tmpfs (since Linux 3.5)"
+msgstr ""
+
+#. type: SS
+#: build/C/man2/fallocate.2:127
+#, no-wrap
+msgid "Collapsing file space"
+msgstr ""
+
+#. commit 00f5e61998dd17f5375d9dfc01331f104b83f841
+#. type: Plain text
+#: build/C/man2/fallocate.2:147
msgid ""
-"Not all file systems support B<FALLOC_FL_PUNCH_HOLE>; if a file system "
-"doesn't support the operation, an error is returned."
+"Specifying the B<FALLOC_FL_COLLAPSE_RANGE> flag (available since Linux 3.15) "
+"in I<mode> removes a byte range from a file, without leaving a hole. The "
+"byte range to be collapsed starts at I<offset> and continues for I<len> "
+"bytes. At the completion of the operation, the contents of the file "
+"starting at the location I<offset+len> will be appended at the location "
+"I<offset>, and the file will be I<len> bytes smaller."
msgstr ""
#. type: Plain text
-#: build/C/man2/fallocate.2:112
-msgid "B<fallocate>() returns zero on success, and -1 on failure."
+#: build/C/man2/fallocate.2:161
+msgid ""
+"A filesystem may place limitations on the granularity of the operation, in "
+"order to ensure efficient implementation. Typically, I<offset> and I<len> "
+"must be a multiple of the filesystem logical block size, which varies "
+"according to the filesystem type and configuration. If a filesystem has "
+"such a requirement, B<fallocate>() will fail with the error B<EINVAL> if "
+"this requirement is violated."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/fallocate.2:170
+msgid ""
+"If the region specified by I<offset> plus I<len> reaches or passes the end "
+"of file, an error is returned; instead, use B<ftruncate>(2) to truncate a "
+"file."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/fallocate.2:175
+msgid ""
+"No other flags may be specified in I<mode> in conjunction with "
+"B<FALLOC_FL_COLLAPSE_RANGE>."
+msgstr ""
+
+#. commit 9eb79482a97152930b113b51dff530aba9e28c8e
+#. commit e1d8fb88a64c1f8094b9f6c3b6d2d9e6719c970d
+#. type: Plain text
+#: build/C/man2/fallocate.2:183
+msgid ""
+"As at Linux 3.15, B<FALLOC_FL_COLLAPSE_RANGE> is supported by ext4 (only for "
+"extent-based files) and XFS."
+msgstr ""
+
+#. type: SS
+#: build/C/man2/fallocate.2:183
+#, no-wrap
+msgid "Zeroing file space"
+msgstr ""
+
+#. commit 409332b65d3ed8cfa7a8030f1e9d52f372219642
+#. type: Plain text
+#: build/C/man2/fallocate.2:199
+msgid ""
+"Specifying the B<FALLOC_FL_ZERO_RANGE> flag (available since Linux 3.14) in "
+"I<mode> zeroes space in the byte range starting at I<offset> and continuing "
+"for I<len> bytes. Within the specified range, blocks are preallocated for "
+"the regions that span the holes in the file. After a successful call, "
+"subsequent reads from this range will return zeroes."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/fallocate.2:205
+msgid ""
+"Zeroing is done within the filesystem preferably by converting the range "
+"into unwritten extents. This approach means that the specified range will "
+"not be physically zeroed out on the device (except for partial blocks at the "
+"either end of the range), and I/O is (otherwise) required only to update "
+"metadata."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/fallocate.2:217
+msgid ""
+"If the B<FALLOC_FL_KEEP_SIZE> flag is additionally specified in I<mode>, the "
+"behavior of the call is similar, but the file size will not be changed even "
+"if I<offset>+I<len> is greater than the file size. This behavior is the "
+"same as when preallocating space with B<FALLOC_FL_KEEP_SIZE> specified."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/fallocate.2:222
+msgid ""
+"Not all filesystems support B<FALLOC_FL_ZERO_RANGE>; if a filesystem doesn't "
+"support the operation, an error is returned. The operation is supported on "
+"at least the following filesystems:"
+msgstr ""
+
+#. commit 376ba313147b4172f3e8cf620b9fb591f3e8cdfa
+#. type: Plain text
+#: build/C/man2/fallocate.2:225
+msgid "XFS (since Linux 3.14)"
+msgstr ""
+
+#. commit b8a8684502a0fc852afa0056c6bb2a9273f6fcc0
+#. type: Plain text
+#: build/C/man2/fallocate.2:228
+msgid "ext4, for extent-based files (since Linux 3.14)"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/fallocate.2:235
+msgid ""
+"On success, B<fallocate>() returns zero. On error, -1 is returned and "
+"I<errno> is set to indicate the error."
msgstr ""
#. type: TP
-#: build/C/man2/fallocate.2:113 build/C/man2/madvise.2:261 build/C/man2/mmap.2:415 build/C/man2/posix_fadvise.2:90 build/C/man3/posix_fallocate.3:71 build/C/man2/readahead.2:72 build/C/man2/sync_file_range.2:148
+#: build/C/man2/fallocate.2:236 build/C/man2/madvise.2:279 build/C/man2/mmap.2:415 build/C/man2/posix_fadvise.2:91 build/C/man3/posix_fallocate.3:73 build/C/man2/readahead.2:73 build/C/man2/sync_file_range.2:148
#, no-wrap
msgid "B<EBADF>"
msgstr ""
#. type: Plain text
-#: build/C/man2/fallocate.2:117 build/C/man3/posix_fallocate.3:75
+#: build/C/man2/fallocate.2:240 build/C/man3/posix_fallocate.3:77
msgid "I<fd> is not a valid file descriptor, or is not opened for writing."
msgstr ""
#. type: TP
-#: build/C/man2/fallocate.2:117 build/C/man3/posix_fallocate.3:75
+#: build/C/man2/fallocate.2:240 build/C/man3/posix_fallocate.3:77
#, no-wrap
msgid "B<EFBIG>"
msgstr ""
#. type: Plain text
-#: build/C/man2/fallocate.2:121
+#: build/C/man2/fallocate.2:244
msgid "I<offset>+I<len> exceeds the maximum file size."
msgstr ""
#. type: TP
-#: build/C/man2/fallocate.2:121
+#: build/C/man2/fallocate.2:244
#, no-wrap
msgid "B<EINTR>"
msgstr ""
#. type: Plain text
-#: build/C/man2/fallocate.2:124
+#: build/C/man2/fallocate.2:247
msgid "A signal was caught during execution."
msgstr ""
#. type: Plain text
-#: build/C/man2/fallocate.2:136 build/C/man3/posix_fallocate.3:85
+#: build/C/man2/fallocate.2:259 build/C/man3/posix_fallocate.3:87
msgid "I<offset> was less than 0, or I<len> was less than or equal to 0."
msgstr ""
+#. type: Plain text
+#: build/C/man2/fallocate.2:269
+msgid ""
+"I<mode> is B<FALLOC_FL_COLLAPSE_RANGE> and the range specified by I<offset> "
+"plus I<len> reaches or passes the end of the file."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/fallocate.2:279
+msgid ""
+"I<mode> is B<FALLOC_FL_COLLAPSE_RANGE>, but either I<offset> or I<len> is "
+"not a multiple of the filesystem block size."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/fallocate.2:287
+msgid ""
+"I<mode> contains both B<FALLOC_FL_COLLAPSE_RANGE> and other flags; no other "
+"flags are permitted with B<FALLOC_FL_COLLAPSE_RANGE>."
+msgstr ""
+
+#. There was a inconsistency in 3.15-rc1, that should be resolved so that all
+#. filesystems use this error for this case. (Tytso says ex4 will change.)
+#. http://thread.gmane.org/gmane.comp.file-systems.xfs.general/60485/focus=5521
+#. From: Michael Kerrisk (man-pages <mtk.manpages@...>
+#. Subject: Re: [PATCH v5 10/10] manpage: update FALLOC_FL_COLLAPSE_RANGE flag in fallocate
+#. Newsgroups: gmane.linux.man, gmane.linux.file-systems
+#. Date: 2014-04-17 13:40:05 GMT
+#. type: Plain text
+#: build/C/man2/fallocate.2:304
+msgid ""
+"I<mode> is B<FALLOC_FL_COLLAPSE_RANGE> or B<FALLOC_FL_ZERO_RANGE>, but the "
+"file referred to by I<fd> is not a regular file."
+msgstr ""
+
#. type: TP
-#: build/C/man2/fallocate.2:136 build/C/man2/madvise.2:292 build/C/man2/sync_file_range.2:160
+#: build/C/man2/fallocate.2:304 build/C/man2/madvise.2:310 build/C/man2/sync_file_range.2:160
#, no-wrap
msgid "B<EIO>"
msgstr ""
#. type: Plain text
-#: build/C/man2/fallocate.2:139
-msgid "An I/O error occurred while reading from or writing to a file system."
+#: build/C/man2/fallocate.2:307
+msgid "An I/O error occurred while reading from or writing to a filesystem."
msgstr ""
#. type: TP
-#: build/C/man2/fallocate.2:139 build/C/man2/mmap.2:450 build/C/man3/posix_fallocate.3:85
+#: build/C/man2/fallocate.2:307 build/C/man2/mmap.2:450 build/C/man3/posix_fallocate.3:87 build/C/man2/s390_pci_mmio_write.2:92
#, no-wrap
msgid "B<ENODEV>"
msgstr ""
#. type: Plain text
-#: build/C/man2/fallocate.2:146
+#: build/C/man2/fallocate.2:314
msgid ""
"I<fd> does not refer to a regular file or a directory. (If I<fd> is a pipe "
"or FIFO, a different error results.)"
msgstr ""
#. type: TP
-#: build/C/man2/fallocate.2:146 build/C/man3/posix_fallocate.3:89 build/C/man2/shmget.2:214 build/C/man2/sync_file_range.2:166
+#: build/C/man2/fallocate.2:314 build/C/man3/posix_fallocate.3:91 build/C/man2/shmget.2:233 build/C/man2/sync_file_range.2:166
#, no-wrap
msgid "B<ENOSPC>"
msgstr ""
#. type: Plain text
-#: build/C/man2/fallocate.2:151 build/C/man3/posix_fallocate.3:94
+#: build/C/man2/fallocate.2:319 build/C/man3/posix_fallocate.3:96
msgid ""
"There is not enough space left on the device containing the file referred to "
"by I<fd>."
msgstr ""
#. type: Plain text
-#: build/C/man2/fallocate.2:156
-msgid ""
-"The file system containing the file referred to by I<fd> does not support "
-"this operation."
+#: build/C/man2/fallocate.2:323
+msgid "This kernel does not implement B<fallocate>()."
msgstr ""
#. type: TP
-#: build/C/man2/fallocate.2:156
+#: build/C/man2/fallocate.2:323
#, no-wrap
msgid "B<EOPNOTSUPP>"
msgstr ""
#. type: Plain text
-#: build/C/man2/fallocate.2:162
+#: build/C/man2/fallocate.2:332
msgid ""
-"The I<mode> is not supported by the file system containing the file referred "
-"to by I<fd>."
+"The filesystem containing the file referred to by I<fd> does not support "
+"this operation; or the I<mode> is not supported by the filesystem containing "
+"the file referred to by I<fd>."
msgstr ""
#. type: TP
-#: build/C/man2/fallocate.2:162 build/C/man2/mlock.2:144 build/C/man2/mlock.2:183 build/C/man2/mmap.2:458 build/C/man2/shmctl.2:342 build/C/man2/shmget.2:222
+#: build/C/man2/fallocate.2:332 build/C/man2/fallocate.2:338 build/C/man2/fallocate.2:351 build/C/man2/mlock.2:143 build/C/man2/mlock.2:182 build/C/man2/mmap.2:458 build/C/man2/mmap.2:467 build/C/man2/shmctl.2:353 build/C/man2/shmget.2:241
#, no-wrap
msgid "B<EPERM>"
msgstr ""
#. type: Plain text
-#: build/C/man2/fallocate.2:178
+#: build/C/man2/fallocate.2:338
+msgid "The file referred to by I<fd> is marked immutable (see B<chattr>(1))."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/fallocate.2:351
msgid ""
-"The file referred to by I<fd> is marked immutable (see B<chattr>(1)). Or: "
-"I<mode> specifies B<FALLOC_FL_PUNCH_HOLE> and the file referred to by I<fd> "
-"is marked append-only (see B<chattr>(1))."
+"I<mode> specifies B<FALLOC_FL_PUNCH_HOLE> or B<FALLOC_FL_COLLAPSE_RANGE> and "
+"the file referred to by I<fd> is marked append-only (see B<chattr>(1))."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/fallocate.2:355 build/C/man2/mmap.2:471
+msgid "The operation was prevented by a file seal; see B<fcntl>(2)."
msgstr ""
#. type: TP
-#: build/C/man2/fallocate.2:178 build/C/man2/posix_fadvise.2:96 build/C/man3/posix_fallocate.3:94 build/C/man2/sync_file_range.2:169
+#: build/C/man2/fallocate.2:355 build/C/man2/posix_fadvise.2:97 build/C/man3/posix_fallocate.3:96 build/C/man2/sync_file_range.2:169
#, no-wrap
msgid "B<ESPIPE>"
msgstr ""
#. type: Plain text
-#: build/C/man2/fallocate.2:182
+#: build/C/man2/fallocate.2:359
msgid "I<fd> refers to a pipe or FIFO."
msgstr ""
+#. type: TP
+#: build/C/man2/fallocate.2:359 build/C/man2/mmap.2:471
+#, no-wrap
+msgid "B<ETXTBSY>"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/fallocate.2:367
+msgid ""
+"I<mode> specifies B<FALLOC_FL_COLLAPSE_RANGE>, but the file referred to by "
+"I<fd> is currently being executed."
+msgstr ""
+
#. type: SH
-#: build/C/man2/fallocate.2:182 build/C/man2/mmap2.2:74 build/C/man2/posix_fadvise.2:103 build/C/man3/posix_fallocate.3:98 build/C/man3/posix_memalign.3:165 build/C/man2/readahead.2:82 build/C/man2/remap_file_pages.2:146 build/C/man3/shm_open.3:247 build/C/man2/subpage_prot.2:85 build/C/man2/sync_file_range.2:177
+#: build/C/man2/fallocate.2:367 build/C/man2/madvise.2:325 build/C/man3/malloc_info.3:60 build/C/man3/mcheck.3:134 build/C/man2/mmap2.2:74 build/C/man2/posix_fadvise.2:107 build/C/man3/posix_fallocate.3:100 build/C/man3/posix_memalign.3:167 build/C/man2/readahead.2:83 build/C/man2/remap_file_pages.2:156 build/C/man3/shm_open.3:249 build/C/man2/subpage_prot.2:90 build/C/man2/sync_file_range.2:177 build/C/man2/memfd_create.2:155 build/C/man2/s390_pci_mmio_write.2:98
#, no-wrap
msgid "VERSIONS"
msgstr ""
+#. See http://sourceware.org/bugzilla/show_bug.cgi?id=14964
#. type: Plain text
-#: build/C/man2/fallocate.2:186
+#: build/C/man2/fallocate.2:375
msgid ""
"B<fallocate>() is available on Linux since kernel 2.6.23. Support is "
-"provided by glibc since version 2.10."
+"provided by glibc since version 2.10. The B<FALLOC_FL_*> flags are defined "
+"in glibc headers only since version 2.18."
msgstr ""
#. type: Plain text
-#: build/C/man2/fallocate.2:189
+#: build/C/man2/fallocate.2:378
msgid "B<fallocate>() is Linux-specific."
msgstr ""
#. type: Plain text
-#: build/C/man2/fallocate.2:192
-msgid "B<ftruncate>(2), B<posix_fadvise>(3), B<posix_fallocate>(3)"
+#: build/C/man2/fallocate.2:383
+msgid "B<f
allocate>(1), B<ftruncate>(2), B<posix_fadvise>(3), B<posix_fallocate>(3)"
msgstr ""
#. type: TH
msgstr ""
#. type: TH
-#: build/C/man2/madvise.2:35
+#: build/C/man2/madvise.2:35 build/C/man2/posix_fadvise.2:28
#, no-wrap
-msgid "2011-09-18"
+msgid "2014-12-31"
msgstr ""
#. type: Plain text
msgstr ""
#. type: Plain text
-#: build/C/man2/madvise.2:46 build/C/man2/posix_fadvise.2:42 build/C/man3/posix_fallocate.3:37 build/C/man3/posix_memalign.3:48
+#: build/C/man2/madvise.2:46 build/C/man2/posix_fadvise.2:43 build/C/man3/posix_fallocate.3:39 build/C/man3/posix_memalign.3:49
msgid "Feature Test Macro Requirements for glibc (see B<feature_test_macros>(7)):"
msgstr ""
#. type: TP
#: build/C/man2/madvise.2:100
#, no-wrap
-msgid "B<MADV_REMOVE> (Since Linux 2.6.16)"
+msgid "B<MADV_REMOVE> (since Linux 2.6.16)"
msgstr ""
#. 2.6.18-rc5
#: build/C/man2/madvise.2:113
msgid ""
"Free up a given range of pages and its associated backing store. Currently, "
-"only shmfs/tmpfs supports this; other file systems return with the error "
+"only shmfs/tmpfs supports this; other filesystems return with the error "
"B<ENOSYS>."
msgstr ""
#. type: TP
#: build/C/man2/madvise.2:113
#, no-wrap
-msgid "B<MADV_DONTFORK> (Since Linux 2.6.16)"
+msgid "B<MADV_DONTFORK> (since Linux 2.6.16)"
msgstr ""
#. See http://lwn.net/Articles/171941/
#. type: TP
#: build/C/man2/madvise.2:144
#, no-wrap
-msgid "B<MADV_DOFORK> (Since Linux 2.6.16)"
+msgid "B<MADV_DOFORK> (since Linux 2.6.16)"
msgstr ""
#. type: Plain text
#. type: TP
#: build/C/man2/madvise.2:150
#, no-wrap
-msgid "B<MADV_HWPOISON> (Since Linux 2.6.32)"
+msgid "B<MADV_HWPOISON> (since Linux 2.6.32)"
msgstr ""
#. type: Plain text
#: build/C/man2/madvise.2:162
msgid ""
"Poison a page and handle it like a hardware memory corruption. This "
-"operation is only available for privileged (B<CAP_SYS_ADMIN>) processes. "
+"operation is available only for privileged (B<CAP_SYS_ADMIN>) processes. "
"This operation may result in the calling process receiving a B<SIGBUS> and "
"the page being unmapped. This feature is intended for testing of memory "
-"error-handling code; it is only available if the kernel was configured with "
+"error-handling code; it is available only if the kernel was configured with "
"B<CONFIG_MEMORY_FAILURE>."
msgstr ""
#. type: TP
#: build/C/man2/madvise.2:162
#, no-wrap
-msgid "B<MADV_SOFT_OFFLINE> (Since Linux 2.6.33)"
+msgid "B<MADV_SOFT_OFFLINE> (since Linux 2.6.33)"
msgstr ""
#. type: Plain text
"out of normal memory management). The effect of the B<MADV_SOFT_OFFLINE> "
"operation is invisible to (i.e., does not change the semantics of) the "
"calling process. This feature is intended for testing of memory "
-"error-handling code; it is only available if the kernel was configured with "
+"error-handling code; it is available only if the kernel was configured with "
"B<CONFIG_MEMORY_FAILURE>."
msgstr ""
"memory that have been marked as mergeable, looking for pages with identical "
"content. These are replaced by a single write-protected page (which is "
"automatically copied if a process later wants to update the content of the "
-"page). KSM only merges private anonymous pages (see B<mmap>(2)). The KSM "
+"page). KSM merges only private anonymous pages (see B<mmap>(2)). The KSM "
"feature is intended for applications that generate many instances of the "
"same data (e.g., virtualization systems such as KVM). It can consume a lot "
-"of processing power; use with care. See the kernel source file "
+"of processing power; use with care. See the Linux kernel source file "
"I<Documentation/vm/ksm.txt> for more details. The B<MADV_MERGEABLE> and "
-"B<MADV_UNMERGEABLE> operations are only available if the kernel was "
+"B<MADV_UNMERGEABLE> operations are available only if the kernel was "
"configured with B<CONFIG_KSM>."
msgstr ""
#: build/C/man2/madvise.2:243
msgid ""
"Enables Transparent Huge Pages (THP) for pages in the range specified by "
-"I<addr> and I<length>. Currently, Transparent Huge Pages only work with "
+"I<addr> and I<length>. Currently, Transparent Huge Pages work only with "
"private anonymous pages (see B<mmap>(2)). The kernel will regularly scan "
"the areas marked as huge page candidates to replace them with huge pages. "
"The kernel will also allocate huge pages directly when the region is "
"naturally aligned to the huge page size (see B<posix_memalign>(2)). This "
"feature is primarily aimed at applications that use large mappings of data "
-"and access large regions of that memory at a time (e.g. virtualization "
-"systems such as QEMU). It can very easily waste memory (e.g. a 2MB mapping "
+"and access large regions of that memory at a time (e.g., virtualization "
+"systems such as QEMU). It can very easily waste memory (e.g., a 2MB mapping "
"that only ever accesses 1 byte will result in 2MB of wired memory instead of "
-"one 4KB page). See the kernel source file I<Documentation/vm/transhuge.txt> "
-"for more details. The B<MADV_HUGEPAGE> and B<MADV_NOHUGEPAGE> operations "
-"are only available if the kernel was configured with "
-"B<CONFIG_TRANSPARENT_HUGEPAGE>."
+"one 4KB page). See the Linux kernel source file "
+"I<Documentation/vm/transhuge.txt> for more details. The B<MADV_HUGEPAGE> "
+"and B<MADV_NOHUGEPAGE> operations are available only if the kernel was "
+"configured with B<CONFIG_TRANSPARENT_HUGEPAGE>."
msgstr ""
#. type: TP
"will not be collapsed into huge pages."
msgstr ""
+#. type: TP
+#: build/C/man2/madvise.2:250
+#, no-wrap
+msgid "B<MADV_DONTDUMP> (since Linux 3.4)"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/madvise.2:264
+msgid ""
+"Exclude from a core dump those pages in the range specified by I<addr> and "
+"I<length>. This is useful in applications that have large areas of memory "
+"that are known not to be useful in a core dump. The effect of "
+"B<MADV_DONTDUMP> takes precedence over the bit mask that is set via the "
+"I</proc/PID/coredump_filter> file (see B<core>(5))."
+msgstr ""
+
+#. type: TP
+#: build/C/man2/madvise.2:264
+#, no-wrap
+msgid "B<MADV_DODUMP> (since Linux 3.4)"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/madvise.2:268
+msgid "Undo the effect of an earlier B<MADV_DONTDUMP>."
+msgstr ""
+
#. type: Plain text
-#: build/C/man2/madvise.2:257
+#: build/C/man2/madvise.2:275
msgid ""
"On success B<madvise>() returns zero. On error, it returns -1 and I<errno> "
"is set appropriately."
msgstr ""
#. type: TP
-#: build/C/man2/madvise.2:258 build/C/man2/mlock.2:155 build/C/man2/mmap.2:411 build/C/man2/mremap.2:137
+#: build/C/man2/madvise.2:276 build/C/man2/mlock.2:154 build/C/man2/mmap.2:411 build/C/man2/mremap.2:136
#, no-wrap
msgid "B<EAGAIN>"
msgstr ""
#. type: Plain text
-#: build/C/man2/madvise.2:261
+#: build/C/man2/madvise.2:279
msgid "A kernel resource was temporarily unavailable."
msgstr ""
#. type: Plain text
-#: build/C/man2/madvise.2:264
+#: build/C/man2/madvise.2:282
msgid "The map exists, but the area maps something that isn't a file."
msgstr ""
#. type: Plain text
-#: build/C/man2/madvise.2:267
+#: build/C/man2/madvise.2:285
msgid "This error can occur for the following reasons:"
msgstr ""
-#. type: IP
-#: build/C/man2/madvise.2:268 build/C/man2/madvise.2:274 build/C/man2/madvise.2:277 build/C/man2/madvise.2:280 build/C/man2/madvise.2:283 build/C/man3/mallopt.3:233 build/C/man3/mallopt.3:239
-#, no-wrap
-msgid "*"
-msgstr ""
-
#. .I len
#. is zero,
#. type: Plain text
-#: build/C/man2/madvise.2:274
+#: build/C/man2/madvise.2:292
msgid "The value I<len> is negative."
msgstr ""
#. type: Plain text
-#: build/C/man2/madvise.2:277
+#: build/C/man2/madvise.2:295
msgid "I<addr> is not page-aligned."
msgstr ""
#. type: Plain text
-#: build/C/man2/madvise.2:280
+#: build/C/man2/madvise.2:298
msgid "I<advice> is not a valid value"
msgstr ""
#. type: Plain text
-#: build/C/man2/madvise.2:283
+#: build/C/man2/madvise.2:301
msgid ""
"The application is attempting to release locked or shared pages (with "
"B<MADV_DONTNEED>)."
msgstr ""
#. type: Plain text
-#: build/C/man2/madvise.2:291
+#: build/C/man2/madvise.2:309
msgid ""
"B<MADV_MERGEABLE> or B<MADV_UNMERGEABLE> was specified in I<advice>, but the "
"kernel was not configured with B<CONFIG_KSM>."
msgstr ""
#. type: Plain text
-#: build/C/man2/madvise.2:298
+#: build/C/man2/madvise.2:316
msgid ""
"(for B<MADV_WILLNEED>) Paging in this area would exceed the process's "
"maximum resident set size."
msgstr ""
#. type: TP
-#: build/C/man2/madvise.2:298 build/C/man2/madvise.2:303 build/C/man2/mlock.2:124 build/C/man2/mlock.2:132 build/C/man2/mlock.2:170 build/C/man2/mmap.2:454 build/C/man2/mprotect.2:94 build/C/man2/mprotect.2:97 build/C/man2/mremap.2:180 build/C/man2/msync.2:93 build/C/man3/posix_memalign.3:162 build/C/man2/shmctl.2:326 build/C/man2/shmget.2:211 build/C/man2/shmop.2:209 build/C/man2/subpage_prot.2:82 build/C/man2/sync_file_range.2:163
+#: build/C/man2/madvise.2:316 build/C/man2/madvise.2:321 build/C/man2/mlock.2:123 build/C/man2/mlock.2:131 build/C/man2/mlock.2:169 build/C/man2/mmap.2:454 build/C/man2/mprotect.2:99 build/C/man2/mprotect.2:102 build/C/man2/mremap.2:179 build/C/man2/msync.2:93 build/C/man3/posix_memalign.3:164 build/C/man2/shmctl.2:337 build/C/man2/shmget.2:230 build/C/man2/shmop.2:211 build/C/man2/subpage_prot.2:87 build/C/man2/sync_file_range.2:163 build/C/man2/memfd_create.2:152 build/C/man2/s390_pci_mmio_write.2:95
#, no-wrap
msgid "B<ENOMEM>"
msgstr ""
#. type: Plain text
-#: build/C/man2/madvise.2:303
+#: build/C/man2/madvise.2:321
msgid "(for B<MADV_WILLNEED>) Not enough memory: paging in failed."
msgstr ""
#. type: Plain text
-#: build/C/man2/madvise.2:307
+#: build/C/man2/madvise.2:325
msgid ""
"Addresses in the specified range are not currently mapped, or are outside "
"the address space of the process."
msgstr ""
-#. FIXME . Write a posix_fadvise(3) page.
+#. commit d3ac21cacc24790eb45d735769f35753f5b56ceb
+#. type: Plain text
+#: build/C/man2/madvise.2:332
+msgid ""
+"Since Linux 3.18, support for this system call is optional, depending on the "
+"setting of the B<CONFIG_ADVISE_SYSCALLS> configuration option."
+msgstr ""
+
+#. FIXME . Write a posix_madvise(3) page.
#. type: Plain text
-#: build/C/man2/madvise.2:319
+#: build/C/man2/madvise.2:345
msgid ""
"POSIX.1b. POSIX.1-2001 describes B<posix_madvise>(3) with constants "
-"B<POSIX_MADV_NORMAL>, etc., with a behavior close to that described here. "
-"There is a similar B<posix_fadvise>(2) for file access."
+"B<POSIX_MADV_NORMAL>, B<POSIX_MADV_RANDOM>, and so on, with a behavior close "
+"to that described here. There is a similar B<posix_fadvise>(2) for file "
+"access."
msgstr ""
#. type: Plain text
-#: build/C/man2/madvise.2:328
+#: build/C/man2/madvise.2:354
msgid ""
"B<MADV_REMOVE>, B<MADV_DONTFORK>, B<MADV_DOFORK>, B<MADV_HWPOISON>, "
"B<MADV_MERGEABLE>, and B<MADV_UNMERGEABLE> are Linux-specific."
msgstr ""
#. type: SS
-#: build/C/man2/madvise.2:329 build/C/man2/mlock.2:268 build/C/man2/shmget.2:278
+#: build/C/man2/madvise.2:355 build/C/man2/mlock.2:274 build/C/man2/shmget.2:370
#, no-wrap
-msgid "Linux Notes"
+msgid "Linux notes"
msgstr ""
#. type: Plain text
-#: build/C/man2/madvise.2:337
+#: build/C/man2/madvise.2:363
msgid ""
"The current Linux implementation (2.4.0) views this system call more as a "
"command than as advice and hence may return an error when it cannot do what "
#. .BR madvise ()
#. function first appeared in 4.4BSD.
#. type: Plain text
-#: build/C/man2/madvise.2:353
+#: build/C/man2/madvise.2:379
msgid ""
"The Linux implementation requires that the address I<addr> be page-aligned, "
"and allows I<length> to be zero. If there are some parts of the specified "
msgstr ""
#. type: Plain text
-#: build/C/man2/madvise.2:359
+#: build/C/man2/madvise.2:388
msgid ""
"B<getrlimit>(2), B<mincore>(2), B<mmap>(2), B<mprotect>(2), B<msync>(2), "
-"B<munmap>(2)"
+"B<munmap>(2), B<prctl>(2), B<core>(5)"
msgstr ""
#. type: TH
-#: build/C/man3/malloc_hook.3:6
+#: build/C/man3/mallinfo.3:26
#, no-wrap
-msgid "MALLOC_HOOK"
+msgid "MALLINFO"
msgstr ""
#. type: TH
-#: build/C/man3/malloc_hook.3:6
+#: build/C/man3/mallinfo.3:26 build/C/man3/malloc_stats.3:26
#, no-wrap
-msgid "2010-10-13"
+msgid "2012-05-06"
msgstr ""
#. type: Plain text
-#: build/C/man3/malloc_hook.3:11
-msgid ""
-"__malloc_hook, __malloc_initialize_hook, __memalign_hook, __free_hook, "
-"__realloc_hook, __after_morecore_hook - malloc debugging variables"
+#: build/C/man3/mallinfo.3:29
+msgid "mallinfo - obtain memory allocation information"
msgstr ""
#. type: Plain text
-#: build/C/man3/malloc_hook.3:14 build/C/man3/posix_memalign.3:40
-#, no-wrap
-msgid "B<#include E<lt>malloc.hE<gt>>\n"
+#: build/C/man3/mallinfo.3:31 build/C/man3/malloc_stats.3:31 build/C/man3/malloc_trim.3:31 build/C/man3/malloc_usable_size.3:30 build/C/man3/mallopt.3:31
+msgid "B<#include E<lt>malloc.hE<gt>>"
msgstr ""
#. type: Plain text
-#: build/C/man3/malloc_hook.3:16
-#, no-wrap
-msgid "B<void *(*__malloc_hook)(size_t >I<size>B<, const void *>I<caller>B<);>\n"
+#: build/C/man3/mallinfo.3:33
+msgid "B<struct mallinfo mallinfo(void);>"
msgstr ""
#. type: Plain text
-#: build/C/man3/malloc_hook.3:19
-#, no-wrap
+#: build/C/man3/mallinfo.3:41
msgid ""
-"B<void *(*__realloc_hook)(void *>I<ptr>B<, size_t >I<size>B<, const void "
-"*>I<caller>B<);>\n"
+"The B<mallinfo>() function returns a copy of a structure containing "
+"information about memory allocations performed by B<malloc>(3) and related "
+"functions. This structure is defined as follows:"
msgstr ""
#. type: Plain text
-#: build/C/man3/malloc_hook.3:22
+#: build/C/man3/mallinfo.3:56
#, no-wrap
msgid ""
-"B<void *(*__memalign_hook)(size_t >I<alignment>B<, size_t >I<size>B<,>\n"
-"B< const void *>I<caller>B<);>\n"
+"struct mallinfo {\n"
+" int arena; /* Non-mmapped space allocated (bytes) */\n"
+" int ordblks; /* Number of free chunks */\n"
+" int smblks; /* Number of free fastbin blocks */\n"
+" int hblks; /* Number of mmapped regions */\n"
+" int hblkhd; /* Space allocated in mmapped regions (bytes) */\n"
+" int usmblks; /* Maximum total allocated space (bytes) */\n"
+" int fsmblks; /* Space in freed fastbin blocks (bytes) */\n"
+" int uordblks; /* Total allocated space (bytes) */\n"
+" int fordblks; /* Total free space (bytes) */\n"
+" int keepcost; /* Top-most, releasable space (bytes) */\n"
+"};\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/malloc_hook.3:24
+#: build/C/man3/mallinfo.3:62
+msgid "The fields of the I<mallinfo> structure contain the following information:"
+msgstr ""
+
+#. type: TP
+#: build/C/man3/mallinfo.3:62
#, no-wrap
-msgid "B<void (*__free_hook)(void *>I<ptr>B<, const void *>I<caller>B<);>\n"
+msgid "I<arena>"
msgstr ""
#. type: Plain text
-#: build/C/man3/malloc_hook.3:26
+#: build/C/man3/mallinfo.3:68
+msgid ""
+"The total amount of memory allocated by means other than B<mmap>(2) (i.e., "
+"memory allocated on the heap). This figure includes both in-use blocks and "
+"blocks on the free list."
+msgstr ""
+
+#. type: TP
+#: build/C/man3/mallinfo.3:68
#, no-wrap
-msgid "B<void (*__malloc_initialize_hook)(void);>\n"
+msgid "I<ordblks>"
msgstr ""
#. type: Plain text
-#: build/C/man3/malloc_hook.3:28
+#: build/C/man3/mallinfo.3:71
+msgid "The number of ordinary (i.e., non-fastbin) free blocks."
+msgstr ""
+
+#. type: TP
+#: build/C/man3/mallinfo.3:71
#, no-wrap
-msgid "B<void (*__after_morecore_hook)(void);>\n"
+msgid "I<smblks>"
msgstr ""
#. type: Plain text
-#: build/C/man3/malloc_hook.3:39
-msgid ""
-"The GNU C library lets you modify the behavior of B<malloc>(3), "
-"B<realloc>(3), and B<free>(3) by specifying appropriate hook functions. "
-"You can use these hooks to help you debug programs that use dynamic memory "
-"allocation, for example."
+#: build/C/man3/mallinfo.3:75
+msgid "The number of fastbin free blocks (see B<mallopt>(3))."
+msgstr ""
+
+#. type: TP
+#: build/C/man3/mallinfo.3:75
+#, no-wrap
+msgid "I<hblks>"
msgstr ""
#. type: Plain text
-#: build/C/man3/malloc_hook.3:46
+#: build/C/man3/mallinfo.3:83
msgid ""
-"The variable B<__malloc_initialize_hook> points at a function that is called "
-"once when the malloc implementation is initialized. This is a weak "
-"variable, so it can be overridden in the application with a definition like "
-"the following:"
+"The number of blocks currently allocated using B<mmap>(2). (See the "
+"discussion of B<M_MMAP_THRESHOLD> in B<mallopt>(3).)"
msgstr ""
-#. type: Plain text
-#: build/C/man3/malloc_hook.3:49
+#. type: TP
+#: build/C/man3/mallinfo.3:83
#, no-wrap
-msgid " void (*__malloc_initialize_hook)(void) = my_init_hook;\n"
+msgid "I<hblkhd>"
msgstr ""
#. type: Plain text
-#: build/C/man3/malloc_hook.3:54
-msgid "Now the function I<my_init_hook>() can do the initialization of all hooks."
+#: build/C/man3/mallinfo.3:87
+msgid "The number of bytes in blocks currently allocated using B<mmap>(2)."
msgstr ""
-#. type: Plain text
-#: build/C/man3/malloc_hook.3:70
-msgid ""
-"The four functions pointed to by B<__malloc_hook>, B<__realloc_hook>, "
-"B<__memalign_hook>, B<__free_hook> have a prototype like the functions "
-"B<malloc>(3), B<realloc>(3), B<memalign>(3), B<free>(3), respectively, "
-"except that they have a final argument I<caller> that gives the address of "
-"the caller of B<malloc>(3), etc."
+#. type: TP
+#: build/C/man3/mallinfo.3:87
+#, no-wrap
+msgid "I<usmblks>"
msgstr ""
#. type: Plain text
-#: build/C/man3/malloc_hook.3:76
+#: build/C/man3/mallinfo.3:92
msgid ""
-"The variable B<__after_morecore_hook> points at a function that is called "
-"each time after B<sbrk>(2) was asked for more memory."
+"The \"highwater mark\" for allocated space\\(emthat is, the maximum amount "
+"of space that was ever allocated. This field is maintained only in "
+"nonthreading environments."
msgstr ""
-#. type: Plain text
-#: build/C/man3/malloc_hook.3:78 build/C/man3/mtrace.3:78
-msgid "These functions are GNU extensions."
+#. type: TP
+#: build/C/man3/mallinfo.3:92
+#, no-wrap
+msgid "I<fsmblks>"
msgstr ""
-#. https://bugzilla.redhat.com/show_bug.cgi?id=450187
-#. http://sourceware.org/bugzilla/show_bug.cgi?id=9957
#. type: Plain text
-#: build/C/man3/malloc_hook.3:85
-msgid ""
-"The use of these hook functions is not safe in multithreaded programs, and "
-"they are now deprecated. Programmers should instead preempt calls to the "
-"relevant functions by defining and exporting functions such as \"malloc\" "
-"and \"free\"."
+#: build/C/man3/mallinfo.3:95
+msgid "The total number of bytes in fastbin free blocks."
msgstr ""
-#. type: SH
-#: build/C/man3/malloc_hook.3:85 build/C/man3/mallopt.3:464 build/C/man2/mmap.2:571 build/C/man2/mprotect.2:142 build/C/man3/mtrace.3:106
+#. type: TP
+#: build/C/man3/mallinfo.3:95
#, no-wrap
-msgid "EXAMPLE"
+msgid "I<uordblks>"
msgstr ""
#. type: Plain text
-#: build/C/man3/malloc_hook.3:87
-msgid "Here is a short example of how to use these variables."
+#: build/C/man3/mallinfo.3:98
+msgid "The total number of bytes used by in-use allocations."
msgstr ""
-#. type: Plain text
-#: build/C/man3/malloc_hook.3:91
+#. type: TP
+#: build/C/man3/mallinfo.3:98
#, no-wrap
-msgid ""
-"#include E<lt>stdio.hE<gt>\n"
-"#include E<lt>malloc.hE<gt>\n"
+msgid "I<fordblks>"
msgstr ""
#. type: Plain text
-#: build/C/man3/malloc_hook.3:95
-#, no-wrap
-msgid ""
-"/* Prototypes for our hooks. */\n"
-"static void my_init_hook(void);\n"
-"static void *my_malloc_hook(size_t, const void *);\n"
+#: build/C/man3/mallinfo.3:101
+msgid "The total number of bytes in free blocks."
msgstr ""
-#. type: Plain text
-#: build/C/man3/malloc_hook.3:98
+#. type: TP
+#: build/C/man3/mallinfo.3:101
#, no-wrap
-msgid ""
-"/* Variables to save original hooks. */\n"
-"static void *(*old_malloc_hook)(size_t, const void *);\n"
+msgid "I<keepcost>"
msgstr ""
+#. .SH VERSIONS
+#. Available already in glibc 2.0, possibly earlier
#. type: Plain text
-#: build/C/man3/malloc_hook.3:101
-#, no-wrap
+#: build/C/man3/mallinfo.3:110
msgid ""
-"/* Override initializing hook from the C library. */\n"
-"void (*__malloc_initialize_hook) (void) = my_init_hook;\n"
+"The total amount of releasable free space at the top of the heap. This is "
+"the maximum number of bytes that could ideally (i.e., ignoring page "
+"alignment restrictions, and so on) be released by B<malloc_trim>(3)."
msgstr ""
#. type: Plain text
-#: build/C/man3/malloc_hook.3:108
-#, no-wrap
+#: build/C/man3/mallinfo.3:114
msgid ""
-"static void\n"
-"my_init_hook(void)\n"
-"{\n"
-" old_malloc_hook = __malloc_hook;\n"
-" __malloc_hook = my_malloc_hook;\n"
-"}\n"
+"This function is not specified by POSIX or the C standards. A similar "
+"function exists on many System V derivatives, and was specified in the SVID."
msgstr ""
+#. FIXME . http://sourceware.org/bugzilla/show_bug.cgi?id=208
+#. See the 24 Aug 2011 mail by Paul Pluzhnikov:
+#. "[patch] Fix mallinfo() to accumulate results for all arenas"
+#. on libc-alpha@sourceware.org
#. type: Plain text
-#: build/C/man3/malloc_hook.3:113
-#, no-wrap
+#: build/C/man3/mallinfo.3:126
msgid ""
-"static void *\n"
-"my_malloc_hook(size_t size, const void *caller)\n"
-"{\n"
-" void *result;\n"
+"B<Information is returned for only the main memory allocation area.> "
+"Allocations in other arenas are excluded. See B<malloc_stats>(3) and "
+"B<malloc_info>(3) for alternatives that include information about other "
+"arenas."
msgstr ""
#. type: Plain text
-#: build/C/man3/malloc_hook.3:116
-#, no-wrap
+#: build/C/man3/mallinfo.3:134
msgid ""
-" /* Restore all old hooks */\n"
-" __malloc_hook = old_malloc_hook;\n"
+"The fields of the I<mallinfo> structure are typed as I<int>. However, "
+"because some internal bookkeeping values may be of type I<long>, the "
+"reported values may wrap around zero and thus be inaccurate."
msgstr ""
-#. type: Plain text
-#: build/C/man3/malloc_hook.3:119
+#. type: SH
+#: build/C/man3/mallinfo.3:134 build/C/man3/malloc_hook.3:89 build/C/man3/malloc_info.3:84 build/C/man3/mallopt.3:454 build/C/man3/mcheck.3:159 build/C/man2/mmap.2:633 build/C/man2/mprotect.2:147 build/C/man3/mtrace.3:108 build/C/man2/memfd_create.2:293
#, no-wrap
+msgid "EXAMPLE"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mallinfo.3:140
msgid ""
-" /* Call recursively */\n"
-" result = malloc(size);\n"
+"The program below employs B<mallinfo>() to retrieve memory allocation "
+"statistics before and after allocating and freeing some blocks of memory. "
+"The statistics are displayed on standard output."
msgstr ""
#. type: Plain text
-#: build/C/man3/malloc_hook.3:122
-#, no-wrap
+#: build/C/man3/mallinfo.3:144
msgid ""
-" /* Save underlying hooks */\n"
-" old_malloc_hook = __malloc_hook;\n"
+"The first two command-line arguments specify the number and size of blocks "
+"to be allocated with B<malloc>(3)."
msgstr ""
#. type: Plain text
-#: build/C/man3/malloc_hook.3:126
-#, no-wrap
+#: build/C/man3/mallinfo.3:158
msgid ""
-" /* printf() might call malloc(), so protect it too. */\n"
-" printf(\"malloc(%u) called from %p returns %p\\en\",\n"
-" (unsigned int) size, caller, result);\n"
+"The remaining three arguments specify which of the allocated blocks should "
+"be freed with B<free>(3). These three arguments are optional, and specify "
+"(in order): the step size to be used in the loop that frees blocks (the "
+"default is 1, meaning free all blocks in the range); the ordinal position of "
+"the first block to be freed (default 0, meaning the first allocated block); "
+"and a number one greater than the ordinal position of the last block to be "
+"freed (default is one greater than the maximum block number). If these "
+"three arguments are omitted, then the defaults cause all allocated blocks to "
+"be freed."
msgstr ""
#. type: Plain text
-#: build/C/man3/malloc_hook.3:129
-#, no-wrap
+#: build/C/man3/mallinfo.3:162
msgid ""
-" /* Restore our own hooks */\n"
-" __malloc_hook = my_malloc_hook;\n"
+"In the following example run of the program, 1000 allocations of 100 bytes "
+"are performed, and then every second allocated block is freed:"
msgstr ""
#. type: Plain text
-#: build/C/man3/malloc_hook.3:132
+#: build/C/man3/mallinfo.3:177
#, no-wrap
msgid ""
-" return result;\n"
-"}\n"
+"$ B<./a.out 1000 100 2>\n"
+"============== Before allocating blocks ==============\n"
+"Total non-mmapped bytes (arena): 0\n"
+"# of free chunks (ordblks): 1\n"
+"# of free fastbin blocks (smblks): 0\n"
+"# of mapped regions (hblks): 0\n"
+"Bytes in mapped regions (hblkhd): 0\n"
+"Max. total allocated space (usmblks): 0\n"
+"Free bytes held in fastbins (fsmblks): 0\n"
+"Total allocated space (uordblks): 0\n"
+"Total free space (fordblks): 0\n"
+"Topmost releasable block (keepcost): 0\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/malloc_hook.3:137
-msgid "B<mallinfo>(3), B<malloc>(3), B<mcheck>(3), B<mtrace>(3)"
+#: build/C/man3/mallinfo.3:189
+#, no-wrap
+msgid ""
+"============== After allocating blocks ==============\n"
+"Total non-mmapped bytes (arena): 135168\n"
+"# of free chunks (ordblks): 1\n"
+"# of free fastbin blocks (smblks): 0\n"
+"# of mapped regions (hblks): 0\n"
+"Bytes in mapped regions (hblkhd): 0\n"
+"Max. total allocated space (usmblks): 0\n"
+"Free bytes held in fastbins (fsmblks): 0\n"
+"Total allocated space (uordblks): 104000\n"
+"Total free space (fordblks): 31168\n"
+"Topmost releasable block (keepcost): 31168\n"
msgstr ""
-#. type: TH
-#: build/C/man3/mallopt.3:24
+#. type: Plain text
+#: build/C/man3/mallinfo.3:201
#, no-wrap
-msgid "MALLOPT"
+msgid ""
+"============== After freeing blocks ==============\n"
+"Total non-mmapped bytes (arena): 135168\n"
+"# of free chunks (ordblks): 501\n"
+"# of free fastbin blocks (smblks): 0\n"
+"# of mapped regions (hblks): 0\n"
+"Bytes in mapped regions (hblkhd): 0\n"
+"Max. total allocated space (usmblks): 0\n"
+"Free bytes held in fastbins (fsmblks): 0\n"
+"Total allocated space (uordblks): 52000\n"
+"Total free space (fordblks): 83168\n"
+"Topmost releasable block (keepcost): 31168\n"
msgstr ""
-#. type: TH
-#: build/C/man3/mallopt.3:24
+#. type: SS
+#: build/C/man3/mallinfo.3:203 build/C/man3/malloc_info.3:167 build/C/man3/mallopt.3:520 build/C/man3/mcheck.3:176 build/C/man2/mmap.2:645 build/C/man2/mprotect.2:164
#, no-wrap
-msgid "2012-04-17"
+msgid "Program source"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:27
-msgid "mallopt - set memory allocation parameters"
+#: build/C/man3/mallinfo.3:208
+#, no-wrap
+msgid ""
+"#include E<lt>malloc.hE<gt>\n"
+"#include \"tlpi_hdr.h\"\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:29
-msgid "B<#include E<lt>malloc.hE<gt>>"
+#: build/C/man3/mallinfo.3:213
+#, no-wrap
+msgid ""
+"static void\n"
+"display_mallinfo(void)\n"
+"{\n"
+" struct mallinfo mi;\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:31
-msgid "B<int mallopt(int >I<param>B<, int >I<value>B<);>"
+#: build/C/man3/mallinfo.3:215
+#, no-wrap
+msgid " mi = mallinfo();\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:42
+#: build/C/man3/mallinfo.3:227
+#, no-wrap
msgid ""
-"The B<mallopt>() function adjusts parameters that control the behavior of "
-"the memory-allocation functions (see B<malloc>(3)). The I<param> argument "
-"specifies the parameter to be modified, and I<value> specifies the new value "
-"for that parameter."
+" printf(\"Total non-mmapped bytes (arena): %d\\en\", mi.arena);\n"
+" printf(\"# of free chunks (ordblks): %d\\en\", mi.ordblks);\n"
+" printf(\"# of free fastbin blocks (smblks): %d\\en\", mi.smblks);\n"
+" printf(\"# of mapped regions (hblks): %d\\en\", mi.hblks);\n"
+" printf(\"Bytes in mapped regions (hblkhd): %d\\en\", mi.hblkhd);\n"
+" printf(\"Max. total allocated space (usmblks): %d\\en\", mi.usmblks);\n"
+" printf(\"Free bytes held in fastbins (fsmblks): %d\\en\", mi.fsmblks);\n"
+" printf(\"Total allocated space (uordblks): %d\\en\", "
+"mi.uordblks);\n"
+" printf(\"Total free space (fordblks): %d\\en\", "
+"mi.fordblks);\n"
+" printf(\"Topmost releasable block (keepcost): %d\\en\", "
+"mi.keepcost);\n"
+"}\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:45
-msgid "The following values can be specified for I<param>:"
+#: build/C/man3/mallinfo.3:235
+#, no-wrap
+msgid ""
+"int\n"
+"main(int argc, char *argv[])\n"
+"{\n"
+"#define MAX_ALLOCS 2000000\n"
+" char *alloc[MAX_ALLOCS];\n"
+" int numBlocks, j, freeBegin, freeEnd, freeStep;\n"
+" size_t blockSize;\n"
msgstr ""
-#. type: TP
-#: build/C/man3/mallopt.3:45
+#. type: Plain text
+#: build/C/man3/mallinfo.3:239
#, no-wrap
-msgid "B<M_CHECK_ACTION>"
+msgid ""
+" if (argc E<lt> 3 || strcmp(argv[1], \"--help\") == 0)\n"
+" usageErr(\"%s num-blocks block-size [free-step [start-free \"\n"
+" \"[end-free]]]\\en\", argv[0]);\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:51
+#: build/C/man3/mallinfo.3:245
+#, no-wrap
msgid ""
-"Setting this parameter controls how glibc responds when various kinds of "
-"programming errors are detected (e.g., freeing the same pointer twice). The "
-"3 least significant bits (2, 1, and 0) of the value assigned to this "
-"parameter determine the glibc behavior, as follows:"
+" numBlocks = atoi(argv[1]);\n"
+" blockSize = atoi(argv[2]);\n"
+" freeStep = (argc E<gt> 3) ? atoi(argv[3]) : 1;\n"
+" freeBegin = (argc E<gt> 4) ? atoi(argv[4]) : 0;\n"
+" freeEnd = (argc E<gt> 5) ? atoi(argv[5]) : numBlocks;\n"
msgstr ""
-#. type: TP
-#: build/C/man3/mallopt.3:52
+#. type: Plain text
+#: build/C/man3/mallinfo.3:248
#, no-wrap
-msgid "Bit 0"
+msgid ""
+" printf(\"============== Before allocating blocks "
+"==============\\en\");\n"
+" display_mallinfo();\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:62
+#: build/C/man3/mallinfo.3:252
+#, no-wrap
msgid ""
-"If this bit is set, then print a one-line message on I<stderr> that provides "
-"details about the error. The message starts with the string \"***\\ glibc "
-"detected\\ ***\", followed by the program name, the name of the "
-"memory-allocation function in which the error was detected, a brief "
-"description of the error, and the memory address where the error was "
-"detected."
+" for (j = 0; j E<lt> numBlocks; j++) {\n"
+" if (numBlocks E<gt>= MAX_ALLOCS)\n"
+" fatal(\"Too many allocations\");\n"
msgstr ""
-#. type: TP
-#: build/C/man3/mallopt.3:62
+#. type: Plain text
+#: build/C/man3/mallinfo.3:257
#, no-wrap
-msgid "Bit 1"
+msgid ""
+" alloc[j] = malloc(blockSize);\n"
+" if (alloc[j] == NULL)\n"
+" errExit(\"malloc\");\n"
+" }\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:77
+#: build/C/man3/mallinfo.3:260
+#, no-wrap
msgid ""
-"If this bit is set, then, after printing any error message specified by bit "
-"0, the program is terminated by calling B<abort>(3). In glibc versions "
-"since 2.4, if bit 0 is also set, then, between printing the error message "
-"and aborting, the program also prints a stack trace in the manner of "
-"B<backtrace>(3), and prints the process's memory mapping in the style of "
-"I</proc/[pid]/maps> (see B<proc>(5))."
+" printf(\"\\en============== After allocating blocks "
+"==============\\en\");\n"
+" display_mallinfo();\n"
msgstr ""
-#. type: TP
-#: build/C/man3/mallopt.3:77
+#. type: Plain text
+#: build/C/man3/mallinfo.3:263
#, no-wrap
-msgid "Bit 2 (since glibc 2.4)"
+msgid ""
+" for (j = freeBegin; j E<lt> freeEnd; j += freeStep)\n"
+" free(alloc[j]);\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:84
+#: build/C/man3/mallinfo.3:266
+#, no-wrap
msgid ""
-"This bit has an effect only if bit 0 is also set. If this bit is set, then "
-"the one-line message describing the error is simplified to contain just the "
-"name of the function where the error was detected and the brief description "
-"of the error."
+" printf(\"\\en============== After freeing blocks "
+"==============\\en\");\n"
+" display_mallinfo();\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:89
-msgid "The remaining bits in I<value> are ignored."
+#: build/C/man3/mallinfo.3:269 build/C/man3/malloc_info.3:255 build/C/man3/mallopt.3:553 build/C/man3/mcheck.3:203 build/C/man2/mmap.2:714 build/C/man2/memfd_create.2:437 build/C/man2/memfd_create.2:486
+#, no-wrap
+msgid ""
+" exit(EXIT_SUCCESS);\n"
+"}\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:93
+#: build/C/man3/mallinfo.3:279
msgid ""
-"Combining the above details, the following numeric values are meaningful for "
-"B<M_CHECK_ACTION>:"
+"B<mmap>(2), B<malloc>(3), B<malloc_info>(3), B<malloc_stats>(3), "
+"B<malloc_trim>(3), B<mallopt>(3)"
msgstr ""
-#. type: IP
-#: build/C/man3/mallopt.3:94
+#. type: TH
+#: build/C/man3/malloc_get_state.3:25
#, no-wrap
-msgid "0"
-msgstr ""
-
-#. type: Plain text
-#: build/C/man3/mallopt.3:96
-msgid "Ignore error conditions; continue execution (with undefined results)."
+msgid "MALLOC_GET_STATE"
msgstr ""
-#. type: IP
-#: build/C/man3/mallopt.3:96
+#. type: TH
+#: build/C/man3/malloc_get_state.3:25 build/C/man3/malloc_usable_size.3:25
#, no-wrap
-msgid "1"
+msgid "2014-06-13"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:98
-msgid "Print a detailed error message and continue execution."
+#: build/C/man3/malloc_get_state.3:28
+msgid ""
+"malloc_get_state, malloc_set_state - record and restore state of malloc "
+"implementation"
msgstr ""
-#. type: IP
-#: build/C/man3/mallopt.3:98
+#. type: Plain text
+#: build/C/man3/malloc_get_state.3:31 build/C/man3/malloc_hook.3:18 build/C/man3/malloc_info.3:31 build/C/man3/posix_memalign.3:41
#, no-wrap
-msgid "2"
+msgid "B<#include E<lt>malloc.hE<gt>>\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:100
-msgid "Abort the program."
-msgstr ""
-
-#. type: IP
-#: build/C/man3/mallopt.3:100
+#: build/C/man3/malloc_get_state.3:33
#, no-wrap
-msgid "3"
+msgid "B<void* malloc_get_state(void);>\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:103
-msgid ""
-"Print detailed error message, stack trace, and memory mappings, and abort "
-"the program."
-msgstr ""
-
-#. type: IP
-#: build/C/man3/mallopt.3:103
+#: build/C/man3/malloc_get_state.3:35
#, no-wrap
-msgid "5"
+msgid "B<int malloc_set_state(void *>I<state>B<);>\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:105
-msgid "Print a simple error message and continue execution."
-msgstr ""
-
-#. type: IP
-#: build/C/man3/mallopt.3:105
-#, no-wrap
-msgid "7"
+#: build/C/man3/malloc_get_state.3:53
+msgid ""
+"The B<malloc_get_state>() function records the current state of all "
+"B<malloc>(3) internal bookkeeping variables (but not the actual contents of "
+"the heap or the state of B<malloc_hook>(3) functions pointers). The state "
+"is recorded in a system-dependent opaque data structure dynamically "
+"allocated via B<malloc>(3), and a pointer to that data structure is returned "
+"as the function result. (It is the caller's responsibility to B<free>(3) "
+"this memory.)"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:108
+#: build/C/man3/malloc_get_state.3:61
msgid ""
-"Print simple error message, stack trace, and memory mappings, and abort the "
-"program."
+"The B<malloc_set_state>() function restores the state of all B<malloc>(3) "
+"internal bookkeeping variables to the values recorded in the opaque data "
+"structure pointed to by I<state>."
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:114
+#: build/C/man3/malloc_get_state.3:68
msgid ""
-"Since glibc 2.3.4, the default value for the B<M_CHECK_ACTION> parameter is "
-"3. In glibc version 2.3.3 and earlier, the default value is 1."
+"On success, B<malloc_get_state>() returns a pointer to a newly allocated "
+"opaque data structure. On error (for example, memory could not be allocated "
+"for the data structure), B<malloc_get_state>() returns NULL."
msgstr ""
+#. if(ms->magic != MALLOC_STATE_MAGIC) return -1;
+#. /* Must fail if the major version is too high. */
+#. if((ms->version & ~0xffl) > (MALLOC_STATE_VERSION & ~0xffl)) return -2;
#. type: Plain text
-#: build/C/man3/mallopt.3:119
+#: build/C/man3/malloc_get_state.3:86
msgid ""
-"Using a nonzero B<M_CHECK_ACTION> value can be useful because otherwise a "
-"crash may happen much later, and the true cause of the problem is then very "
-"hard to track down."
+"On success, B<malloc_set_state>() returns 0. If the implementation detects "
+"that I<state> does not point to a correctly formed data structure, "
+"B<malloc_set_state>() returns -1. If the implementation detects that the "
+"version of the data structure referred to by I<state> is a more recent "
+"version than this implementation knows about, B<malloc_set_state>() returns "
+"-2."
msgstr ""
-#. type: TP
-#: build/C/man3/mallopt.3:119
-#, no-wrap
-msgid "B<M_MMAP_MAX>"
+#. type: Plain text
+#: build/C/man3/malloc_get_state.3:88 build/C/man3/malloc_hook.3:82 build/C/man3/mcheck.3:147 build/C/man3/mtrace.3:80
+msgid "These functions are GNU extensions."
msgstr ""
-#. The following text adapted from comments in the glibc source:
#. type: Plain text
-#: build/C/man3/mallopt.3:129
+#: build/C/man3/malloc_get_state.3:94
msgid ""
-"This parameter specifies the maximum number of allocation requests that may "
-"be simultaneously serviced using B<mmap>(2). This parameter exists because "
-"some systems have a limited number of internal tables for use by B<mmap>(2), "
-"and using more than a few of them may degrade performance."
+"These functions are useful when using this B<malloc>(3) implementation as "
+"part of a shared library, and the heap contents are saved/restored via some "
+"other method. This technique is used by GNU Emacs to implement its "
+"\"dumping\" function."
msgstr ""
+#. i.e., calls __malloc_check_init()
+#. i.e., malloc checking is not already in use
+#. and the caller requested malloc checking
#. type: Plain text
-#: build/C/man3/mallopt.3:136
+#: build/C/man3/malloc_get_state.3:111
msgid ""
-"The default value is 65,536, a value which has no special significance and "
-"which servers only as a safeguard. Setting this parameter to 0 disables the "
-"use of B<mmap>(2) for servicing large allocation requests."
+"Hook function pointers are never saved or restored by these functions, with "
+"two exceptions: if malloc checking (see B<mallopt>(3)) was in use when "
+"B<malloc_get_state>() was called, then B<malloc_set_state>() resets malloc "
+"checking hooks if possible; if malloc checking was not in use in the "
+"recorded state, but the caller has requested malloc checking, then the hooks "
+"are reset to 0."
msgstr ""
-#. type: TP
-#: build/C/man3/mallopt.3:136
+#. type: Plain text
+#: build/C/man3/malloc_get_state.3:114
+msgid "B<malloc>(3), B<mallopt>(3)"
+msgstr ""
+
+#. type: TH
+#: build/C/man3/malloc_hook.3:10
#, no-wrap
-msgid "B<M_MMAP_THRESHOLD>"
+msgid "MALLOC_HOOK"
+msgstr ""
+
+#. type: TH
+#: build/C/man3/malloc_hook.3:10
+#, no-wrap
+msgid "2010-10-13"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:145
+#: build/C/man3/malloc_hook.3:15
msgid ""
-"For allocations greater than or equal to the limit specified (in bytes) by "
-"B<M_MMAP_THRESHOLD> that can't be satisfied from the free list, the "
-"memory-allocation functions employ B<mmap>(2) instead of increasing the "
-"program break using B<sbrk>(2)."
+"__malloc_hook, __malloc_initialize_hook, __memalign_hook, __free_hook, "
+"__realloc_hook, __after_morecore_hook - malloc debugging variables"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:165
-msgid ""
-"Allocating memory using B<mmap>(2) has the significant advantage that the "
-"allocated memory blocks can always be independently released back to the "
-"system. (By contrast, the heap can be trimmed only if memory is freed at "
-"the top end.) On the other hand, there are some disadvantages to the use of "
-"B<mmap>(2): deallocated space is not placed on the free list for reuse by "
-"later allocations; memory may be wasted because B<mmap>(2) allocations must "
-"be page-aligned; and the kernel must perform the expensive task of zeroing "
-"out memory allocated via B<mmap>(2). Balancing these factors leads to a "
-"default setting of 128*1024 for the B<M_MMAP_THRESHOLD> parameter."
+#: build/C/man3/malloc_hook.3:20
+#, no-wrap
+msgid "B<void *(*__malloc_hook)(size_t >I<size>B<, const void *>I<caller>B<);>\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:172
+#: build/C/man3/malloc_hook.3:23
+#, no-wrap
msgid ""
-"The lower limit for this parameter is 0. The upper limit is "
-"B<DEFAULT_MMAP_THRESHOLD_MAX>: 512*1024 on 32-bit systems or "
-"I<4*1024*1024*sizeof(long)> on 64-bit systems."
+"B<void *(*__realloc_hook)(void *>I<ptr>B<, size_t >I<size>B<, const void "
+"*>I<caller>B<);>\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:190
+#: build/C/man3/malloc_hook.3:26
+#, no-wrap
msgid ""
-"I<Note:> Nowadays, glibc uses a dynamic mmap threshold by default. The "
-"initial value of the threshold is 128*1024, but when blocks larger than the "
-"current threshold and less than or equal to B<DEFAULT_MMAP_THRESHOLD_MAX> "
-"are freed, the threshold is adjusted upwards to the size of the freed "
-"block. When dynamic mmap thresholding is in effect, the threshold for "
-"trimming the heap is also dynamically adjusted to be twice the dynamic mmap "
-"threshold. Dynamic adjustment of the mmap threshold is disabled if any of "
-"the B<M_TRIM_THRESHOLD>, B<M_TOP_PAD>, B<M_MMAP_THRESHOLD>, or B<M_MMAP_MAX> "
-"parameters is set."
+"B<void *(*__memalign_hook)(size_t >I<alignment>B<, size_t >I<size>B<,>\n"
+"B< const void *>I<caller>B<);>\n"
msgstr ""
-#. type: TP
-#: build/C/man3/mallopt.3:190
+#. type: Plain text
+#: build/C/man3/malloc_hook.3:28
#, no-wrap
-msgid "B<M_MXFAST> (since glibc 2.3)"
+msgid "B<void (*__free_hook)(void *>I<ptr>B<, const void *>I<caller>B<);>\n"
msgstr ""
-#. The following text adapted from comments in the glibc sources:
#. type: Plain text
-#: build/C/man3/mallopt.3:210
-msgid ""
-"Set the upper limit for memory allocation requests that are satisfied using "
-"\"fastbins\". (The measurement unit for this parameter is bytes.) Fastbins "
-"are storage areas that hold deallocated blocks of memory of the same size "
-"without merging adjacent free blocks. Subsequent reallocation of blocks of "
-"the same size can be handled very quickly by allocating from the fastbin, "
-"although memory fragmentation and the overall memory footprint of the "
-"program can increase. The default value for this parameter is "
-"I<64*sizeof(size_t)/4> (i.e., 64 on 32-bit architectures). The range for "
-"this parameter is 0 to I<80*sizeof(size_t)/4>. Setting B<M_MXFAST> to 0 "
-"disables the use of fastbins."
+#: build/C/man3/malloc_hook.3:30
+#, no-wrap
+msgid "B<void (*__malloc_initialize_hook)(void);>\n"
msgstr ""
-#. type: TP
-#: build/C/man3/mallopt.3:210
+#. type: Plain text
+#: build/C/man3/malloc_hook.3:32
#, no-wrap
-msgid "B<M_PERTURB> (since glibc 2.4)"
+msgid "B<void (*__after_morecore_hook)(void);>\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:225
+#: build/C/man3/malloc_hook.3:43
msgid ""
-"If this parameter is set to a nonzero value, then bytes of allocated memory "
-"(other than allocations via B<calloc>(3)) are initialized to the complement "
-"of the value in the least significant byte of I<value>, and when allocated "
-"memory is released using B<free>(3), the freed bytes are set to the least "
-"significant byte of I<value>. This can be useful for detecting errors where "
-"programs incorrectly rely on allocated memory being initialized to zero, or "
-"reuse values in memory that has already been freed."
+"The GNU C library lets you modify the behavior of B<malloc>(3), "
+"B<realloc>(3), and B<free>(3) by specifying appropriate hook functions. "
+"You can use these hooks to help you debug programs that use dynamic memory "
+"allocation, for example."
msgstr ""
-#. type: TP
-#: build/C/man3/mallopt.3:225
-#, no-wrap
-msgid "B<M_TOP_PAD>"
+#. type: Plain text
+#: build/C/man3/malloc_hook.3:50
+msgid ""
+"The variable B<__malloc_initialize_hook> points at a function that is called "
+"once when the malloc implementation is initialized. This is a weak "
+"variable, so it can be overridden in the application with a definition like "
+"the following:"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:232
-msgid ""
-"This parameter defines the amount of padding to employ when calling "
-"B<sbrk>(2) to modify the program break. (The measurement unit for this "
-"parameter is bytes.) This parameter has an effect in the following "
-"circumstances:"
+#: build/C/man3/malloc_hook.3:53
+#, no-wrap
+msgid " void (*__malloc_initialize_hook)(void) = my_init_hook;\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:239
-msgid ""
-"When the program break is increased, then B<M_TOP_PAD> bytes are added to "
-"the B<sbrk>(2) request."
+#: build/C/man3/malloc_hook.3:58
+msgid "Now the function I<my_init_hook>() can do the initialization of all hooks."
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:245
+#: build/C/man3/malloc_hook.3:74
msgid ""
-"When the heap is trimmed as a consequence of calling B<free>(3) (see the "
-"discussion of B<M_TRIM_THRESHOLD>) this much free space is preserved at the "
-"top of the heap."
+"The four functions pointed to by B<__malloc_hook>, B<__realloc_hook>, "
+"B<__memalign_hook>, B<__free_hook> have a prototype like the functions "
+"B<malloc>(3), B<realloc>(3), B<memalign>(3), B<free>(3), respectively, "
+"except that they have a final argument I<caller> that gives the address of "
+"the caller of B<malloc>(3), etc."
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:249
+#: build/C/man3/malloc_hook.3:80
msgid ""
-"In either case, the amount of padding is always rounded to a system page "
-"boundary."
+"The variable B<__after_morecore_hook> points at a function that is called "
+"each time after B<sbrk>(2) was asked for more memory."
msgstr ""
+#. https://bugzilla.redhat.com/show_bug.cgi?id=450187
+#. http://sourceware.org/bugzilla/show_bug.cgi?id=9957
#. type: Plain text
-#: build/C/man3/mallopt.3:256
+#: build/C/man3/malloc_hook.3:89
msgid ""
-"Modifying B<M_TOP_PAD> is a trade-off between increasing the number of "
-"system calls (when the parameter is set low) and wasting unused memory at "
-"the top of the heap (when the parameter is set high)."
+"The use of these hook functions is not safe in multithreaded programs, and "
+"they are now deprecated. Programmers should instead preempt calls to the "
+"relevant functions by defining and exporting functions such as \"malloc\" "
+"and \"free\"."
msgstr ""
-#. DEFAULT_TOP_PAD in glibc source
#. type: Plain text
-#: build/C/man3/mallopt.3:259
-msgid "The default value for this parameter is 128*1024."
+#: build/C/man3/malloc_hook.3:91
+msgid "Here is a short example of how to use these variables."
msgstr ""
-#. type: TP
-#: build/C/man3/mallopt.3:259
+#. type: Plain text
+#: build/C/man3/malloc_hook.3:95
#, no-wrap
-msgid "B<M_TRIM_THRESHOLD>"
+msgid ""
+"#include E<lt>stdio.hE<gt>\n"
+"#include E<lt>malloc.hE<gt>\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:275
+#: build/C/man3/malloc_hook.3:99
+#, no-wrap
msgid ""
-"When the amount of contiguous free memory at the top of the heap grows "
-"sufficiently large, B<free>(3) employs B<sbrk>(2) to release this memory "
-"back to the system. (This can be useful in programs that continue to "
-"execute for a long period after freeing a significant amount of memory.) "
-"The B<M_TRIM_THRESHOLD> parameter specifies the minimum size (in bytes) that "
-"this block of memory must reach before B<sbrk>(2) is used to trim the heap."
+"/* Prototypes for our hooks. */\n"
+"static void my_init_hook(void);\n"
+"static void *my_malloc_hook(size_t, const void *);\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:280
+#: build/C/man3/malloc_hook.3:102
+#, no-wrap
msgid ""
-"The default value for this parameter is 128*1024. Setting "
-"B<M_TRIM_THRESHOLD> to -1 disables trimming completely."
+"/* Variables to save original hooks. */\n"
+"static void *(*old_malloc_hook)(size_t, const void *);\n"
msgstr ""
-#. FIXME Do the arena parameters need to be documented?
-#. .TP
-#. .BR M_ARENA_TEST " (since glibc 2.10)"
-#. .TP
-#. .BR M_ARENA_MAX " (since glibc 2.10)"
-#
-#. Environment variables
-#. MALLOC_ARENA_MAX_
-#. MALLOC_ARENA_TEST_
-#
-#. http://udrepper.livejournal.com/20948.html describes some details
-#. of the MALLOC_ARENA_* environment variables.
-#
-#. These macros aren't enabled in production releases until 2.15?
-#. (see glibc malloc/Makefile)
#. type: Plain text
-#: build/C/man3/mallopt.3:303
+#: build/C/man3/malloc_hook.3:105
+#, no-wrap
msgid ""
-"Modifying B<M_TRIM_THRESHOLD> is a trade-off between increasing the number "
-"of system calls (when the parameter is set low) and wasting unused memory "
-"at the top of the heap (when the parameter is set high)."
+"/* Override initializing hook from the C library. */\n"
+"void (*__malloc_initialize_hook) (void) = my_init_hook;\n"
msgstr ""
-#. type: SS
-#: build/C/man3/mallopt.3:303
+#. type: Plain text
+#: build/C/man3/malloc_hook.3:112
#, no-wrap
-msgid "Environment Variables"
+msgid ""
+"static void\n"
+"my_init_hook(void)\n"
+"{\n"
+" old_malloc_hook = __malloc_hook;\n"
+" __malloc_hook = my_malloc_hook;\n"
+"}\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:318
+#: build/C/man3/malloc_hook.3:117
+#, no-wrap
msgid ""
-"A number of environment variables can be defined to modify some of the same "
-"parameters as are controlled by B<mallopt>(). Using these variables has the "
-"advantage that the source code of the program need not be changed. To be "
-"effective, these variables must be defined before the first call to a "
-"memory-allocation function. (If the same parameters are adjusted via "
-"B<mallopt>() then the B<mallopt>() settings take precedence.) For "
-"security reasons, these variables are ignored in set-user-ID and "
-"set-group-ID programs."
+"static void *\n"
+"my_malloc_hook(size_t size, const void *caller)\n"
+"{\n"
+" void *result;\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:321
+#: build/C/man3/malloc_hook.3:120
+#, no-wrap
msgid ""
-"The environment variables are as follows (note the trailing underscore at "
-"the end of the name of each variable):"
+" /* Restore all old hooks */\n"
+" __malloc_hook = old_malloc_hook;\n"
msgstr ""
-#. type: TP
-#: build/C/man3/mallopt.3:321
+#. type: Plain text
+#: build/C/man3/malloc_hook.3:123
#, no-wrap
-msgid "B<MALLOC_CHECK_>"
+msgid ""
+" /* Call recursively */\n"
+" result = malloc(size);\n"
msgstr ""
-#. On glibc 2.12/x86, a simple malloc()+free() loop is about 70% slower
-#. when MALLOC_CHECK_ was set.
#. type: Plain text
-#: build/C/man3/mallopt.3:338
+#: build/C/man3/malloc_hook.3:126
+#, no-wrap
msgid ""
-"This environment variable controls the same parameter as B<mallopt>() "
-"B<M_CHECK_ACTION>. If this variable is set to a nonzero value, then a "
-"special implementation of the memory-allocation functions is used. (This is "
-"accomplished using the B<malloc_hook>(3) feature.) This implementation "
-"performs additional error checking, but is slower than the standard set of "
-"memory-allocation functions. (This implementation does not detect all "
-"possible errors; memory leaks can still occur.)"
+" /* Save underlying hooks */\n"
+" old_malloc_hook = __malloc_hook;\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:343
+#: build/C/man3/malloc_hook.3:130
+#, no-wrap
msgid ""
-"The value assigned to this environment variable should be a single digit, "
-"whose meaning is as described for B<M_CHECK_ACTION>. Any characters beyond "
-"the initial digit are ignored."
+" /* printf() might call malloc(), so protect it too. */\n"
+" printf(\"malloc(%u) called from %p returns %p\\en\",\n"
+" (unsigned int) size, caller, result);\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:352
+#: build/C/man3/malloc_hook.3:133
+#, no-wrap
msgid ""
-"For security reasons, the effect of B<MALLOC_CHECK_> is disabled by default "
-"for set-user-ID and set-group-ID programs. However, if the file "
-"I</etc/suid-debug> exists (the content of the file is irrelevant), then "
-"B<MALLOC_CHECK_> also has an effect for set-user-ID and set-group-ID "
-"programs."
+" /* Restore our own hooks */\n"
+" __malloc_hook = my_malloc_hook;\n"
msgstr ""
-#. type: TP
-#: build/C/man3/mallopt.3:352
+#. type: Plain text
+#: build/C/man3/malloc_hook.3:136
#, no-wrap
-msgid "B<MALLOC_MMAP_MAX_>"
+msgid ""
+" return result;\n"
+"}\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:357
-msgid "Controls the same parameter as B<mallopt>() B<M_MMAP_MAX>."
+#: build/C/man3/malloc_hook.3:142
+msgid "B<mallinfo>(3), B<malloc>(3), B<mcheck>(3), B<mtrace>(3)"
msgstr ""
-#. type: TP
-#: build/C/man3/mallopt.3:357
+#. type: TH
+#: build/C/man3/malloc_info.3:25
#, no-wrap
-msgid "B<MALLOC_MMAP_THRESHOLD_>"
+msgid "MALLOC_INFO"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:362
-msgid "Controls the same parameter as B<mallopt>() B<M_MMAP_THRESHOLD>."
+#: build/C/man3/malloc_info.3:28
+msgid "malloc_info - export malloc state to a stream"
msgstr ""
-#. type: TP
-#: build/C/man3/mallopt.3:362
+#. type: Plain text
+#: build/C/man3/malloc_info.3:33
#, no-wrap
-msgid "B<MALLOC_PERTURB_>"
+msgid "B<int malloc_info(int >I<options>B<, FILE *>I<stream>B<);>\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:367
-msgid "Controls the same parameter as B<mallopt>() B<M_PERTURB>."
-msgstr ""
-
-#. type: TP
-#: build/C/man3/mallopt.3:367
-#, no-wrap
-msgid "B<MALLOC_TRIM_THRESHOLD_>"
+#: build/C/man3/malloc_info.3:44
+msgid ""
+"The B<malloc_info>() function exports an XML string that describes the "
+"current state of the memory-allocation implementation in the caller. The "
+"string is printed on the file stream I<stream>. The exported string "
+"includes information about all arenas (see B<malloc>(3))."
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:372
-msgid "Controls the same parameter as B<mallopt>() B<M_TRIM_THRESHOLD>."
+#: build/C/man3/malloc_info.3:48
+msgid "As currently implemented, I<options> must be zero."
msgstr ""
-#. type: TP
-#: build/C/man3/mallopt.3:372
-#, no-wrap
-msgid "B<MALLOC_TOP_PAD_>"
+#. type: Plain text
+#: build/C/man3/malloc_info.3:55
+msgid ""
+"On success, B<malloc_info>() returns 0; on error, it returns -1, with "
+"I<errno> set to indicate the cause."
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:377
-msgid "Controls the same parameter as B<mallopt>() B<M_TOP_PAD>."
+#: build/C/man3/malloc_info.3:60
+msgid "I<options> was nonzero."
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:382
-msgid "On success, B<mallopt>() returns 1. On error, it returns 0."
+#: build/C/man3/malloc_info.3:63
+msgid "B<malloc_info>() was added to glibc in version 2.10."
msgstr ""
-#. .SH VERSIONS
-#. Available already in glibc 2.0, possibly earlier
#. type: Plain text
-#: build/C/man3/mallopt.3:390
-msgid "On error, I<errno> is I<not> set."
+#: build/C/man3/malloc_info.3:65 build/C/man3/malloc_stats.3:57 build/C/man3/malloc_trim.3:62 build/C/man3/malloc_usable_size.3:55
+msgid "This function is a GNU extension."
msgstr ""
-#. .SH NOTES
#. type: Plain text
-#: build/C/man3/mallopt.3:404
+#: build/C/man3/malloc_info.3:71
msgid ""
-"This function is not specified by POSIX or the C standards. A similar "
-"function exists on many System V derivatives, but the range of values for "
-"I<param> varies across systems. The SVID defined options B<M_MXFAST>, "
-"B<M_NLBLKS>, B<M_GRAIN>, and B<M_KEEP>, but only the first of these is "
-"implemented in glibc."
+"The memory-allocation information is provided as an XML string (rather than "
+"a C structure) because the information may change over time (according to "
+"changes in the underlying implementation). The output XML string includes a "
+"version field."
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:408
-msgid "Specifying an invalid value for I<param> does not generate an error."
+#: build/C/man3/malloc_info.3:77
+msgid ""
+"The B<open_memstream>(3) function can be used to send the output of "
+"B<malloc_info>() directly into a buffer in memory, rather than to a file."
msgstr ""
-#. FIXME This looks buggy:
-#. setting the M_MXFAST limit rounds up: (s + SIZE_SZ) & ~MALLOC_ALIGN_MASK)
-#. malloc requests are rounded up:
-#. (req) + SIZE_SZ + MALLOC_ALIGN_MASK) & ~MALLOC_ALIGN_MASK
-#. http://sources.redhat.com/bugzilla/show_bug.cgi?id=12129
#. type: Plain text
-#: build/C/man3/mallopt.3:416
+#: build/C/man3/malloc_info.3:84
msgid ""
-"A calculation error within the glibc implementation means that a call of the "
-"form:"
+"The B<malloc_info>() function is designed to address deficiencies in "
+"B<malloc_stats>(3) and B<mallinfo>(3)."
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:419
-#, no-wrap
-msgid " mallopt(M_MXFAST, n)\n"
+#: build/C/man3/malloc_info.3:95
+msgid ""
+"The program below takes up to four command-line arguments, of which the "
+"first three are mandatory. The first argument specifies the number of "
+"threads that the program should create. All of the threads, including the "
+"main thread, allocate the number of blocks of memory specified by the second "
+"argument. The third argument controls the size of the blocks to be "
+"allocated. The main thread creates blocks of this size, the second thread "
+"created by the program allocates blocks of twice this size, the third thread "
+"allocates blocks of three times this size, and so on."
msgstr ""
-#. Bins are multiples of 2 * sizeof(size_t) + sizeof(size_t)
#. type: Plain text
-#: build/C/man3/mallopt.3:431
+#: build/C/man3/malloc_info.3:102
msgid ""
-"does not result in fastbins being employed for all allocations of size up to "
-"I<n>. To ensure desired results, I<n> should be rounded up to the next "
-"multiple greater than or equal to I<(2k+1)*sizeof(size_t)>, where I<k> is an "
-"integer."
+"The program calls B<malloc_info>() twice to display the memory-allocation "
+"state. The first call takes place before any threads are created or memory "
+"allocated. The second call is performed after all threads have allocated "
+"memory."
msgstr ""
-#. FIXME MALLOC_MMAP_THRESHOLD_ and MALLOC_MMAP_MAX_
-#. do have an effect for set-user-ID programs (but not
-#. set-group-ID programs).
-#. http://sources.redhat.com/bugzilla/show_bug.cgi?id=12155
#. type: Plain text
-#: build/C/man3/mallopt.3:443
+#: build/C/man3/malloc_info.3:110
msgid ""
-"The B<MALLOC_MMAP_THRESHOLD_> and B<MALLOC_MMAP_MAX_> variables are I<not> "
-"ignored in set-group-ID programs."
+"In the following example, the command-line arguments specify the creation of "
+"one additional thread, and both the main thread and the additional thread "
+"allocate 10000 blocks of memory. After the blocks of memory have been "
+"allocated, B<malloc_info>() shows the state of two allocation arenas."
msgstr ""
-#. FIXME http://sources.redhat.com/bugzilla/show_bug.cgi?id=12140
#. type: Plain text
-#: build/C/man3/mallopt.3:464
+#: build/C/man3/malloc_info.3:135
+#, no-wrap
msgid ""
-"If B<mallopt>() is used to set B<M_PERTURB>, then, as expected, the bytes "
-"of allocated memory are initialized to the complement of the byte in "
-"I<value>, and when that memory is freed, the bytes of the region are "
-"initialized to the byte specified in I<value>. However, there is an "
-"off-by-I<sizeof(size_t)> error in the implementation: instead of "
-"initializing precisely the block of memory being freed by the call "
-"I<free(p)>, the block starting at I<p+sizeof(size_t)> is initialized."
+"$ B<getconf GNU_LIBC_VERSION>\n"
+"glibc 2.13\n"
+"$ B<./a.out 1 10000 100>\n"
+"============ Before allocating blocks ============\n"
+"E<lt>malloc version=\"1\"E<gt>\n"
+"E<lt>heap nr=\"0\"E<gt>\n"
+"E<lt>sizesE<gt>\n"
+"E<lt>/sizesE<gt>\n"
+"E<lt>total type=\"fast\" count=\"0\" size=\"0\"/E<gt>\n"
+"E<lt>total type=\"rest\" count=\"0\" size=\"0\"/E<gt>\n"
+"E<lt>system type=\"current\" size=\"135168\"/E<gt>\n"
+"E<lt>system type=\"max\" size=\"135168\"/E<gt>\n"
+"E<lt>aspace type=\"total\" size=\"135168\"/E<gt>\n"
+"E<lt>aspace type=\"mprotect\" size=\"135168\"/E<gt>\n"
+"E<lt>/heapE<gt>\n"
+"E<lt>total type=\"fast\" count=\"0\" size=\"0\"/E<gt>\n"
+"E<lt>total type=\"rest\" count=\"0\" size=\"0\"/E<gt>\n"
+"E<lt>system type=\"current\" size=\"135168\"/E<gt>\n"
+"E<lt>system type=\"max\" size=\"135168\"/E<gt>\n"
+"E<lt>aspace type=\"total\" size=\"135168\"/E<gt>\n"
+"E<lt>aspace type=\"mprotect\" size=\"135168\"/E<gt>\n"
+"E<lt>/mallocE<gt>\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:473
+#: build/C/man3/malloc_info.3:165
+#, no-wrap
msgid ""
-"The program below demonstrates the use of B<M_CHECK_ACTION>. If the program "
-"is supplied with an (integer) command-line argument, then that argument is "
-"used to set the B<M_CHECK_ACTION> parameter. The program then allocates a "
-"block of memory, and frees it twice (an error)."
+"============ After allocating blocks ============\n"
+"E<lt>malloc version=\"1\"E<gt>\n"
+"E<lt>heap nr=\"0\"E<gt>\n"
+"E<lt>sizesE<gt>\n"
+"E<lt>/sizesE<gt>\n"
+"E<lt>total type=\"fast\" count=\"0\" size=\"0\"/E<gt>\n"
+"E<lt>total type=\"rest\" count=\"0\" size=\"0\"/E<gt>\n"
+"E<lt>system type=\"current\" size=\"1081344\"/E<gt>\n"
+"E<lt>system type=\"max\" size=\"1081344\"/E<gt>\n"
+"E<lt>aspace type=\"total\" size=\"1081344\"/E<gt>\n"
+"E<lt>aspace type=\"mprotect\" size=\"1081344\"/E<gt>\n"
+"E<lt>/heapE<gt>\n"
+"E<lt>heap nr=\"1\"E<gt>\n"
+"E<lt>sizesE<gt>\n"
+"E<lt>/sizesE<gt>\n"
+"E<lt>total type=\"fast\" count=\"0\" size=\"0\"/E<gt>\n"
+"E<lt>total type=\"rest\" count=\"0\" size=\"0\"/E<gt>\n"
+"E<lt>system type=\"current\" size=\"1032192\"/E<gt>\n"
+"E<lt>system type=\"max\" size=\"1032192\"/E<gt>\n"
+"E<lt>aspace type=\"total\" size=\"1032192\"/E<gt>\n"
+"E<lt>aspace type=\"mprotect\" size=\"1032192\"/E<gt>\n"
+"E<lt>/heapE<gt>\n"
+"E<lt>total type=\"fast\" count=\"0\" size=\"0\"/E<gt>\n"
+"E<lt>total type=\"rest\" count=\"0\" size=\"0\"/E<gt>\n"
+"E<lt>system type=\"current\" size=\"2113536\"/E<gt>\n"
+"E<lt>system type=\"max\" size=\"2113536\"/E<gt>\n"
+"E<lt>aspace type=\"total\" size=\"2113536\"/E<gt>\n"
+"E<lt>aspace type=\"mprotect\" size=\"2113536\"/E<gt>\n"
+"E<lt>/mallocE<gt>\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:477
+#: build/C/man3/malloc_info.3:175
+#, no-wrap
msgid ""
-"The following shell session shows what happens when we run this program "
-"under glibc, with the default value for B<M_CHECK_ACTION>:"
+"#include E<lt>unistd.hE<gt>\n"
+"#include E<lt>stdlib.hE<gt>\n"
+"#include E<lt>pthread.hE<gt>\n"
+"#include E<lt>malloc.hE<gt>\n"
+"#include E<lt>errno.hE<gt>\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:496
+#: build/C/man3/malloc_info.3:178
#, no-wrap
msgid ""
-"$ B<./a.out>\n"
-"*** glibc detected *** ./a.out: double free or corruption (top): 0x09d30008 "
-"***\n"
-"======= Backtrace: =========\n"
-"/lib/libc.so.6(+0x6c501)[0x523501]\n"
-"/lib/libc.so.6(+0x6dd70)[0x524d70]\n"
-"/lib/libc.so.6(cfree+0x6d)[0x527e5d]\n"
-"\\&./a.out[0x80485db]\n"
-"/lib/libc.so.6(__libc_start_main+0xe7)[0x4cdce7]\n"
-"\\&./a.out[0x8048471]\n"
-"======= Memory map: ========\n"
-"001e4000-001fe000 r-xp 00000000 08:06 1083555 /lib/libgcc_s.so.1\n"
-"001fe000-001ff000 r--p 00019000 08:06 1083555 /lib/libgcc_s.so.1\n"
-"[some lines omitted]\n"
-"b7814000-b7817000 rw-p 00000000 00:00 0\n"
-"bff53000-bff74000 rw-p 00000000 00:00 0 [stack]\n"
-"Aborted (core dumped)\n"
+"static size_t blockSize;\n"
+"static int numThreads, numBlocks;\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:501
+#: build/C/man3/malloc_info.3:181 build/C/man2/memfd_create.2:368 build/C/man2/memfd_create.2:450
+#, no-wrap
msgid ""
-"The following runs show the results when employing other values for "
-"B<M_CHECK_ACTION:>"
+"#define errExit(msg) do { perror(msg); exit(EXIT_FAILURE); \\e\n"
+" } while (0)\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:514
+#: build/C/man3/malloc_info.3:187
#, no-wrap
msgid ""
-"$ B<./a.out 1> # Diagnose error and continue\n"
-"main(): returned from first free() call\n"
-"*** glibc detected *** ./a.out: double free or corruption (top): 0x09cbe008 "
-"***\n"
-"main(): returned from second free() call\n"
-"$ B<./a.out 2> # Abort without error message\n"
-"main(): returned from first free() call\n"
-"Aborted (core dumped)\n"
-"$ B<./a.out 0> # Ignore error and continue\n"
-"main(): returned from first free() call\n"
-"main(): returned from second free() call\n"
+"static void *\n"
+"thread_func(void *arg)\n"
+"{\n"
+" int j;\n"
+" int tn = (int) arg;\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:520
+#: build/C/man3/malloc_info.3:190
+#, no-wrap
msgid ""
-"The next run shows how to set the same parameter using the B<MALLOC_CHECK_> "
-"environment variable:"
+" /* The multiplier \\(aq(2 + tn)\\(aq ensures that each thread "
+"(including\n"
+" the main thread) allocates a different amount of memory */\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:527
+#: build/C/man3/malloc_info.3:194
#, no-wrap
msgid ""
-"$ B<MALLOC_CHECK_=1 ./a.out>\n"
-"main(): returned from first free() call\n"
-"*** glibc detected *** ./a.out: free(): invalid pointer: 0x092c2008 ***\n"
-"main(): returned from second free() call\n"
-msgstr ""
-
-#. type: SS
-#: build/C/man3/mallopt.3:529 build/C/man2/mprotect.2:159
-#, no-wrap
-msgid "Program source"
+" for (j = 0; j E<lt> numBlocks; j++)\n"
+" if (malloc(blockSize * (2 + tn)) == NULL)\n"
+" errExit(\"malloc-thread\");\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:535
+#: build/C/man3/malloc_info.3:198
#, no-wrap
msgid ""
-"#include E<lt>malloc.hE<gt>\n"
-"#include E<lt>stdio.hE<gt>\n"
-"#include E<lt>stdlib.hE<gt>\n"
+" sleep(100); /* Sleep until main thread terminates */\n"
+" return NULL;\n"
+"}\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:540
+#: build/C/man3/malloc_info.3:204
#, no-wrap
msgid ""
"int\n"
"main(int argc, char *argv[])\n"
"{\n"
-" char *p;\n"
+" int j, tn, sleepTime;\n"
+" pthread_t *thr;\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:547
+#: build/C/man3/malloc_info.3:211
#, no-wrap
msgid ""
-" if (argc E<gt> 1) {\n"
-" if (argc != 2) {\n"
-" fprintf(stderr, \"%s E<lt>M_CHECK_ACTION-valueE<gt>\\en\", "
-"argv[0]);\n"
-" exit(EXIT_FAILURE);\n"
-" }\n"
+" if (argc E<lt> 4) {\n"
+" fprintf(stderr,\n"
+" \"%s num-threads num-blocks block-size [sleep-time]\\en\",\n"
+" argv[0]);\n"
+" exit(EXIT_FAILURE);\n"
" }\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:552
+#: build/C/man3/malloc_info.3:216
#, no-wrap
msgid ""
-" if (mallopt(M_CHECK_ACTION, atoi(argv[1])) != 1) {\n"
-" fprintf(stderr, \"mallopt() failed\");\n"
-" exit(EXIT_FAILURE);\n"
-" }\n"
+" numThreads = atoi(argv[1]);\n"
+" numBlocks = atoi(argv[2]);\n"
+" blockSize = atoi(argv[3]);\n"
+" sleepTime = (argc E<gt> 4) ? atoi(argv[4]) : 0;\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:558
+#: build/C/man3/malloc_info.3:220
#, no-wrap
msgid ""
-" p = malloc(1000);\n"
-" if (p == NULL) {\n"
-" fprintf(stderr, \"malloc() failed\");\n"
-" exit(EXIT_FAILURE);\n"
-" }\n"
+" thr = calloc(numThreads, sizeof(pthread_t));\n"
+" if (thr == NULL)\n"
+" errExit(\"calloc\");\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:561
+#: build/C/man3/malloc_info.3:223
#, no-wrap
msgid ""
-" free(p);\n"
-" printf(\"main(): returned from first free() call\\en\");\n"
+" printf(\"============ Before allocating blocks ============\\en\");\n"
+" malloc_info(0, stdout);\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:564
+#: build/C/man3/malloc_info.3:225
#, no-wrap
-msgid ""
-" free(p);\n"
-" printf(\"main(): returned from second free() call\\en\");\n"
+msgid " /* Create threads that allocate different amounts of memory */\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:567 build/C/man2/mmap.2:652
+#: build/C/man3/malloc_info.3:231
#, no-wrap
msgid ""
-" exit(EXIT_SUCCESS);\n"
-"}\n"
+" for (tn = 0; tn E<lt> numThreads; tn++) {\n"
+" errno = pthread_create(&thr[tn], NULL, thread_func,\n"
+" (void *) tn);\n"
+" if (errno != 0)\n"
+" errExit(\"pthread_create\");\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mallopt.3:578
-msgid ""
-"B<mmap>(2) B<sbrk>(2), B<mallinfo>(3), B<malloc>(3), B<malloc_hook>(3), "
-"B<malloc_trim>(3), B<mtrace>(3), B<posix_memalign>(3)"
-msgstr ""
-
-#. type: TH
-#: build/C/man2/mlock.2:27
+#: build/C/man3/malloc_info.3:236
#, no-wrap
-msgid "MLOCK"
+msgid ""
+" /* If we add a sleep interval after the start-up of each\n"
+" thread, the threads likely won\\(aqt contend for malloc\n"
+" mutexes, and therefore additional arenas won\\(aqt be\n"
+" allocated (see malloc(3)). */\n"
msgstr ""
-#. type: TH
-#: build/C/man2/mlock.2:27
+#. type: Plain text
+#: build/C/man3/malloc_info.3:240
#, no-wrap
-msgid "2011-09-14"
+msgid ""
+" if (sleepTime E<gt> 0)\n"
+" sleep(sleepTime);\n"
+" }\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:30
-msgid "mlock, munlock, mlockall, munlockall - lock and unlock memory"
+#: build/C/man3/malloc_info.3:242
+#, no-wrap
+msgid " /* The main thread also allocates some memory */\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:33 build/C/man2/mmap.2:46 build/C/man2/mmap2.2:35 build/C/man2/mprotect.2:38 build/C/man2/mremap.2:39
+#: build/C/man3/malloc_info.3:246
#, no-wrap
-msgid "B<#include E<lt>sys/mman.hE<gt>>\n"
+msgid ""
+" for (j = 0; j E<lt> numBlocks; j++)\n"
+" if (malloc(blockSize) == NULL)\n"
+" errExit(\"malloc\");\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:36
+#: build/C/man3/malloc_info.3:249
#, no-wrap
msgid ""
-"B<int mlock(const void *>I<addr>B<, size_t >I<len>B<);>\n"
-"B<int munlock(const void *>I<addr>B<, size_t >I<len>B<);>\n"
+" sleep(2); /* Give all threads a chance to\n"
+" complete allocations */\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:39
+#: build/C/man3/malloc_info.3:252
#, no-wrap
msgid ""
-"B<int mlockall(int >I<flags>B<);>\n"
-"B<int munlockall(void);>\n"
+" printf(\"\\en============ After allocating blocks ============\\en\");\n"
+" malloc_info(0, stdout);\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:55
+#: build/C/man3/malloc_info.3:262
msgid ""
-"B<mlock>() and B<mlockall>() respectively lock part or all of the calling "
-"process's virtual address space into RAM, preventing that memory from being "
-"paged to the swap area. B<munlock>() and B<munlockall>() perform the "
-"converse operation, respectively unlocking part or all of the calling "
-"process's virtual address space, so that pages in the specified virtual "
-"address range may once more to be swapped out if required by the kernel "
-"memory manager. Memory locking and unlocking are performed in units of "
-"whole pages."
+"B<mallinfo>(3), B<malloc>(3), B<malloc_stats>(3), B<mallopt>(3), "
+"B<open_memstream>(3)"
msgstr ""
-#. type: SS
-#: build/C/man2/mlock.2:55
+#. type: TH
+#: build/C/man3/malloc_stats.3:26
#, no-wrap
-msgid "mlock() and munlock()"
+msgid "MALLOC_STATS"
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:65
-msgid ""
-"B<mlock>() locks pages in the address range starting at I<addr> and "
-"continuing for I<len> bytes. All pages that contain a part of the specified "
-"address range are guaranteed to be resident in RAM when the call returns "
-"successfully; the pages are guaranteed to stay in RAM until later unlocked."
+#: build/C/man3/malloc_stats.3:29
+msgid "malloc_stats - print memory allocation statistics"
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:74
-msgid ""
-"B<munlock>() unlocks pages in the address range starting at I<addr> and "
-"continuing for I<len> bytes. After this call, all pages that contain a part "
-"of the specified memory range can be moved to external swap space again by "
-"the kernel."
+#: build/C/man3/malloc_stats.3:33
+msgid "B<void malloc_stats(void);>"
msgstr ""
-#. type: SS
-#: build/C/man2/mlock.2:74
-#, no-wrap
-msgid "mlockall() and munlockall()"
+#. .SH VERSIONS
+#. Available already in glibc 2.0, possibly earlier
+#. type: Plain text
+#: build/C/man3/malloc_stats.3:55
+msgid ""
+"The B<malloc_stats>() function prints (on standard error) statistics about "
+"memory allocated by B<malloc>(3) and related functions. For each arena "
+"(allocation area), this function prints the total amount of memory allocated "
+"and the total number of bytes consumed by in-use allocations. (These two "
+"values correspond to the I<arena> and I<uordblks> fields retrieved by "
+"B<mallinfo>(3).) In addition, the function prints the sum of these two "
+"statistics for all arenas, and the maximum number of blocks and bytes that "
+"were ever simultaneously allocated using B<mmap>(2)."
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:84
+#: build/C/man3/malloc_stats.3:61
msgid ""
-"B<mlockall>() locks all pages mapped into the address space of the calling "
-"process. This includes the pages of the code, data and stack segment, as "
-"well as shared libraries, user space kernel data, shared memory, and "
-"memory-mapped files. All mapped pages are guaranteed to be resident in RAM "
-"when the call returns successfully; the pages are guaranteed to stay in RAM "
-"until later unlocked."
+"More detailed information about memory allocations in the main arena can be "
+"obtained using B<mallinfo>(3)."
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:89
-msgid ""
-"The I<flags> argument is constructed as the bitwise OR of one or more of the "
-"following constants:"
+#: build/C/man3/malloc_stats.3:67
+msgid "B<mmap>(2), B<mallinfo>(3), B<malloc>(3), B<malloc_info>(3), B<mallopt>(3)"
msgstr ""
-#. type: TP
-#: build/C/man2/mlock.2:89
+#. type: TH
+#: build/C/man3/malloc_trim.3:26
#, no-wrap
-msgid "B<MCL_CURRENT>"
+msgid "MALLOC_TRIM"
msgstr ""
-#. type: Plain text
-#: build/C/man2/mlock.2:93
-msgid ""
-"Lock all pages which are currently mapped into the address space of the "
-"process."
+#. type: TH
+#: build/C/man3/malloc_trim.3:26 build/C/man2/remap_file_pages.2:28
+#, no-wrap
+msgid "2014-05-28"
msgstr ""
-#. type: TP
-#: build/C/man2/mlock.2:93
-#, no-wrap
-msgid "B<MCL_FUTURE>"
+#. type: Plain text
+#: build/C/man3/malloc_trim.3:29
+msgid "malloc_trim - release free memory from the top of the heap"
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:100
-msgid ""
-"Lock all pages which will become mapped into the address space of the "
-"process in the future. These could be for instance new pages required by a "
-"growing heap and stack as well as new memory mapped files or shared memory "
-"regions."
+#: build/C/man3/malloc_trim.3:33
+msgid "B<int malloc_trim(size_t >I<pad>B<);>"
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:113
+#: build/C/man3/malloc_trim.3:40
msgid ""
-"If B<MCL_FUTURE> has been specified, then a later system call (e.g., "
-"B<mmap>(2), B<sbrk>(2), B<malloc>(3)), may fail if it would cause the number "
-"of locked bytes to exceed the permitted maximum (see below). In the same "
-"circumstances, stack growth may likewise fail: the kernel will deny stack "
-"expansion and deliver a B<SIGSEGV> signal to the process."
+"The B<malloc_trim>() function attempts to release free memory at the top of "
+"the heap (by calling B<sbrk>(2) with a suitable argument)."
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:117
+#: build/C/man3/malloc_trim.3:51
msgid ""
-"B<munlockall>() unlocks all pages mapped into the address space of the "
-"calling process."
+"The I<pad> argument specifies the amount of free space to leave untrimmed at "
+"the top of the heap. If this argument is 0, only the minimum amount of "
+"memory is maintained at the top of the heap (i.e., one page or less). A "
+"nonzero argument can be used to maintain some trailing space at the top of "
+"the heap in order to allow future allocations to be made without having to "
+"extend the heap with B<sbrk>(2)."
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:123
+#: build/C/man3/malloc_trim.3:56
msgid ""
-"On success these system calls return 0. On error, -1 is returned, I<errno> "
-"is set appropriately, and no changes are made to any locks in the address "
-"space of the process."
+"The B<malloc_trim>() function returns 1 if memory was actually released "
+"back to the system, or 0 if it was not possible to release any memory."
msgstr ""
+#. .SH VERSIONS
+#. Available already in glibc 2.0, possibly earlier
#. type: Plain text
-#: build/C/man2/mlock.2:132
-msgid ""
-"(Linux 2.6.9 and later) the caller had a nonzero B<RLIMIT_MEMLOCK> soft "
-"resource limit, but tried to lock more memory than the limit permitted. "
-"This limit is not enforced if the process is privileged (B<CAP_IPC_LOCK>)."
+#: build/C/man3/malloc_trim.3:60
+msgid "No errors are defined."
msgstr ""
-#. In the case of mlock(), this check is somewhat buggy: it doesn't
-#. take into account whether the to-be-locked range overlaps with
-#. already locked pages. Thus, suppose we allocate
-#. (num_physpages / 4 + 1) of memory, and lock those pages once using
-#. mlock(), and then lock the *same* page range a second time.
-#. In the case, the second mlock() call will fail, since the check
-#. calculates that the process is trying to lock (num_physpages / 2 + 2)
-#. pages, which of course is not true. (MTK, Nov 04, kernel 2.4.28)
#. type: Plain text
-#: build/C/man2/mlock.2:144
+#: build/C/man3/malloc_trim.3:71
msgid ""
-"(Linux 2.4 and earlier) the calling process tried to lock more than half of "
-"RAM."
+"This function is automatically called by B<free>(3) in certain "
+"circumstances; see the discussion of B<M_TOP_PAD> and B<M_TRIM_THRESHOLD> in "
+"B<mallopt>(3)."
msgstr ""
-#. SVr4 documents an additional EAGAIN error code.
#. type: Plain text
-#: build/C/man2/mlock.2:150
+#: build/C/man3/malloc_trim.3:74
msgid ""
-"The caller is not privileged, but needs privilege (B<CAP_IPC_LOCK>) to "
-"perform the requested operation."
+"This function cannot release free memory located at places other than the "
+"top of the heap."
msgstr ""
+#. malloc/malloc.c::mTRIm():
+#. return result | (av == &main_arena ? sYSTRIm (pad, av) : 0);
#. type: Plain text
-#: build/C/man2/mlock.2:155
-msgid "For B<mlock>() and B<munlock>():"
+#: build/C/man3/malloc_trim.3:78
+msgid "This function releases only memory in the main arena."
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:158
-msgid "Some or all of the specified address range could not be locked."
+#: build/C/man3/malloc_trim.3:82
+msgid "B<sbrk>(2), B<malloc>(3), B<mallopt>(3)"
+msgstr ""
+
+#. type: TH
+#: build/C/man3/malloc_usable_size.3:25
+#, no-wrap
+msgid "MALLOC_USABLE_SIZE"
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:165
-msgid ""
-"The result of the addition I<start>+I<len> was less than I<start> (e.g., the "
-"addition may have resulted in an overflow)."
+#: build/C/man3/malloc_usable_size.3:28
+msgid "malloc_usable_size - obtain size of block of memory allocated from heap"
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:170
-msgid "(Not on Linux) I<addr> was not a multiple of the page size."
+#: build/C/man3/malloc_usable_size.3:32
+msgid "B<size_t malloc_usable_size (void *>I<ptr>B<);>"
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:174
+#: build/C/man3/malloc_usable_size.3:40
msgid ""
-"Some of the specified address range does not correspond to mapped pages in "
-"the address space of the process."
+"The B<malloc_usable_size>() function returns the number of usable bytes in "
+"the block pointed to by I<ptr>, a pointer to a block of memory allocated by "
+"B<malloc>(3) or a related function."
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:177
-msgid "For B<mlockall>():"
+#: build/C/man3/malloc_usable_size.3:48
+msgid ""
+"B<malloc_usable_size>() returns the number of usable bytes in the block of "
+"allocated memory pointed to by I<ptr>. If I<ptr> is NULL, 0 is returned."
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:180
-msgid "Unknown I<flags> were specified."
+#: build/C/man3/malloc_usable_size.3:53
+msgid "The B<malloc_usable_size>() function is thread-safe."
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:183
-msgid "For B<munlockall>():"
+#: build/C/man3/malloc_usable_size.3:65
+msgid ""
+"The value returned by B<malloc_usable_size>() may be greater than the "
+"requested size of the allocation because of alignment and minimum size "
+"constraints. Although the excess bytes can be overwritten by the "
+"application without ill effects, this is not good programming practice: the "
+"number of excess bytes in an allocation depends on the underlying "
+"implementation."
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:187
-msgid "(Linux 2.6.8 and earlier) The caller was not privileged (B<CAP_IPC_LOCK>)."
+#: build/C/man3/malloc_usable_size.3:67
+msgid "The main use of this function is for debugging and introspection."
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:189
-msgid "POSIX.1-2001, SVr4."
+#: build/C/man3/malloc_usable_size.3:69
+msgid "B<malloc>(3)"
msgstr ""
-#. type: SH
-#: build/C/man2/mlock.2:189 build/C/man2/mmap.2:487 build/C/man2/msync.2:105
+#. type: TH
+#: build/C/man3/mallopt.3:26
#, no-wrap
-msgid "AVAILABILITY"
+msgid "MALLOPT"
msgstr ""
-#. type: Plain text
-#: build/C/man2/mlock.2:201
-msgid ""
-"On POSIX systems on which B<mlock>() and B<munlock>() are available, "
-"B<_POSIX_MEMLOCK_RANGE> is defined in I<E<lt>unistd.hE<gt>> and the number "
-"of bytes in a page can be determined from the constant B<PAGESIZE> (if "
-"defined) in I<E<lt>limits.hE<gt>> or by calling I<sysconf(_SC_PAGESIZE)>."
+#. type: TH
+#: build/C/man3/mallopt.3:26 build/C/man2/shmop.2:41
+#, no-wrap
+msgid "2014-07-08"
msgstr ""
-#. POSIX.1-2001: It shall be defined to -1 or 0 or 200112L.
-#. -1: unavailable, 0: ask using sysconf().
-#. glibc defines it to 1.
#. type: Plain text
-#: build/C/man2/mlock.2:214
-msgid ""
-"On POSIX systems on which B<mlockall>() and B<munlockall>() are available, "
-"B<_POSIX_MEMLOCK> is defined in I<E<lt>unistd.hE<gt>> to a value greater "
-"than 0. (See also B<sysconf>(3).)"
+#: build/C/man3/mallopt.3:29
+msgid "mallopt - set memory allocation parameters"
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:232
-msgid ""
-"Memory locking has two main applications: real-time algorithms and "
-"high-security data processing. Real-time applications require deterministic "
-"timing, and, like scheduling, paging is one major cause of unexpected "
-"program execution delays. Real-time applications will usually also switch "
-"to a real-time scheduler with B<sched_setscheduler>(2). Cryptographic "
-"security software often handles critical bytes like passwords or secret keys "
-"as data structures. As a result of paging, these secrets could be "
-"transferred onto a persistent swap store medium, where they might be "
-"accessible to the enemy long after the security software has erased the "
-"secrets in RAM and terminated. (But be aware that the suspend mode on "
-"laptops and some desktop computers will save a copy of the system's RAM to "
-"disk, regardless of memory locks.)"
+#: build/C/man3/mallopt.3:33
+msgid "B<int mallopt(int >I<param>B<, int >I<value>B<);>"
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:245
+#: build/C/man3/mallopt.3:44
msgid ""
-"Real-time processes that are using B<mlockall>() to prevent delays on page "
-"faults should reserve enough locked stack pages before entering the "
-"time-critical section, so that no page fault can be caused by function "
-"calls. This can be achieved by calling a function that allocates a "
-"sufficiently large automatic variable (an array) and writes to the memory "
-"occupied by this array in order to touch these stack pages. This way, "
-"enough pages will be mapped for the stack and can be locked into RAM. The "
-"dummy writes ensure that not even copy-on-write page faults can occur in the "
-"critical section."
+"The B<mallopt>() function adjusts parameters that control the behavior of "
+"the memory-allocation functions (see B<malloc>(3)). The I<param> argument "
+"specifies the parameter to be modified, and I<value> specifies the new value "
+"for that parameter."
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:251
-msgid ""
-"Memory locks are not inherited by a child created via B<fork>(2) and are "
-"automatically removed (unlocked) during an B<execve>(2) or when the process "
-"terminates."
+#: build/C/man3/mallopt.3:47
+msgid "The following values can be specified for I<param>:"
msgstr ""
-#. type: Plain text
-#: build/C/man2/mlock.2:255
-msgid ""
-"The memory lock on an address range is automatically removed if the address "
-"range is unmapped via B<munmap>(2)."
+#. type: TP
+#: build/C/man3/mallopt.3:47
+#, no-wrap
+msgid "B<M_CHECK_ACTION>"
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:268
+#: build/C/man3/mallopt.3:53
msgid ""
-"Memory locks do not stack, that is, pages which have been locked several "
-"times by calls to B<mlock>() or B<mlockall>() will be unlocked by a single "
-"call to B<munlock>() for the corresponding range or by B<munlockall>(). "
-"Pages which are mapped to several locations or by several processes stay "
-"locked into RAM as long as they are locked at least at one location or by at "
-"least one process."
+"Setting this parameter controls how glibc responds when various kinds of "
+"programming errors are detected (e.g., freeing the same pointer twice). The "
+"3 least significant bits (2, 1, and 0) of the value assigned to this "
+"parameter determine the glibc behavior, as follows:"
msgstr ""
-#. type: Plain text
-#: build/C/man2/mlock.2:279
-msgid ""
-"Under Linux, B<mlock>() and B<munlock>() automatically round I<addr> down "
-"to the nearest page boundary. However, POSIX.1-2001 allows an "
-"implementation to require that I<addr> is page aligned, so portable "
-"applications should ensure this."
+#. type: TP
+#: build/C/man3/mallopt.3:54
+#, no-wrap
+msgid "Bit 0"
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:292
+#: build/C/man3/mallopt.3:64
msgid ""
-"The I<VmLck> field of the Linux-specific I</proc/PID/status> file shows how "
-"many kilobytes of memory the process with ID I<PID> has locked using "
-"B<mlock>(), B<mlockall>(), and B<mmap>(2) B<MAP_LOCKED>."
+"If this bit is set, then print a one-line message on I<stderr> that provides "
+"details about the error. The message starts with the string \"***\\ glibc "
+"detected\\ ***\", followed by the program name, the name of the "
+"memory-allocation function in which the error was detected, a brief "
+"description of the error, and the memory address where the error was "
+"detected."
msgstr ""
-#. type: SS
-#: build/C/man2/mlock.2:292
+#. type: TP
+#: build/C/man3/mallopt.3:64
#, no-wrap
-msgid "Limits and permissions"
+msgid "Bit 1"
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:299
+#: build/C/man3/mallopt.3:79
msgid ""
-"In Linux 2.6.8 and earlier, a process must be privileged (B<CAP_IPC_LOCK>) "
-"in order to lock memory and the B<RLIMIT_MEMLOCK> soft resource limit "
-"defines a limit on how much memory the process may lock."
+"If this bit is set, then, after printing any error message specified by bit "
+"0, the program is terminated by calling B<abort>(3). In glibc versions "
+"since 2.4, if bit 0 is also set, then, between printing the error message "
+"and aborting, the program also prints a stack trace in the manner of "
+"B<backtrace>(3), and prints the process's memory mapping in the style of "
+"I</proc/[pid]/maps> (see B<proc>(5))."
msgstr ""
-#. type: Plain text
-#: build/C/man2/mlock.2:305
-msgid ""
-"Since Linux 2.6.9, no limits are placed on the amount of memory that a "
-"privileged process can lock and the B<RLIMIT_MEMLOCK> soft resource limit "
-"instead defines a limit on how much memory an unprivileged process may lock."
+#. type: TP
+#: build/C/man3/mallopt.3:79
+#, no-wrap
+msgid "Bit 2 (since glibc 2.4)"
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:313
+#: build/C/man3/mallopt.3:86
msgid ""
-"In the 2.4 series Linux kernels up to and including 2.4.17, a bug caused the "
-"B<mlockall>() B<MCL_FUTURE> flag to be inherited across a B<fork>(2). This "
-"was rectified in kernel 2.4.18."
+"This bit has an effect only if bit 0 is also set. If this bit is set, then "
+"the one-line message describing the error is simplified to contain just the "
+"name of the function where the error was detected and the brief description "
+"of the error."
msgstr ""
-#. See the following LKML thread:
-#. http://marc.theaimsgroup.com/?l=linux-kernel&m=113801392825023&w=2
-#. "Rationale for RLIMIT_MEMLOCK"
-#. 23 Jan 2006
#. type: Plain text
-#: build/C/man2/mlock.2:330
-msgid ""
-"Since kernel 2.6.9, if a privileged process calls I<mlockall(MCL_FUTURE)> "
-"and later drops privileges (loses the B<CAP_IPC_LOCK> capability by, for "
-"example, setting its effective UID to a nonzero value), then subsequent "
-"memory allocations (e.g., B<mmap>(2), B<brk>(2)) will fail if the "
-"B<RLIMIT_MEMLOCK> resource limit is encountered."
+#: build/C/man3/mallopt.3:91
+msgid "The remaining bits in I<value> are ignored."
msgstr ""
#. type: Plain text
-#: build/C/man2/mlock.2:336
+#: build/C/man3/mallopt.3:95
msgid ""
-"B<mmap>(2), B<setrlimit>(2), B<shmctl>(2), B<sysconf>(3), B<proc>(5), "
-"B<capabilities>(7)"
-msgstr ""
-
-#. type: TH
-#: build/C/man2/mmap.2:40
-#, no-wrap
-msgid "MMAP"
+"Combining the above details, the following numeric values are meaningful for "
+"B<M_CHECK_ACTION>:"
msgstr ""
-#. type: TH
-#: build/C/man2/mmap.2:40 build/C/man2/mmap2.2:29
+#. type: IP
+#: build/C/man3/mallopt.3:96
#, no-wrap
-msgid "2012-04-16"
+msgid "0"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:43
-msgid "mmap, munmap - map or unmap files or devices into memory"
+#: build/C/man3/mallopt.3:98
+msgid "Ignore error conditions; continue execution (with undefined results)."
msgstr ""
-#. type: Plain text
-#: build/C/man2/mmap.2:51
+#. type: IP
+#: build/C/man3/mallopt.3:98
#, no-wrap
-msgid ""
-"B<void *mmap(void *>I<addr>B<, size_t >I<length>B<, int >I<prot>B<, int "
-">I<flags>B<,>\n"
-"B< int >I<fd>B<, off_t >I<offset>B<);>\n"
-"B<int munmap(void *>I<addr>B<, size_t >I<length>B<);>\n"
+msgid "1"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:61
-msgid ""
-"B<mmap>() creates a new mapping in the virtual address space of the calling "
-"process. The starting address for the new mapping is specified in I<addr>. "
-"The I<length> argument specifies the length of the mapping."
+#: build/C/man3/mallopt.3:100
+msgid "Print a detailed error message and continue execution."
msgstr ""
-#. Before Linux 2.6.24, the address was rounded up to the next page
-#. boundary; since 2.6.24, it is rounded down!
-#. type: Plain text
-#: build/C/man2/mmap.2:75
-msgid ""
-"If I<addr> is NULL, then the kernel chooses the address at which to create "
-"the mapping; this is the most portable method of creating a new mapping. If "
-"I<addr> is not NULL, then the kernel takes it as a hint about where to place "
-"the mapping; on Linux, the mapping will be created at a nearby page "
-"boundary. The address of the new mapping is returned as the result of the "
-"call."
+#. type: IP
+#: build/C/man3/mallopt.3:100
+#, no-wrap
+msgid "2"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:87
-msgid ""
-"The contents of a file mapping (as opposed to an anonymous mapping; see "
-"B<MAP_ANONYMOUS> below), are initialized using I<length> bytes starting at "
-"offset I<offset> in the file (or other object) referred to by the file "
-"descriptor I<fd>. I<offset> must be a multiple of the page size as returned "
-"by I<sysconf(_SC_PAGE_SIZE)>."
+#: build/C/man3/mallopt.3:102
+msgid "Abort the program."
+msgstr ""
+
+#. type: IP
+#: build/C/man3/mallopt.3:102
+#, no-wrap
+msgid "3"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:95
+#: build/C/man3/mallopt.3:105
msgid ""
-"The I<prot> argument describes the desired memory protection of the mapping "
-"(and must not conflict with the open mode of the file). It is either "
-"B<PROT_NONE> or the bitwise OR of one or more of the following flags:"
+"Print detailed error message, stack trace, and memory mappings, and abort "
+"the program."
msgstr ""
-#. type: TP
-#: build/C/man2/mmap.2:95 build/C/man2/mprotect.2:67
+#. type: IP
+#: build/C/man3/mallopt.3:105
#, no-wrap
-msgid "B<PROT_EXEC>"
+msgid "5"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:98
-msgid "Pages may be executed."
+#: build/C/man3/mallopt.3:107
+msgid "Print a simple error message and continue execution."
msgstr ""
-#. type: TP
-#: build/C/man2/mmap.2:98 build/C/man2/mprotect.2:61
+#. type: IP
+#: build/C/man3/mallopt.3:107
#, no-wrap
-msgid "B<PROT_READ>"
+msgid "7"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:101
-msgid "Pages may be read."
+#: build/C/man3/mallopt.3:110
+msgid ""
+"Print simple error message, stack trace, and memory mappings, and abort the "
+"program."
msgstr ""
-#. type: TP
-#: build/C/man2/mmap.2:101 build/C/man2/mprotect.2:64
-#, no-wrap
-msgid "B<PROT_WRITE>"
+#. type: Plain text
+#: build/C/man3/mallopt.3:116
+msgid ""
+"Since glibc 2.3.4, the default value for the B<M_CHECK_ACTION> parameter is "
+"3. In glibc version 2.3.3 and earlier, the default value is 1."
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:104
-msgid "Pages may be written."
+#: build/C/man3/mallopt.3:121
+msgid ""
+"Using a nonzero B<M_CHECK_ACTION> value can be useful because otherwise a "
+"crash may happen much later, and the true cause of the problem is then very "
+"hard to track down."
msgstr ""
#. type: TP
-#: build/C/man2/mmap.2:104 build/C/man2/mprotect.2:58
+#: build/C/man3/mallopt.3:121
#, no-wrap
-msgid "B<PROT_NONE>"
+msgid "B<M_MMAP_MAX>"
msgstr ""
+#. The following text adapted from comments in the glibc source:
#. type: Plain text
-#: build/C/man2/mmap.2:107
-msgid "Pages may not be accessed."
+#: build/C/man3/mallopt.3:131
+msgid ""
+"This parameter specifies the maximum number of allocation requests that may "
+"be simultaneously serviced using B<mmap>(2). This parameter exists because "
+"some systems have a limited number of internal tables for use by B<mmap>(2), "
+"and using more than a few of them may degrade performance."
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:116
+#: build/C/man3/mallopt.3:138
msgid ""
-"The I<flags> argument determines whether updates to the mapping are visible "
-"to other processes mapping the same region, and whether updates are carried "
-"through to the underlying file. This behavior is determined by including "
-"exactly one of the following values in I<flags>:"
+"The default value is 65,536, a value which has no special significance and "
+"which servers only as a safeguard. Setting this parameter to 0 disables the "
+"use of B<mmap>(2) for servicing large allocation requests."
msgstr ""
#. type: TP
-#: build/C/man2/mmap.2:116
+#: build/C/man3/mallopt.3:138
#, no-wrap
-msgid "B<MAP_SHARED>"
+msgid "B<M_MMAP_THRESHOLD>"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:126
+#: build/C/man3/mallopt.3:147
msgid ""
-"Share this mapping. Updates to the mapping are visible to other processes "
-"that map this file, and are carried through to the underlying file. The "
-"file may not actually be updated until B<msync>(2) or B<munmap>() is "
-"called."
-msgstr ""
-
-#. type: TP
-#: build/C/man2/mmap.2:126
-#, no-wrap
-msgid "B<MAP_PRIVATE>"
+"For allocations greater than or equal to the limit specified (in bytes) by "
+"B<M_MMAP_THRESHOLD> that can't be satisfied from the free list, the "
+"memory-allocation functions employ B<mmap>(2) instead of increasing the "
+"program break using B<sbrk>(2)."
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:135
+#: build/C/man3/mallopt.3:167
msgid ""
-"Create a private copy-on-write mapping. Updates to the mapping are not "
-"visible to other processes mapping the same file, and are not carried "
-"through to the underlying file. It is unspecified whether changes made to "
-"the file after the B<mmap>() call are visible in the mapped region."
+"Allocating memory using B<mmap>(2) has the significant advantage that the "
+"allocated memory blocks can always be independently released back to the "
+"system. (By contrast, the heap can be trimmed only if memory is freed at "
+"the top end.) On the other hand, there are some disadvantages to the use of "
+"B<mmap>(2): deallocated space is not placed on the free list for reuse by "
+"later allocations; memory may be wasted because B<mmap>(2) allocations must "
+"be page-aligned; and the kernel must perform the expensive task of zeroing "
+"out memory allocated via B<mmap>(2). Balancing these factors leads to a "
+"default setting of 128*1024 for the B<M_MMAP_THRESHOLD> parameter."
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:137
-msgid "Both of these flags are described in POSIX.1-2001."
+#: build/C/man3/mallopt.3:174
+msgid ""
+"The lower limit for this parameter is 0. The upper limit is "
+"B<DEFAULT_MMAP_THRESHOLD_MAX>: 512*1024 on 32-bit systems or "
+"I<4*1024*1024*sizeof(long)> on 64-bit systems."
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:140
-msgid "In addition, zero or more of the following values can be ORed in I<flags>:"
+#: build/C/man3/mallopt.3:192
+msgid ""
+"I<Note:> Nowadays, glibc uses a dynamic mmap threshold by default. The "
+"initial value of the threshold is 128*1024, but when blocks larger than the "
+"current threshold and less than or equal to B<DEFAULT_MMAP_THRESHOLD_MAX> "
+"are freed, the threshold is adjusted upward to the size of the freed block. "
+"When dynamic mmap thresholding is in effect, the threshold for trimming the "
+"heap is also dynamically adjusted to be twice the dynamic mmap threshold. "
+"Dynamic adjustment of the mmap threshold is disabled if any of the "
+"B<M_TRIM_THRESHOLD>, B<M_TOP_PAD>, B<M_MMAP_THRESHOLD>, or B<M_MMAP_MAX> "
+"parameters is set."
msgstr ""
#. type: TP
-#: build/C/man2/mmap.2:140
+#: build/C/man3/mallopt.3:192
#, no-wrap
-msgid "B<MAP_32BIT> (since Linux 2.4.20, 2.6)"
+msgid "B<M_MXFAST> (since glibc 2.3)"
msgstr ""
-#. See http://lwn.net/Articles/294642 "Tangled up in threads", 19 Aug 08
+#. The following text adapted from comments in the glibc sources:
#. type: Plain text
-#: build/C/man2/mmap.2:156
+#: build/C/man3/mallopt.3:212
msgid ""
-"Put the mapping into the first 2 Gigabytes of the process address space. "
-"This flag is only supported on x86-64, for 64-bit programs. It was added to "
-"allow thread stacks to be allocated somewhere in the first 2GB of memory, so "
-"as to improve context-switch performance on some early 64-bit processors. "
-"Modern x86-64 processors no longer have this performance problem, so use of "
-"this flag is not required on those systems. The B<MAP_32BIT> flag is "
-"ignored when B<MAP_FIXED> is set."
+"Set the upper limit for memory allocation requests that are satisfied using "
+"\"fastbins\". (The measurement unit for this parameter is bytes.) Fastbins "
+"are storage areas that hold deallocated blocks of memory of the same size "
+"without merging adjacent free blocks. Subsequent reallocation of blocks of "
+"the same size can be handled very quickly by allocating from the fastbin, "
+"although memory fragmentation and the overall memory footprint of the "
+"program can increase. The default value for this parameter is "
+"I<64*sizeof(size_t)/4> (i.e., 64 on 32-bit architectures). The range for "
+"this parameter is 0 to I<80*sizeof(size_t)/4>. Setting B<M_MXFAST> to 0 "
+"disables the use of fastbins."
msgstr ""
#. type: TP
-#: build/C/man2/mmap.2:156
+#: build/C/man3/mallopt.3:212
#, no-wrap
-msgid "B<MAP_ANON>"
+msgid "B<M_PERTURB> (since glibc 2.4)"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:161
-msgid "Synonym for B<MAP_ANONYMOUS>. Deprecated."
+#: build/C/man3/mallopt.3:227
+msgid ""
+"If this parameter is set to a nonzero value, then bytes of allocated memory "
+"(other than allocations via B<calloc>(3)) are initialized to the complement "
+"of the value in the least significant byte of I<value>, and when allocated "
+"memory is released using B<free>(3), the freed bytes are set to the least "
+"significant byte of I<value>. This can be useful for detecting errors where "
+"programs incorrectly rely on allocated memory being initialized to zero, or "
+"reuse values in memory that has already been freed."
msgstr ""
#. type: TP
-#: build/C/man2/mmap.2:161
+#: build/C/man3/mallopt.3:227
#, no-wrap
-msgid "B<MAP_ANONYMOUS>"
+msgid "B<M_TOP_PAD>"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:183
+#: build/C/man3/mallopt.3:234
msgid ""
-"The mapping is not backed by any file; its contents are initialized to "
-"zero. The I<fd> and I<offset> arguments are ignored; however, some "
-"implementations require I<fd> to be -1 if B<MAP_ANONYMOUS> (or B<MAP_ANON>) "
-"is specified, and portable applications should ensure this. The use of "
-"B<MAP_ANONYMOUS> in conjunction with B<MAP_SHARED> is only supported on "
-"Linux since kernel 2.4."
+"This parameter defines the amount of padding to employ when calling "
+"B<sbrk>(2) to modify the program break. (The measurement unit for this "
+"parameter is bytes.) This parameter has an effect in the following "
+"circumstances:"
msgstr ""
-#. type: TP
-#: build/C/man2/mmap.2:183
-#, no-wrap
-msgid "B<MAP_DENYWRITE>"
+#. type: Plain text
+#: build/C/man3/mallopt.3:241
+msgid ""
+"When the program break is increased, then B<M_TOP_PAD> bytes are added to "
+"the B<sbrk>(2) request."
msgstr ""
-#. Introduced in 1.1.36, removed in 1.3.24.
#. type: Plain text
-#: build/C/man2/mmap.2:191
+#: build/C/man3/mallopt.3:247
msgid ""
-"This flag is ignored. (Long ago, it signaled that attempts to write to the "
-"underlying file should fail with B<ETXTBUSY>. But this was a source of "
-"denial-of-service attacks.)"
+"When the heap is trimmed as a consequence of calling B<free>(3) (see the "
+"discussion of B<M_TRIM_THRESHOLD>) this much free space is preserved at the "
+"top of the heap."
msgstr ""
-#. type: TP
-#: build/C/man2/mmap.2:191
-#, no-wrap
-msgid "B<MAP_EXECUTABLE>"
+#. type: Plain text
+#: build/C/man3/mallopt.3:251
+msgid ""
+"In either case, the amount of padding is always rounded to a system page "
+"boundary."
msgstr ""
-#. Introduced in 1.1.38, removed in 1.3.24. Flag tested in proc_follow_link.
-#. (Long ago, it signaled that the underlying file is an executable.
-#. However, that information was not really used anywhere.)
-#. Linus talked about DOS related to MAP_EXECUTABLE, but he was thinking of
-#. MAP_DENYWRITE?
#. type: Plain text
-#: build/C/man2/mmap.2:199
-msgid "This flag is ignored."
+#: build/C/man3/mallopt.3:258
+msgid ""
+"Modifying B<M_TOP_PAD> is a trade-off between increasing the number of "
+"system calls (when the parameter is set low) and wasting unused memory at "
+"the top of the heap (when the parameter is set high)."
+msgstr ""
+
+#. DEFAULT_TOP_PAD in glibc source
+#. type: Plain text
+#: build/C/man3/mallopt.3:261
+msgid "The default value for this parameter is 128*1024."
msgstr ""
#. type: TP
-#: build/C/man2/mmap.2:199
+#: build/C/man3/mallopt.3:261
#, no-wrap
-msgid "B<MAP_FILE>"
+msgid "B<M_TRIM_THRESHOLD>"
msgstr ""
-#. On some systems, this was required as the opposite of
-#. MAP_ANONYMOUS -- mtk, 1 May 2007
#. type: Plain text
-#: build/C/man2/mmap.2:205
-msgid "Compatibility flag. Ignored."
+#: build/C/man3/mallopt.3:277
+msgid ""
+"When the amount of contiguous free memory at the top of the heap grows "
+"sufficiently large, B<free>(3) employs B<sbrk>(2) to release this memory "
+"back to the system. (This can be useful in programs that continue to "
+"execute for a long period after freeing a significant amount of memory.) "
+"The B<M_TRIM_THRESHOLD> parameter specifies the minimum size (in bytes) that "
+"this block of memory must reach before B<sbrk>(2) is used to trim the heap."
msgstr ""
-#. type: TP
-#: build/C/man2/mmap.2:205
+#. type: Plain text
+#: build/C/man3/mallopt.3:282
+msgid ""
+"The default value for this parameter is 128*1024. Setting "
+"B<M_TRIM_THRESHOLD> to -1 disables trimming completely."
+msgstr ""
+
+#. FIXME Do the arena parameters need to be documented?
+#. .TP
+#. .BR M_ARENA_TEST " (since glibc 2.10)"
+#. .TP
+#. .BR M_ARENA_MAX " (since glibc 2.10)"
+#
+#. Environment variables
+#. MALLOC_ARENA_MAX_
+#. MALLOC_ARENA_TEST_
+#
+#. http://udrepper.livejournal.com/20948.html describes some details
+#. of the MALLOC_ARENA_* environment variables.
+#
+#. These macros aren't enabled in production releases until 2.15?
+#. (see glibc malloc/Makefile)
+#. type: Plain text
+#: build/C/man3/mallopt.3:305
+msgid ""
+"Modifying B<M_TRIM_THRESHOLD> is a trade-off between increasing the number "
+"of system calls (when the parameter is set low) and wasting unused memory "
+"at the top of the heap (when the parameter is set high)."
+msgstr ""
+
+#. type: SS
+#: build/C/man3/mallopt.3:305
#, no-wrap
-msgid "B<MAP_FIXED>"
+msgid "Environment variables"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:223
+#: build/C/man3/mallopt.3:320
msgid ""
-"Don't interpret I<addr> as a hint: place the mapping at exactly that "
-"address. I<addr> must be a multiple of the page size. If the memory region "
-"specified by I<addr> and I<len> overlaps pages of any existing mapping(s), "
-"then the overlapped part of the existing mapping(s) will be discarded. If "
-"the specified address cannot be used, B<mmap>() will fail. Because "
-"requiring a fixed address for a mapping is less portable, the use of this "
-"option is discouraged."
+"A number of environment variables can be defined to modify some of the same "
+"parameters as are controlled by B<mallopt>(). Using these variables has the "
+"advantage that the source code of the program need not be changed. To be "
+"effective, these variables must be defined before the first call to a "
+"memory-allocation function. (If the same parameters are adjusted via "
+"B<mallopt>(), then the B<mallopt>() settings take precedence.) For "
+"security reasons, these variables are ignored in set-user-ID and "
+"set-group-ID programs."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mallopt.3:323
+msgid ""
+"The environment variables are as follows (note the trailing underscore at "
+"the end of the name of each variable):"
msgstr ""
#. type: TP
-#: build/C/man2/mmap.2:223
+#: build/C/man3/mallopt.3:323
#, no-wrap
-msgid "B<MAP_GROWSDOWN>"
+msgid "B<MALLOC_CHECK_>"
msgstr ""
+#. On glibc 2.12/x86, a simple malloc()+free() loop is about 70% slower
+#. when MALLOC_CHECK_ was set.
#. type: Plain text
-#: build/C/man2/mmap.2:228
+#: build/C/man3/mallopt.3:340
msgid ""
-"Used for stacks. Indicates to the kernel virtual memory system that the "
-"mapping should extend downward in memory."
+"This environment variable controls the same parameter as B<mallopt>() "
+"B<M_CHECK_ACTION>. If this variable is set to a nonzero value, then a "
+"special implementation of the memory-allocation functions is used. (This is "
+"accomplished using the B<malloc_hook>(3) feature.) This implementation "
+"performs additional error checking, but is slower than the standard set of "
+"memory-allocation functions. (This implementation does not detect all "
+"possible errors; memory leaks can still occur.)"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mallopt.3:345
+msgid ""
+"The value assigned to this environment variable should be a single digit, "
+"whose meaning is as described for B<M_CHECK_ACTION>. Any characters beyond "
+"the initial digit are ignored."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mallopt.3:354
+msgid ""
+"For security reasons, the effect of B<MALLOC_CHECK_> is disabled by default "
+"for set-user-ID and set-group-ID programs. However, if the file "
+"I</etc/suid-debug> exists (the content of the file is irrelevant), then "
+"B<MALLOC_CHECK_> also has an effect for set-user-ID and set-group-ID "
+"programs."
msgstr ""
#. type: TP
-#: build/C/man2/mmap.2:228
+#: build/C/man3/mallopt.3:354
#, no-wrap
-msgid "B<MAP_HUGETLB> (since Linux 2.6.32)"
+msgid "B<MALLOC_MMAP_MAX_>"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:234
-msgid ""
-"Allocate the mapping using \"huge pages.\" See the kernel source file "
-"I<Documentation/vm/hugetlbpage.txt> for further information."
+#: build/C/man3/mallopt.3:359
+msgid "Controls the same parameter as B<mallopt>() B<M_MMAP_MAX>."
msgstr ""
#. type: TP
-#: build/C/man2/mmap.2:234
+#: build/C/man3/mallopt.3:359
#, no-wrap
-msgid "B<MAP_LOCKED> (since Linux 2.5.37)"
+msgid "B<MALLOC_MMAP_THRESHOLD_>"
msgstr ""
-#. If set, the mapped pages will not be swapped out.
#. type: Plain text
-#: build/C/man2/mmap.2:240
-msgid ""
-"Lock the pages of the mapped region into memory in the manner of "
-"B<mlock>(2). This flag is ignored in older kernels."
+#: build/C/man3/mallopt.3:364
+msgid "Controls the same parameter as B<mallopt>() B<M_MMAP_THRESHOLD>."
msgstr ""
#. type: TP
-#: build/C/man2/mmap.2:240
+#: build/C/man3/mallopt.3:364
#, no-wrap
-msgid "B<MAP_NONBLOCK> (since Linux 2.5.46)"
+msgid "B<MALLOC_PERTURB_>"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:255
-msgid ""
-"Only meaningful in conjunction with B<MAP_POPULATE>. Don't perform "
-"read-ahead: only create page tables entries for pages that are already "
-"present in RAM. Since Linux 2.6.23, this flag causes B<MAP_POPULATE> to do "
-"nothing. One day the combination of B<MAP_POPULATE> and B<MAP_NONBLOCK> may "
-"be reimplemented."
+#: build/C/man3/mallopt.3:369
+msgid "Controls the same parameter as B<mallopt>() B<M_PERTURB>."
msgstr ""
#. type: TP
-#: build/C/man2/mmap.2:255
+#: build/C/man3/mallopt.3:369
#, no-wrap
-msgid "B<MAP_NORESERVE>"
+msgid "B<MALLOC_TRIM_THRESHOLD_>"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:270
-msgid ""
-"Do not reserve swap space for this mapping. When swap space is reserved, "
-"one has the guarantee that it is possible to modify the mapping. When swap "
-"space is not reserved one might get B<SIGSEGV> upon a write if no physical "
-"memory is available. See also the discussion of the file "
-"I</proc/sys/vm/overcommit_memory> in B<proc>(5). In kernels before 2.6, "
-"this flag only had effect for private writable mappings."
+#: build/C/man3/mallopt.3:374
+msgid "Controls the same parameter as B<mallopt>() B<M_TRIM_THRESHOLD>."
msgstr ""
#. type: TP
-#: build/C/man2/mmap.2:270
+#: build/C/man3/mallopt.3:374
#, no-wrap
-msgid "B<MAP_POPULATE> (since Linux 2.5.46)"
+msgid "B<MALLOC_TOP_PAD_>"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mallopt.3:379
+msgid "Controls the same parameter as B<mallopt>() B<M_TOP_PAD>."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mallopt.3:384
+msgid "On success, B<mallopt>() returns 1. On error, it returns 0."
+msgstr ""
+
+#. .SH VERSIONS
+#. Available already in glibc 2.0, possibly earlier
+#. type: Plain text
+#: build/C/man3/mallopt.3:392
+msgid "On error, I<errno> is I<not> set."
msgstr ""
+#. .SH NOTES
#. type: Plain text
-#: build/C/man2/mmap.2:277
+#: build/C/man3/mallopt.3:406
msgid ""
-"Populate (prefault) page tables for a mapping. For a file mapping, this "
-"causes read-ahead on the file. Later accesses to the mapping will not be "
-"blocked by page faults. B<MAP_POPULATE> is only supported for private "
-"mappings since Linux 2.6.23."
+"This function is not specified by POSIX or the C standards. A similar "
+"function exists on many System V derivatives, but the range of values for "
+"I<param> varies across systems. The SVID defined options B<M_MXFAST>, "
+"B<M_NLBLKS>, B<M_GRAIN>, and B<M_KEEP>, but only the first of these is "
+"implemented in glibc."
msgstr ""
-#. type: TP
-#: build/C/man2/mmap.2:277
+#. type: Plain text
+#: build/C/man3/mallopt.3:410
+msgid "Specifying an invalid value for I<param> does not generate an error."
+msgstr ""
+
+#. FIXME . This looks buggy:
+#. setting the M_MXFAST limit rounds up: (s + SIZE_SZ) & ~MALLOC_ALIGN_MASK)
+#. malloc requests are rounded up:
+#. (req) + SIZE_SZ + MALLOC_ALIGN_MASK) & ~MALLOC_ALIGN_MASK
+#. http://sources.redhat.com/bugzilla/show_bug.cgi?id=12129
+#. type: Plain text
+#: build/C/man3/mallopt.3:418
+msgid ""
+"A calculation error within the glibc implementation means that a call of the "
+"form:"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mallopt.3:421
#, no-wrap
-msgid "B<MAP_STACK> (since Linux 2.6.27)"
+msgid " mallopt(M_MXFAST, n)\n"
msgstr ""
-#. See http://lwn.net/Articles/294642 "Tangled up in threads", 19 Aug 08
-#. commit cd98a04a59e2f94fa64d5bf1e26498d27427d5e7
-#. http://thread.gmane.org/gmane.linux.kernel/720412
-#. "pthread_create() slow for many threads; also time to revisit 64b
-#. context switch optimization?"
+#. Bins are multiples of 2 * sizeof(size_t) + sizeof(size_t)
#. type: Plain text
-#: build/C/man2/mmap.2:290
+#: build/C/man3/mallopt.3:433
msgid ""
-"Allocate the mapping at an address suitable for a process or thread stack. "
-"This flag is currently a no-op, but is used in the glibc threading "
-"implementation so that if some architectures require special treatment for "
-"stack allocations, support can later be transparently implemented for glibc."
+"does not result in fastbins being employed for all allocations of size up to "
+"I<n>. To ensure desired results, I<n> should be rounded up to the next "
+"multiple greater than or equal to I<(2k+1)*sizeof(size_t)>, where I<k> is an "
+"integer."
msgstr ""
-#. type: TP
-#: build/C/man2/mmap.2:290
+#. FIXME . http://sources.redhat.com/bugzilla/show_bug.cgi?id=12140
+#. type: Plain text
+#: build/C/man3/mallopt.3:454
+msgid ""
+"If B<mallopt>() is used to set B<M_PERTURB>, then, as expected, the bytes "
+"of allocated memory are initialized to the complement of the byte in "
+"I<value>, and when that memory is freed, the bytes of the region are "
+"initialized to the byte specified in I<value>. However, there is an "
+"off-by-I<sizeof(size_t)> error in the implementation: instead of "
+"initializing precisely the block of memory being freed by the call "
+"I<free(p)>, the block starting at I<p+sizeof(size_t)> is initialized."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mallopt.3:463
+msgid ""
+"The program below demonstrates the use of B<M_CHECK_ACTION>. If the program "
+"is supplied with an (integer) command-line argument, then that argument is "
+"used to set the B<M_CHECK_ACTION> parameter. The program then allocates a "
+"block of memory, and frees it twice (an error)."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mallopt.3:467
+msgid ""
+"The following shell session shows what happens when we run this program "
+"under glibc, with the default value for B<M_CHECK_ACTION>:"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mallopt.3:487
#, no-wrap
-msgid "B<MAP_UNINITIALIZED> (since Linux 2.6.33)"
+msgid ""
+"$ B<./a.out>\n"
+"main(): returned from first free() call\n"
+"*** glibc detected *** ./a.out: double free or corruption (top): 0x09d30008 "
+"***\n"
+"======= Backtrace: =========\n"
+"/lib/libc.so.6(+0x6c501)[0x523501]\n"
+"/lib/libc.so.6(+0x6dd70)[0x524d70]\n"
+"/lib/libc.so.6(cfree+0x6d)[0x527e5d]\n"
+"\\&./a.out[0x80485db]\n"
+"/lib/libc.so.6(__libc_start_main+0xe7)[0x4cdce7]\n"
+"\\&./a.out[0x8048471]\n"
+"======= Memory map: ========\n"
+"001e4000-001fe000 r-xp 00000000 08:06 1083555 /lib/libgcc_s.so.1\n"
+"001fe000-001ff000 r--p 00019000 08:06 1083555 /lib/libgcc_s.so.1\n"
+"[some lines omitted]\n"
+"b7814000-b7817000 rw-p 00000000 00:00 0\n"
+"bff53000-bff74000 rw-p 00000000 00:00 0 [stack]\n"
+"Aborted (core dumped)\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:300
+#: build/C/man3/mallopt.3:492
msgid ""
-"Don't clear anonymous pages. This flag is intended to improve performance "
-"on embedded devices. This flag is only honored if the kernel was configured "
-"with the B<CONFIG_MMAP_ALLOW_UNINITIALIZED> option. Because of the security "
-"implications, that option is normally enabled only on embedded devices "
-"(i.e., devices where one has complete control of the contents of user "
-"memory)."
+"The following runs show the results when employing other values for "
+"B<M_CHECK_ACTION>:"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mallopt.3:505
+#, no-wrap
+msgid ""
+"$ B<./a.out 1> # Diagnose error and continue\n"
+"main(): returned from first free() call\n"
+"*** glibc detected *** ./a.out: double free or corruption (top): 0x09cbe008 "
+"***\n"
+"main(): returned from second free() call\n"
+"$ B<./a.out 2> # Abort without error message\n"
+"main(): returned from first free() call\n"
+"Aborted (core dumped)\n"
+"$ B<./a.out 0> # Ignore error and continue\n"
+"main(): returned from first free() call\n"
+"main(): returned from second free() call\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mallopt.3:511
+msgid ""
+"The next run shows how to set the same parameter using the B<MALLOC_CHECK_> "
+"environment variable:"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mallopt.3:518
+#, no-wrap
+msgid ""
+"$ B<MALLOC_CHECK_=1 ./a.out>\n"
+"main(): returned from first free() call\n"
+"*** glibc detected *** ./a.out: free(): invalid pointer: 0x092c2008 ***\n"
+"main(): returned from second free() call\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mallopt.3:526
+#, no-wrap
+msgid ""
+"#include E<lt>malloc.hE<gt>\n"
+"#include E<lt>stdio.hE<gt>\n"
+"#include E<lt>stdlib.hE<gt>\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mallopt.3:531 build/C/man3/mcheck.3:187
+#, no-wrap
+msgid ""
+"int\n"
+"main(int argc, char *argv[])\n"
+"{\n"
+" char *p;\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mallopt.3:538
+#, no-wrap
+msgid ""
+" if (argc E<gt> 1) {\n"
+" if (mallopt(M_CHECK_ACTION, atoi(argv[1])) != 1) {\n"
+" fprintf(stderr, \"mallopt() failed\");\n"
+" exit(EXIT_FAILURE);\n"
+" }\n"
+" }\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mallopt.3:544
+#, no-wrap
+msgid ""
+" p = malloc(1000);\n"
+" if (p == NULL) {\n"
+" fprintf(stderr, \"malloc() failed\");\n"
+" exit(EXIT_FAILURE);\n"
+" }\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mallopt.3:547
+#, no-wrap
+msgid ""
+" free(p);\n"
+" printf(\"main(): returned from first free() call\\en\");\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mallopt.3:550
+#, no-wrap
+msgid ""
+" free(p);\n"
+" printf(\"main(): returned from second free() call\\en\");\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mallopt.3:568
+msgid ""
+"B<mmap>(2), B<sbrk>(2), B<mallinfo>(3), B<malloc>(3), B<malloc_hook>(3), "
+"B<malloc_info>(3), B<malloc_stats>(3), B<malloc_trim>(3), B<mcheck>(3), "
+"B<mtrace>(3), B<posix_memalign>(3)"
+msgstr ""
+
+#. type: TH
+#: build/C/man3/mcheck.3:25
+#, no-wrap
+msgid "MCHECK"
+msgstr ""
+
+#. type: TH
+#: build/C/man3/mcheck.3:25
+#, no-wrap
+msgid "2014-01-11"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:28
+msgid ""
+"mcheck, mcheck_check_all, mcheck_pedantic, mprobe - heap consistency "
+"checking"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:31
+#, no-wrap
+msgid "B<#include E<lt>mcheck.hE<gt>>\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:33
+#, no-wrap
+msgid "B<int mcheck(void (*>I<abortfunc>B<)(enum mcheck_status >I<mstatus>B<));>\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:35
+#, no-wrap
+msgid ""
+"B<int mcheck_pedantic(void (*>I<abortfunc>B<)(enum mcheck_status "
+">I<mstatus>B<));>\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:37
+#, no-wrap
+msgid "B<void mcheck_check_all(void);>\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:39
+#, no-wrap
+msgid "B<enum mcheck_status mprobe(void *>I<ptr>B<);>\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:51
+msgid ""
+"The B<mcheck>() function installs a set of debugging hooks for the "
+"B<malloc>(3) family of memory-allocation functions. These hooks cause "
+"certain consistency checks to be performed on the state of the heap. The "
+"checks can detect application errors such as freeing a block of memory more "
+"than once or corrupting the bookkeeping data structures that immediately "
+"precede a block of allocated memory."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:63
+msgid ""
+"To be effective, the B<mcheck>() function must be called before the first "
+"call to B<malloc>(3) or a related function. In cases where this is "
+"difficult to ensure, linking the program with I<-lmcheck> inserts an "
+"implicit call to B<mcheck>() (with a NULL argument) before the first call "
+"to a memory-allocation function."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:71
+msgid ""
+"The B<mcheck_pedantic>() function is similar to B<mcheck>(), but performs "
+"checks on all allocated blocks whenever one of the memory-allocation "
+"functions is called. This can be very slow!"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:78
+msgid ""
+"The B<mcheck_check_all>() function causes an immediate check on all "
+"allocated blocks. This call is effective only if B<mcheck>() is called "
+"beforehand."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:91
+msgid ""
+"If the system detects an inconsistency in the heap, the caller-supplied "
+"function pointed to by I<abortfunc> is invoked with a single argument "
+"argument, I<mstatus>, that indicates what type of inconsistency was "
+"detected. If I<abortfunc> is NULL, a default function prints an error "
+"message on I<stderr> and calls B<abort>(3)."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:103
+msgid ""
+"The B<mprobe>() function performs a consistency check on the block of "
+"allocated memory pointed to by I<ptr>. The B<mcheck>() function should be "
+"called beforehand (otherwise B<mprobe>() returns B<MCHECK_DISABLED>)."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:111
+msgid ""
+"The following list describes the values returned by B<mprobe>() or passed "
+"as the I<mstatus> argument when I<abortfunc> is invoked:"
+msgstr ""
+
+#. type: TP
+#: build/C/man3/mcheck.3:111
+#, no-wrap
+msgid "B<MCHECK_DISABLED> (B<mprobe>() only)"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:116
+msgid ""
+"B<mcheck>() was not called before the first memory allocation function was "
+"called. Consistency checking is not possible."
+msgstr ""
+
+#. type: TP
+#: build/C/man3/mcheck.3:116
+#, no-wrap
+msgid "B<MCHECK_OK> (B<mprobe>() only)"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:119
+msgid "No inconsistency detected."
+msgstr ""
+
+#. type: TP
+#: build/C/man3/mcheck.3:119
+#, no-wrap
+msgid "B<MCHECK_HEAD>"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:122
+msgid "Memory preceding an allocated block was clobbered."
+msgstr ""
+
+#. type: TP
+#: build/C/man3/mcheck.3:122
+#, no-wrap
+msgid "B<MCHECK_TAIL>"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:125
+msgid "Memory following an allocated block was clobbered."
+msgstr ""
+
+#. type: TP
+#: build/C/man3/mcheck.3:125
+#, no-wrap
+msgid "B<MCHECK_FREE>"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:129
+msgid "A block of memory was freed twice."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:134
+msgid "B<mcheck>() and B<mcheck_pedantic>() return 0 on success, or -1 on error."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:145
+msgid ""
+"The B<mcheck_pedantic>() and B<mcheck_check_all>() functions are available "
+"since glibc 2.2. The B<mcheck>() and B<mprobe>() functions are present "
+"since at least glibc 2.0"
+msgstr ""
+
+#. But is MALLOC_CHECK_ slower?
+#. type: Plain text
+#: build/C/man3/mcheck.3:159
+msgid ""
+"Linking a program with I<-lmcheck> and using the B<MALLOC_CHECK_> "
+"environment variable (described in B<mallopt>(3)) cause the same kinds of "
+"errors to be detected. But, using B<MALLOC_CHECK_> does not require the "
+"application to be relinked."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:165
+msgid ""
+"The program below calls B<mcheck>() with a NULL argument and then frees the "
+"same block of memory twice. The following shell session demonstrates what "
+"happens when running the program:"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:170
+#, no-wrap
+msgid ""
+"$B< ./a.out>\n"
+"About to free\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:174
+#, no-wrap
+msgid ""
+"About to free a second time\n"
+"block freed twice\n"
+"Aborted (core dumped)\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:182
+#, no-wrap
+msgid ""
+"#include E<lt>stdlib.hE<gt>\n"
+"#include E<lt>stdio.hE<gt>\n"
+"#include E<lt>mcheck.hE<gt>\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:190
+#, no-wrap
+msgid ""
+" if (mcheck(NULL) != 0) {\n"
+" fprintf(stderr, \"mcheck() failed\\en\");\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:193
+#, no-wrap
+msgid ""
+" exit(EXIT_FAILURE);\n"
+" }\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:195
+#, no-wrap
+msgid " p = malloc(1000);\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:200
+#, no-wrap
+msgid ""
+" fprintf(stderr, \"About to free\\en\");\n"
+" free(p);\n"
+" fprintf(stderr, \"\\enAbout to free a second time\\en\");\n"
+" free(p);\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man3/mcheck.3:208
+msgid "B<malloc>(3), B<mallopt>(3), B<mtrace>(3)"
+msgstr ""
+
+#. type: TH
+#: build/C/man2/mlock.2:26
+#, no-wrap
+msgid "MLOCK"
+msgstr ""
+
+#. type: TH
+#: build/C/man2/mlock.2:26
+#, no-wrap
+msgid "2014-04-14"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:29
+msgid "mlock, munlock, mlockall, munlockall - lock and unlock memory"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:32 build/C/man2/mmap.2:46 build/C/man2/mmap2.2:35 build/C/man2/mprotect.2:45 build/C/man2/mremap.2:38
+#, no-wrap
+msgid "B<#include E<lt>sys/mman.hE<gt>>\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:35
+#, no-wrap
+msgid ""
+"B<int mlock(const void *>I<addr>B<, size_t >I<len>B<);>\n"
+"B<int munlock(const void *>I<addr>B<, size_t >I<len>B<);>\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:38
+#, no-wrap
+msgid ""
+"B<int mlockall(int >I<flags>B<);>\n"
+"B<int munlockall(void);>\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:54
+msgid ""
+"B<mlock>() and B<mlockall>() respectively lock part or all of the calling "
+"process's virtual address space into RAM, preventing that memory from being "
+"paged to the swap area. B<munlock>() and B<munlockall>() perform the "
+"converse operation, respectively unlocking part or all of the calling "
+"process's virtual address space, so that pages in the specified virtual "
+"address range may once more to be swapped out if required by the kernel "
+"memory manager. Memory locking and unlocking are performed in units of "
+"whole pages."
+msgstr ""
+
+#. type: SS
+#: build/C/man2/mlock.2:54
+#, no-wrap
+msgid "mlock() and munlock()"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:64
+msgid ""
+"B<mlock>() locks pages in the address range starting at I<addr> and "
+"continuing for I<len> bytes. All pages that contain a part of the specified "
+"address range are guaranteed to be resident in RAM when the call returns "
+"successfully; the pages are guaranteed to stay in RAM until later unlocked."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:73
+msgid ""
+"B<munlock>() unlocks pages in the address range starting at I<addr> and "
+"continuing for I<len> bytes. After this call, all pages that contain a part "
+"of the specified memory range can be moved to external swap space again by "
+"the kernel."
+msgstr ""
+
+#. type: SS
+#: build/C/man2/mlock.2:73
+#, no-wrap
+msgid "mlockall() and munlockall()"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:83
+msgid ""
+"B<mlockall>() locks all pages mapped into the address space of the calling "
+"process. This includes the pages of the code, data and stack segment, as "
+"well as shared libraries, user space kernel data, shared memory, and "
+"memory-mapped files. All mapped pages are guaranteed to be resident in RAM "
+"when the call returns successfully; the pages are guaranteed to stay in RAM "
+"until later unlocked."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:88
+msgid ""
+"The I<flags> argument is constructed as the bitwise OR of one or more of the "
+"following constants:"
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mlock.2:88
+#, no-wrap
+msgid "B<MCL_CURRENT>"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:92
+msgid ""
+"Lock all pages which are currently mapped into the address space of the "
+"process."
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mlock.2:92
+#, no-wrap
+msgid "B<MCL_FUTURE>"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:99
+msgid ""
+"Lock all pages which will become mapped into the address space of the "
+"process in the future. These could be for instance new pages required by a "
+"growing heap and stack as well as new memory-mapped files or shared memory "
+"regions."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:112
+msgid ""
+"If B<MCL_FUTURE> has been specified, then a later system call (e.g., "
+"B<mmap>(2), B<sbrk>(2), B<malloc>(3)), may fail if it would cause the number "
+"of locked bytes to exceed the permitted maximum (see below). In the same "
+"circumstances, stack growth may likewise fail: the kernel will deny stack "
+"expansion and deliver a B<SIGSEGV> signal to the process."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:116
+msgid ""
+"B<munlockall>() unlocks all pages mapped into the address space of the "
+"calling process."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:122
+msgid ""
+"On success these system calls return 0. On error, -1 is returned, I<errno> "
+"is set appropriately, and no changes are made to any locks in the address "
+"space of the process."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:131
+msgid ""
+"(Linux 2.6.9 and later) the caller had a nonzero B<RLIMIT_MEMLOCK> soft "
+"resource limit, but tried to lock more memory than the limit permitted. "
+"This limit is not enforced if the process is privileged (B<CAP_IPC_LOCK>)."
+msgstr ""
+
+#. In the case of mlock(), this check is somewhat buggy: it doesn't
+#. take into account whether the to-be-locked range overlaps with
+#. already locked pages. Thus, suppose we allocate
+#. (num_physpages / 4 + 1) of memory, and lock those pages once using
+#. mlock(), and then lock the *same* page range a second time.
+#. In the case, the second mlock() call will fail, since the check
+#. calculates that the process is trying to lock (num_physpages / 2 + 2)
+#. pages, which of course is not true. (MTK, Nov 04, kernel 2.4.28)
+#. type: Plain text
+#: build/C/man2/mlock.2:143
+msgid ""
+"(Linux 2.4 and earlier) the calling process tried to lock more than half of "
+"RAM."
+msgstr ""
+
+#. SVr4 documents an additional EAGAIN error code.
+#. type: Plain text
+#: build/C/man2/mlock.2:149
+msgid ""
+"The caller is not privileged, but needs privilege (B<CAP_IPC_LOCK>) to "
+"perform the requested operation."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:154
+msgid "For B<mlock>() and B<munlock>():"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:157
+msgid "Some or all of the specified address range could not be locked."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:164
+msgid ""
+"The result of the addition I<start>+I<len> was less than I<start> (e.g., the "
+"addition may have resulted in an overflow)."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:169
+msgid "(Not on Linux) I<addr> was not a multiple of the page size."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:173
+msgid ""
+"Some of the specified address range does not correspond to mapped pages in "
+"the address space of the process."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:176
+msgid "For B<mlockall>():"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:179
+msgid "Unknown I<flags> were specified."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:182
+msgid "For B<munlockall>():"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:186
+msgid "(Linux 2.6.8 and earlier) The caller was not privileged (B<CAP_IPC_LOCK>)."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:188
+msgid "POSIX.1-2001, SVr4."
+msgstr ""
+
+#. type: SH
+#: build/C/man2/mlock.2:188 build/C/man2/mmap.2:503 build/C/man2/msync.2:105
+#, no-wrap
+msgid "AVAILABILITY"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:200
+msgid ""
+"On POSIX systems on which B<mlock>() and B<munlock>() are available, "
+"B<_POSIX_MEMLOCK_RANGE> is defined in I<E<lt>unistd.hE<gt>> and the number "
+"of bytes in a page can be determined from the constant B<PAGESIZE> (if "
+"defined) in I<E<lt>limits.hE<gt>> or by calling I<sysconf(_SC_PAGESIZE)>."
+msgstr ""
+
+#. POSIX.1-2001: It shall be defined to -1 or 0 or 200112L.
+#. -1: unavailable, 0: ask using sysconf().
+#. glibc defines it to 1.
+#. type: Plain text
+#: build/C/man2/mlock.2:213
+msgid ""
+"On POSIX systems on which B<mlockall>() and B<munlockall>() are available, "
+"B<_POSIX_MEMLOCK> is defined in I<E<lt>unistd.hE<gt>> to a value greater "
+"than 0. (See also B<sysconf>(3).)"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:231
+msgid ""
+"Memory locking has two main applications: real-time algorithms and "
+"high-security data processing. Real-time applications require deterministic "
+"timing, and, like scheduling, paging is one major cause of unexpected "
+"program execution delays. Real-time applications will usually also switch "
+"to a real-time scheduler with B<sched_setscheduler>(2). Cryptographic "
+"security software often handles critical bytes like passwords or secret keys "
+"as data structures. As a result of paging, these secrets could be "
+"transferred onto a persistent swap store medium, where they might be "
+"accessible to the enemy long after the security software has erased the "
+"secrets in RAM and terminated. (But be aware that the suspend mode on "
+"laptops and some desktop computers will save a copy of the system's RAM to "
+"disk, regardless of memory locks.)"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:244
+msgid ""
+"Real-time processes that are using B<mlockall>() to prevent delays on page "
+"faults should reserve enough locked stack pages before entering the "
+"time-critical section, so that no page fault can be caused by function "
+"calls. This can be achieved by calling a function that allocates a "
+"sufficiently large automatic variable (an array) and writes to the memory "
+"occupied by this array in order to touch these stack pages. This way, "
+"enough pages will be mapped for the stack and can be locked into RAM. The "
+"dummy writes ensure that not even copy-on-write page faults can occur in the "
+"critical section."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:257
+msgid ""
+"Memory locks are not inherited by a child created via B<fork>(2) and are "
+"automatically removed (unlocked) during an B<execve>(2) or when the process "
+"terminates. The B<mlockall>() B<MCL_FUTURE> setting is not inherited by a "
+"child created via B<fork>(2) and is cleared during an B<execve>(2)."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:261
+msgid ""
+"The memory lock on an address range is automatically removed if the address "
+"range is unmapped via B<munmap>(2)."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:274
+msgid ""
+"Memory locks do not stack, that is, pages which have been locked several "
+"times by calls to B<mlock>() or B<mlockall>() will be unlocked by a single "
+"call to B<munlock>() for the corresponding range or by B<munlockall>(). "
+"Pages which are mapped to several locations or by several processes stay "
+"locked into RAM as long as they are locked at least at one location or by at "
+"least one process."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:285
+msgid ""
+"Under Linux, B<mlock>() and B<munlock>() automatically round I<addr> down "
+"to the nearest page boundary. However, POSIX.1-2001 allows an "
+"implementation to require that I<addr> is page aligned, so portable "
+"applications should ensure this."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:298
+msgid ""
+"The I<VmLck> field of the Linux-specific I</proc/PID/status> file shows how "
+"many kilobytes of memory the process with ID I<PID> has locked using "
+"B<mlock>(), B<mlockall>(), and B<mmap>(2) B<MAP_LOCKED>."
+msgstr ""
+
+#. type: SS
+#: build/C/man2/mlock.2:298
+#, no-wrap
+msgid "Limits and permissions"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:305
+msgid ""
+"In Linux 2.6.8 and earlier, a process must be privileged (B<CAP_IPC_LOCK>) "
+"in order to lock memory and the B<RLIMIT_MEMLOCK> soft resource limit "
+"defines a limit on how much memory the process may lock."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:311
+msgid ""
+"Since Linux 2.6.9, no limits are placed on the amount of memory that a "
+"privileged process can lock and the B<RLIMIT_MEMLOCK> soft resource limit "
+"instead defines a limit on how much memory an unprivileged process may lock."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:319
+msgid ""
+"In the 2.4 series Linux kernels up to and including 2.4.17, a bug caused the "
+"B<mlockall>() B<MCL_FUTURE> flag to be inherited across a B<fork>(2). This "
+"was rectified in kernel 2.4.18."
+msgstr ""
+
+#. See the following LKML thread:
+#. http://marc.theaimsgroup.com/?l=linux-kernel&m=113801392825023&w=2
+#. "Rationale for RLIMIT_MEMLOCK"
+#. 23 Jan 2006
+#. type: Plain text
+#: build/C/man2/mlock.2:336
+msgid ""
+"Since kernel 2.6.9, if a privileged process calls I<mlockall(MCL_FUTURE)> "
+"and later drops privileges (loses the B<CAP_IPC_LOCK> capability by, for "
+"example, setting its effective UID to a nonzero value), then subsequent "
+"memory allocations (e.g., B<mmap>(2), B<brk>(2)) will fail if the "
+"B<RLIMIT_MEMLOCK> resource limit is encountered."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mlock.2:343
+msgid ""
+"B<mmap>(2), B<setrlimit>(2), B<shmctl>(2), B<sysconf>(3), B<proc>(5), "
+"B<capabilities>(7)"
+msgstr ""
+
+#. type: TH
+#: build/C/man2/mmap.2:40
+#, no-wrap
+msgid "MMAP"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:43
+msgid "mmap, munmap - map or unmap files or devices into memory"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:51
+#, no-wrap
+msgid ""
+"B<void *mmap(void *>I<addr>B<, size_t >I<length>B<, int >I<prot>B<, int "
+">I<flags>B<,>\n"
+"B< int >I<fd>B<, off_t >I<offset>B<);>\n"
+"B<int munmap(void *>I<addr>B<, size_t >I<length>B<);>\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:54
+msgid "See NOTES for information on feature test macro requirements."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:63
+msgid ""
+"B<mmap>() creates a new mapping in the virtual address space of the calling "
+"process. The starting address for the new mapping is specified in I<addr>. "
+"The I<length> argument specifies the length of the mapping."
+msgstr ""
+
+#. Before Linux 2.6.24, the address was rounded up to the next page
+#. boundary; since 2.6.24, it is rounded down!
+#. type: Plain text
+#: build/C/man2/mmap.2:77
+msgid ""
+"If I<addr> is NULL, then the kernel chooses the address at which to create "
+"the mapping; this is the most portable method of creating a new mapping. If "
+"I<addr> is not NULL, then the kernel takes it as a hint about where to place "
+"the mapping; on Linux, the mapping will be created at a nearby page "
+"boundary. The address of the new mapping is returned as the result of the "
+"call."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:89
+msgid ""
+"The contents of a file mapping (as opposed to an anonymous mapping; see "
+"B<MAP_ANONYMOUS> below), are initialized using I<length> bytes starting at "
+"offset I<offset> in the file (or other object) referred to by the file "
+"descriptor I<fd>. I<offset> must be a multiple of the page size as returned "
+"by I<sysconf(_SC_PAGE_SIZE)>."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:97
+msgid ""
+"The I<prot> argument describes the desired memory protection of the mapping "
+"(and must not conflict with the open mode of the file). It is either "
+"B<PROT_NONE> or the bitwise OR of one or more of the following flags:"
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mmap.2:97 build/C/man2/mprotect.2:74
+#, no-wrap
+msgid "B<PROT_EXEC>"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:100
+msgid "Pages may be executed."
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mmap.2:100 build/C/man2/mprotect.2:68
+#, no-wrap
+msgid "B<PROT_READ>"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:103
+msgid "Pages may be read."
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mmap.2:103 build/C/man2/mprotect.2:71
+#, no-wrap
+msgid "B<PROT_WRITE>"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:106
+msgid "Pages may be written."
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mmap.2:106 build/C/man2/mprotect.2:65
+#, no-wrap
+msgid "B<PROT_NONE>"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:109
+msgid "Pages may not be accessed."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:118
+msgid ""
+"The I<flags> argument determines whether updates to the mapping are visible "
+"to other processes mapping the same region, and whether updates are carried "
+"through to the underlying file. This behavior is determined by including "
+"exactly one of the following values in I<flags>:"
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mmap.2:118
+#, no-wrap
+msgid "B<MAP_SHARED>"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:128
+msgid ""
+"Share this mapping. Updates to the mapping are visible to other processes "
+"that map this file, and are carried through to the underlying file. The "
+"file may not actually be updated until B<msync>(2) or B<munmap>() is "
+"called."
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mmap.2:128
+#, no-wrap
+msgid "B<MAP_PRIVATE>"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:137
+msgid ""
+"Create a private copy-on-write mapping. Updates to the mapping are not "
+"visible to other processes mapping the same file, and are not carried "
+"through to the underlying file. It is unspecified whether changes made to "
+"the file after the B<mmap>() call are visible in the mapped region."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:139
+msgid "Both of these flags are described in POSIX.1-2001."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:142
+msgid "In addition, zero or more of the following values can be ORed in I<flags>:"
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mmap.2:142
+#, no-wrap
+msgid "B<MAP_32BIT> (since Linux 2.4.20, 2.6)"
+msgstr ""
+
+#. See http://lwn.net/Articles/294642 "Tangled up in threads", 19 Aug 08
+#. type: Plain text
+#: build/C/man2/mmap.2:158
+msgid ""
+"Put the mapping into the first 2 Gigabytes of the process address space. "
+"This flag is supported only on x86-64, for 64-bit programs. It was added to "
+"allow thread stacks to be allocated somewhere in the first 2GB of memory, so "
+"as to improve context-switch performance on some early 64-bit processors. "
+"Modern x86-64 processors no longer have this performance problem, so use of "
+"this flag is not required on those systems. The B<MAP_32BIT> flag is "
+"ignored when B<MAP_FIXED> is set."
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mmap.2:158
+#, no-wrap
+msgid "B<MAP_ANON>"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:163
+msgid "Synonym for B<MAP_ANONYMOUS>. Deprecated."
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mmap.2:163
+#, no-wrap
+msgid "B<MAP_ANONYMOUS>"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:185
+msgid ""
+"The mapping is not backed by any file; its contents are initialized to "
+"zero. The I<fd> and I<offset> arguments are ignored; however, some "
+"implementations require I<fd> to be -1 if B<MAP_ANONYMOUS> (or B<MAP_ANON>) "
+"is specified, and portable applications should ensure this. The use of "
+"B<MAP_ANONYMOUS> in conjunction with B<MAP_SHARED> is supported on Linux "
+"only since kernel 2.4."
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mmap.2:185
+#, no-wrap
+msgid "B<MAP_DENYWRITE>"
+msgstr ""
+
+#. Introduced in 1.1.36, removed in 1.3.24.
+#. type: Plain text
+#: build/C/man2/mmap.2:193
+msgid ""
+"This flag is ignored. (Long ago, it signaled that attempts to write to the "
+"underlying file should fail with B<ETXTBUSY>. But this was a source of "
+"denial-of-service attacks.)"
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mmap.2:193
+#, no-wrap
+msgid "B<MAP_EXECUTABLE>"
+msgstr ""
+
+#. Introduced in 1.1.38, removed in 1.3.24. Flag tested in proc_follow_link.
+#. (Long ago, it signaled that the underlying file is an executable.
+#. However, that information was not really used anywhere.)
+#. Linus talked about DOS related to MAP_EXECUTABLE, but he was thinking of
+#. MAP_DENYWRITE?
+#. type: Plain text
+#: build/C/man2/mmap.2:201
+msgid "This flag is ignored."
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mmap.2:201
+#, no-wrap
+msgid "B<MAP_FILE>"
+msgstr ""
+
+#. On some systems, this was required as the opposite of
+#. MAP_ANONYMOUS -- mtk, 1 May 2007
+#. type: Plain text
+#: build/C/man2/mmap.2:207
+msgid "Compatibility flag. Ignored."
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mmap.2:207
+#, no-wrap
+msgid "B<MAP_FIXED>"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:225
+msgid ""
+"Don't interpret I<addr> as a hint: place the mapping at exactly that "
+"address. I<addr> must be a multiple of the page size. If the memory region "
+"specified by I<addr> and I<len> overlaps pages of any existing mapping(s), "
+"then the overlapped part of the existing mapping(s) will be discarded. If "
+"the specified address cannot be used, B<mmap>() will fail. Because "
+"requiring a fixed address for a mapping is less portable, the use of this "
+"option is discouraged."
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mmap.2:225
+#, no-wrap
+msgid "B<MAP_GROWSDOWN>"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:230
+msgid ""
+"Used for stacks. Indicates to the kernel virtual memory system that the "
+"mapping should extend downward in memory."
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mmap.2:230
+#, no-wrap
+msgid "B<MAP_HUGETLB> (since Linux 2.6.32)"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:236
+msgid ""
+"Allocate the mapping using \"huge pages.\" See the Linux kernel source file "
+"I<Documentation/vm/hugetlbpage.txt> for further information."
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mmap.2:236
+#, no-wrap
+msgid "B<MAP_LOCKED> (since Linux 2.5.37)"
+msgstr ""
+
+#. If set, the mapped pages will not be swapped out.
+#. type: Plain text
+#: build/C/man2/mmap.2:242
+msgid ""
+"Lock the pages of the mapped region into memory in the manner of "
+"B<mlock>(2). This flag is ignored in older kernels."
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mmap.2:242
+#, no-wrap
+msgid "B<MAP_NONBLOCK> (since Linux 2.5.46)"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:257
+msgid ""
+"Only meaningful in conjunction with B<MAP_POPULATE>. Don't perform "
+"read-ahead: create page tables entries only for pages that are already "
+"present in RAM. Since Linux 2.6.23, this flag causes B<MAP_POPULATE> to do "
+"nothing. One day the combination of B<MAP_POPULATE> and B<MAP_NONBLOCK> may "
+"be reimplemented."
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mmap.2:257
+#, no-wrap
+msgid "B<MAP_NORESERVE>"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:272
+msgid ""
+"Do not reserve swap space for this mapping. When swap space is reserved, "
+"one has the guarantee that it is possible to modify the mapping. When swap "
+"space is not reserved one might get B<SIGSEGV> upon a write if no physical "
+"memory is available. See also the discussion of the file "
+"I</proc/sys/vm/overcommit_memory> in B<proc>(5). In kernels before 2.6, "
+"this flag had effect only for private writable mappings."
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mmap.2:272
+#, no-wrap
+msgid "B<MAP_POPULATE> (since Linux 2.5.46)"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:279
+msgid ""
+"Populate (prefault) page tables for a mapping. For a file mapping, this "
+"causes read-ahead on the file. Later accesses to the mapping will not be "
+"blocked by page faults. B<MAP_POPULATE> is supported for private mappings "
+"only since Linux 2.6.23."
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mmap.2:279
+#, no-wrap
+msgid "B<MAP_STACK> (since Linux 2.6.27)"
+msgstr ""
+
+#. See http://lwn.net/Articles/294642 "Tangled up in threads", 19 Aug 08
+#. commit cd98a04a59e2f94fa64d5bf1e26498d27427d5e7
+#. http://thread.gmane.org/gmane.linux.kernel/720412
+#. "pthread_create() slow for many threads; also time to revisit 64b
+#. context switch optimization?"
+#. type: Plain text
+#: build/C/man2/mmap.2:292
+msgid ""
+"Allocate the mapping at an address suitable for a process or thread stack. "
+"This flag is currently a no-op, but is used in the glibc threading "
+"implementation so that if some architectures require special treatment for "
+"stack allocations, support can later be transparently implemented for glibc."
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mmap.2:292
+#, no-wrap
+msgid "B<MAP_UNINITIALIZED> (since Linux 2.6.33)"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:302
+msgid ""
+"Don't clear anonymous pages. This flag is intended to improve performance "
+"on embedded devices. This flag is honored only if the kernel was configured "
+"with the B<CONFIG_MMAP_ALLOW_UNINITIALIZED> option. Because of the security "
+"implications, that option is normally enabled only on embedded devices "
+"(i.e., devices where one has complete control of the contents of user "
+"memory)."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:310
+msgid ""
+"Of the above flags, only B<MAP_FIXED> is specified in POSIX.1-2001. "
+"However, most systems also support B<MAP_ANONYMOUS> (or its synonym "
+"B<MAP_ANON>)."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:317
+msgid ""
+"Some systems document the additional flags B<MAP_AUTOGROW>, "
+"B<MAP_AUTORESRV>, B<MAP_COPY>, and B<MAP_LOCAL>."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:323
+msgid ""
+"Memory mapped by B<mmap>() is preserved across B<fork>(2), with the same "
+"attributes."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:331
+msgid ""
+"A file is mapped in multiples of the page size. For a file that is not a "
+"multiple of the page size, the remaining memory is zeroed when mapped, and "
+"writes to that region are not written out to the file. The effect of "
+"changing the size of the underlying file of a mapping on the pages that "
+"correspond to added or removed regions of the file is unspecified."
+msgstr ""
+
+#. type: SS
+#: build/C/man2/mmap.2:331
+#, no-wrap
+msgid "munmap()"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:341
+msgid ""
+"The B<munmap>() system call deletes the mappings for the specified address "
+"range, and causes further references to addresses within the range to "
+"generate invalid memory references. The region is also automatically "
+"unmapped when the process is terminated. On the other hand, closing the "
+"file descriptor does not unmap the region."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:351
+msgid ""
+"The address I<addr> must be a multiple of the page size. All pages "
+"containing a part of the indicated range are unmapped, and subsequent "
+"references to these pages will generate B<SIGSEGV>. It is not an error if "
+"the indicated range does not contain any mapped pages."
+msgstr ""
+
+#. type: SS
+#: build/C/man2/mmap.2:351
+#, no-wrap
+msgid "Timestamps changes for file-backed mappings"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:358
+msgid ""
+"For file-backed mappings, the I<st_atime> field for the mapped file may be "
+"updated at any time between the B<mmap>() and the corresponding unmapping; "
+"the first reference to a mapped page will update the field if it has not "
+"been already."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:375
+msgid ""
+"The I<st_ctime> and I<st_mtime> field for a file mapped with B<PROT_WRITE> "
+"and B<MAP_SHARED> will be updated after a write to the mapped region, and "
+"before a subsequent B<msync>(2) with the B<MS_SYNC> or B<MS_ASYNC> flag, if "
+"one occurs."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:392
+msgid ""
+"On success, B<mmap>() returns a pointer to the mapped area. On error, the "
+"value B<MAP_FAILED> (that is, I<(void\\ *)\\ -1>) is returned, and I<errno> "
+"is set appropriately. On success, B<munmap>() returns 0, on failure -1, "
+"and I<errno> is set (probably to B<EINVAL>)."
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mmap.2:393 build/C/man2/mprotect.2:85 build/C/man3/shm_open.3:187 build/C/man3/shm_open.3:192 build/C/man2/shmctl.2:306 build/C/man2/shmget.2:192 build/C/man2/shmop.2:188
+#, no-wrap
+msgid "B<EACCES>"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:411
+msgid ""
+"A file descriptor refers to a non-regular file. Or a file mapping was "
+"requested, but I<fd> is not open for reading. Or B<MAP_SHARED> was "
+"requested and B<PROT_WRITE> is set, but I<fd> is not open in read/write "
+"(B<O_RDWR>) mode. Or B<PROT_WRITE> is set, but the file is append-only."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:415
+msgid ""
+"The file has been locked, or too much memory has been locked (see "
+"B<setrlimit>(2))."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:421
+msgid "I<fd> is not a valid file descriptor (and B<MAP_ANONYMOUS> was not set)."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:429
+msgid ""
+"We don't like I<addr>, I<length>, or I<offset> (e.g., they are too large, or "
+"not aligned on a page boundary)."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:434
+msgid "(since Linux 2.6.12) I<length> was 0."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:442
+msgid ""
+"I<flags> contained neither B<MAP_PRIVATE> or B<MAP_SHARED>, or contained "
+"both of these values."
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mmap.2:442 build/C/man3/shm_open.3:229 build/C/man2/shmget.2:221 build/C/man2/memfd_create.2:149
+#, no-wrap
+msgid "B<ENFILE>"
+msgstr ""
+
+#. [2.6.7] shmem_zero_setup()-->shmem_file_setup()-->get_empty_filp()
+#. type: Plain text
+#: build/C/man2/mmap.2:450 build/C/man2/shmget.2:225
+msgid "The system limit on the total number of open files has been reached."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:454
+msgid ""
+"The underlying filesystem of the specified file does not support memory "
+"mapping."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:458
+msgid ""
+"No memory is available, or the process's maximum number of mappings would "
+"have been exceeded."
+msgstr ""
+
+#. (Since 2.4.25 / 2.6.0.)
+#. type: Plain text
+#: build/C/man2/mmap.2:467
+msgid ""
+"The I<prot> argument asks for B<PROT_EXEC> but the mapped area belongs to a "
+"file on a filesystem that was mounted no-exec."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:477
+msgid ""
+"B<MAP_DENYWRITE> was set but the object specified by I<fd> is open for "
+"writing."
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mmap.2:477 build/C/man2/shmctl.2:348
+#, no-wrap
+msgid "B<EOVERFLOW>"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:489
+msgid ""
+"On 32-bit architecture together with the large file extension (i.e., using "
+"64-bit I<off_t>): the number of pages used for I<length> plus number of "
+"pages used for I<offset> would overflow I<unsigned long> (32 bits)."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:491
+msgid "Use of a mapped region can result in these signals:"
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mmap.2:491
+#, no-wrap
+msgid "B<SIGSEGV>"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:494
+msgid "Attempted write into a region mapped as read-only."
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mmap.2:494
+#, no-wrap
+msgid "B<SIGBUS>"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:499
+msgid ""
+"Attempted access to a portion of the buffer that does not correspond to the "
+"file (for example, beyond the end of the file, including the case where "
+"another process has truncated the file)."
+msgstr ""
+
+#. SVr4 documents additional error codes ENXIO and ENODEV.
+#. SUSv2 documents additional error codes EMFILE and EOVERFLOW.
+#. type: Plain text
+#: build/C/man2/mmap.2:503
+msgid "SVr4, 4.4BSD, POSIX.1-2001."
+msgstr ""
+
+#. POSIX.1-2001: It shall be defined to -1 or 0 or 200112L.
+#. -1: unavailable, 0: ask using sysconf().
+#. glibc defines it to 1.
+#. type: Plain text
+#: build/C/man2/mmap.2:517
+msgid ""
+"On POSIX systems on which B<mmap>(), B<msync>(2), and B<munmap>() are "
+"available, B<_POSIX_MAPPED_FILES> is defined in I<E<lt>unistd.hE<gt>> to a "
+"value greater than 0. (See also B<sysconf>(3).)"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:530
+msgid ""
+"On some hardware architectures (e.g., i386), B<PROT_WRITE> implies "
+"B<PROT_READ>. It is architecture dependent whether B<PROT_READ> implies "
+"B<PROT_EXEC> or not. Portable programs should always set B<PROT_EXEC> if "
+"they intend to execute code in the new mapping."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:545
+msgid ""
+"The portable way to create a mapping is to specify I<addr> as 0 (NULL), and "
+"omit B<MAP_FIXED> from I<flags>. In this case, the system chooses the "
+"address for the mapping; the address is chosen so as not to conflict with "
+"any existing mapping, and will not be 0. If the B<MAP_FIXED> flag is "
+"specified, and I<addr> is 0 (NULL), then the mapped address will be 0 "
+"(NULL)."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:575
+msgid ""
+"Certain I<flags> constants are defined only if either B<_BSD_SOURCE> or "
+"B<_SVID_SOURCE> is defined. (Requiring B<_GNU_SOURCE> also suffices, and "
+"requiring that macro specifically would have been more logical, since these "
+"flags are all Linux-specific.) The relevant flags are: B<MAP_32BIT>, "
+"B<MAP_ANONYMOUS> (and the synonym B<MAP_ANON>), B<MAP_DENYWRITE>, "
+"B<MAP_EXECUTABLE>, B<MAP_FILE>, B<MAP_GROWSDOWN>, B<MAP_HUGETLB>, "
+"B<MAP_LOCKED>, B<MAP_NONBLOCK>, B<MAP_NORESERVE>, B<MAP_POPULATE>, and "
+"B<MAP_STACK>."
+msgstr ""
+
+#. type: SS
+#: build/C/man2/mmap.2:575
+#, no-wrap
+msgid "C library/kernel ABI differences"
+msgstr ""
+
+#. Since around glibc 2.1/2.2, depending on the platform.
+#. type: Plain text
+#: build/C/man2/mmap.2:590
+msgid ""
+"This page describes the interface provided by the glibc B<mmap>() wrapper "
+"function. Originally, this function invoked a system call of the same "
+"name. Since kernel 2.4, that system call has been superseded by "
+"B<mmap2>(2), and nowadays the glibc B<mmap>() wrapper function invokes "
+"B<mmap2>(2) with a suitably adjusted value for I<offset>."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:595
+msgid ""
+"On Linux there are no guarantees like those suggested above under "
+"B<MAP_NORESERVE>. By default, any process can be killed at any moment when "
+"the system runs out of memory."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:602
+msgid ""
+"In kernels before 2.6.7, the B<MAP_POPULATE> flag has effect only if I<prot> "
+"is specified as B<PROT_NONE>."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:617
+msgid ""
+"SUSv3 specifies that B<mmap>() should fail if I<length> is 0. However, in "
+"kernels before 2.6.12, B<mmap>() succeeded in this case: no mapping was "
+"created and the call returned I<addr>. Since kernel 2.6.12, B<mmap>() "
+"fails with the error B<EINVAL> for this case."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:633
+msgid ""
+"POSIX specifies that the system shall always zero fill any partial page at "
+"the end of the object and that system will never write any modification of "
+"the object beyond its end. On Linux, when you write data to such partial "
+"page after the end of the object, the data stays in the page cache even "
+"after the file is closed and unmapped and even though the data is never "
+"written to the file itself, subsequent mappings may see the modified "
+"content. In some cases, this could be fixed by calling B<msync>(2) before "
+"the unmap takes place; however, this doesn't work on tmpfs (for example, "
+"when using POSIX shared memory interface documented in B<shm_overview>(7))."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:645
+msgid ""
+"The following program prints part of the file specified in its first "
+"command-line argument to standard output. The range of bytes to be printed "
+"is specified via offset and length values in the second and third "
+"command-line arguments. The program creates a memory mapping of the "
+"required pages of the file and then uses B<write>(2) to output the desired "
+"bytes."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:653
+#, no-wrap
+msgid ""
+"#include E<lt>sys/mman.hE<gt>\n"
+"#include E<lt>sys/stat.hE<gt>\n"
+"#include E<lt>fcntl.hE<gt>\n"
+"#include E<lt>stdio.hE<gt>\n"
+"#include E<lt>stdlib.hE<gt>\n"
+"#include E<lt>unistd.hE<gt>\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:656 build/C/man2/mprotect.2:177
+#, no-wrap
+msgid ""
+"#define handle_error(msg) \\e\n"
+" do { perror(msg); exit(EXIT_FAILURE); } while (0)\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:666
+#, no-wrap
+msgid ""
+"int\n"
+"main(int argc, char *argv[])\n"
+"{\n"
+" char *addr;\n"
+" int fd;\n"
+" struct stat sb;\n"
+" off_t offset, pa_offset;\n"
+" size_t length;\n"
+" ssize_t s;\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:671
+#, no-wrap
+msgid ""
+" if (argc E<lt> 3 || argc E<gt> 4) {\n"
+" fprintf(stderr, \"%s file offset [length]\\en\", argv[0]);\n"
+" exit(EXIT_FAILURE);\n"
+" }\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:675
+#, no-wrap
+msgid ""
+" fd = open(argv[1], O_RDONLY);\n"
+" if (fd == -1)\n"
+" handle_error(\"open\");\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:678
+#, no-wrap
+msgid ""
+" if (fstat(fd, &sb) == -1) /* To obtain file size */\n"
+" handle_error(\"fstat\");\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:682
+#, no-wrap
+msgid ""
+" offset = atoi(argv[2]);\n"
+" pa_offset = offset & ~(sysconf(_SC_PAGE_SIZE) - 1);\n"
+" /* offset for mmap() must be page aligned */\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:687
+#, no-wrap
+msgid ""
+" if (offset E<gt>= sb.st_size) {\n"
+" fprintf(stderr, \"offset is past end of file\\en\");\n"
+" exit(EXIT_FAILURE);\n"
+" }\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:693
+#, no-wrap
+msgid ""
+" if (argc == 4) {\n"
+" length = atoi(argv[3]);\n"
+" if (offset + length E<gt> sb.st_size)\n"
+" length = sb.st_size - offset;\n"
+" /* Can\\(aqt display bytes past end of file */\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:697
+#, no-wrap
+msgid ""
+" } else { /* No length arg ==E<gt> display to end of file */\n"
+" length = sb.st_size - offset;\n"
+" }\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:702
+#, no-wrap
+msgid ""
+" addr = mmap(NULL, length + offset - pa_offset, PROT_READ,\n"
+" MAP_PRIVATE, fd, pa_offset);\n"
+" if (addr == MAP_FAILED)\n"
+" handle_error(\"mmap\");\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:707
+#, no-wrap
+msgid ""
+" s = write(STDOUT_FILENO, addr + offset - pa_offset, length);\n"
+" if (s != length) {\n"
+" if (s == -1)\n"
+" handle_error(\"write\");\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:711
+#, no-wrap
+msgid ""
+" fprintf(stderr, \"partial write\");\n"
+" exit(EXIT_FAILURE);\n"
+" }\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:729
+msgid ""
+"B<getpagesize>(2), B<memfd_create>(2), B<mincore>(2), B<mlock>(2), "
+"B<mmap2>(2), B<mprotect>(2), B<mremap>(2), B<msync>(2), "
+"B<remap_file_pages>(2), B<setrlimit>(2), B<shmat>(2), B<shm_open>(3), "
+"B<shm_overview>(7)"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:736
+msgid ""
+"The descriptions of the following files in B<proc>(5): I</proc/[pid]/maps>, "
+"I</proc/[pid]/map_files>, and I</proc/[pid]/smaps>."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap.2:741 build/C/man2/msync.2:151
+msgid "B.O. Gallmeister, POSIX.4, O'Reilly, pp. 128-129 and 389-391."
+msgstr ""
+
+#. type: TH
+#: build/C/man2/mmap2.2:29
+#, no-wrap
+msgid "MMAP2"
+msgstr ""
+
+#. type: TH
+#: build/C/man2/mmap2.2:29
+#, no-wrap
+msgid "2014-02-25"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap2.2:32
+msgid "mmap2 - map files or devices into memory"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap2.2:38
+#, no-wrap
+msgid ""
+"B<void *mmap2(void *>I<addr>B<, size_t >I<length>B<, int >I<prot>B<,>\n"
+"B< int >I<flags>B<, int >I<fd>B<, off_t >I<pgoffset>B<);>\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap2.2:43
+msgid ""
+"This is probably not the system call that you are interested in; instead, "
+"see B<mmap>(2), which describes the glibc wrapper function that invokes this "
+"system call."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap2.2:54
+msgid ""
+"The B<mmap2>() system call provides the same interface as B<mmap>(2), "
+"except that the final argument specifies the offset into the file in "
+"4096-byte units (instead of bytes, as is done by B<mmap>(2)). This enables "
+"applications that use a 32-bit I<off_t> to map large files (up to 2^44 "
+"bytes)."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap2.2:61
+msgid ""
+"On success, B<mmap2>() returns a pointer to the mapped area. On error, -1 "
+"is returned and I<errno> is set appropriately."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap2.2:65
+msgid "Problem with getting the data from user space."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap2.2:70
+msgid ""
+"(Various platforms where the page size is not 4096 bytes.) I<offset\\ *\\ "
+"4096> is not a multiple of the system page size."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap2.2:74
+msgid "B<mmap2>() can also return any of the errors described in B<mmap>(2)."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap2.2:77
+msgid "B<mmap2>() is available since Linux 2.3.31."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap2.2:79 build/C/man2/subpage_prot.2:98
+msgid "This system call is Linux-specific."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap2.2:86
+msgid ""
+"On architectures where this system call is present, the glibc B<mmap>() "
+"wrapper function invokes this system call rather than the B<mmap>(2) system "
+"call."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap2.2:88
+msgid "This system call does not exist on x86-64."
+msgstr ""
+
+#. ia64 can have page sizes ranging from 4kB to 64kB.
+#. On cris, it looks like the unit might also be the page size,
+#. which is 8192 bytes. -- mtk, June 2007
+#. type: Plain text
+#: build/C/man2/mmap2.2:95
+msgid ""
+"On ia64, the unit for I<offset> is actually the system page size, rather "
+"than 4096 bytes."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mmap2.2:101
+msgid "B<getpagesize>(2), B<mmap>(2), B<mremap>(2), B<msync>(2), B<shm_open>(3)"
+msgstr ""
+
+#. type: TH
+#: build/C/man2/mprotect.2:39
+#, no-wrap
+msgid "MPROTECT"
+msgstr ""
+
+#. type: TH
+#: build/C/man2/mprotect.2:39
+#, no-wrap
+msgid "2014-01-05"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:42
+msgid "mprotect - set protection on a region of memory"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:47
+#, no-wrap
+msgid "B<int mprotect(void *>I<addr>B<, size_t >I<len>B<, int >I<prot>B<);>\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:55
+msgid ""
+"B<mprotect>() changes protection for the calling process's memory page(s) "
+"containing any part of the address range in the interval [I<addr>,\\ "
+"I<addr>+I<len>-1]. I<addr> must be aligned to a page boundary."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:60
+msgid ""
+"If the calling process tries to access memory in a manner that violates the "
+"protection, then the kernel generates a B<SIGSEGV> signal for the process."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:65
+msgid ""
+"I<prot> is either B<PROT_NONE> or a bitwise-or of the other values in the "
+"following list:"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:68
+msgid "The memory cannot be accessed at all."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:71
+msgid "The memory can be read."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:74
+msgid "The memory can be modified."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:77
+msgid "The memory can be executed."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:84
+msgid ""
+"On success, B<mprotect>() returns zero. On error, -1 is returned, and "
+"I<errno> is set appropriately."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:94
+msgid ""
+"The memory cannot be given the specified access. This can happen, for "
+"example, if you B<mmap>(2) a file to which you have read-only access, then "
+"ask B<mprotect>() to mark it B<PROT_WRITE>."
+msgstr ""
+
+#. Or: both PROT_GROWSUP and PROT_GROWSDOWN were specified in 'prot'.
+#. type: Plain text
+#: build/C/man2/mprotect.2:99
+msgid "I<addr> is not a valid pointer, or not a multiple of the system page size."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:102
+msgid "Internal kernel structures could not be allocated."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:112
+msgid ""
+"Addresses in the range [I<addr>, I<addr>+I<len>-1] are invalid for the "
+"address space of the process, or specify one or more pages that are not "
+"mapped. (Before kernel 2.4.19, the error B<EFAULT> was incorrectly produced "
+"for these cases.)"
+msgstr ""
+
+#. SVr4 defines an additional error
+#. code EAGAIN. The SVr4 error conditions don't map neatly onto Linux's.
+#. type: Plain text
+#: build/C/man2/mprotect.2:121
+msgid ""
+"SVr4, POSIX.1-2001. POSIX says that the behavior of B<mprotect>() is "
+"unspecified if it is applied to a region of memory that was not obtained via "
+"B<mmap>(2)."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:128
+msgid ""
+"On Linux it is always permissible to call B<mprotect>() on any address in a "
+"process's address space (except for the kernel vsyscall area). In "
+"particular it can be used to change existing code mappings to be writable."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:138
+msgid ""
+"Whether B<PROT_EXEC> has any effect different from B<PROT_READ> is "
+"architecture- and kernel version-dependent. On some hardware architectures "
+"(e.g., i386), B<PROT_WRITE> implies B<PROT_READ>."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:147
+msgid ""
+"POSIX.1-2001 says that an implementation may permit access other than that "
+"specified in I<prot>, but at a minimum can allow write access only if "
+"B<PROT_WRITE> has been set, and must not allow any access if B<PROT_NONE> "
+"has been set."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:153
+msgid ""
+"The program below allocates four pages of memory, makes the third of these "
+"pages read-only, and then executes a loop that walks upward through the "
+"allocated region modifying bytes."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:156
+msgid "An example of what we might see when running the program is the following:"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:162
+#, no-wrap
+msgid ""
+"$B< ./a.out>\n"
+"Start of region: 0x804c000\n"
+"Got SIGSEGV at address: 0x804e000\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:174
+#, no-wrap
+msgid ""
+"#include E<lt>unistd.hE<gt>\n"
+"#include E<lt>signal.hE<gt>\n"
+"#include E<lt>stdio.hE<gt>\n"
+"#include E<lt>malloc.hE<gt>\n"
+"#include E<lt>stdlib.hE<gt>\n"
+"#include E<lt>errno.hE<gt>\n"
+"#include E<lt>sys/mman.hE<gt>\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:179
+#, no-wrap
+msgid "static char *buffer;\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:187
+#, no-wrap
+msgid ""
+"static void\n"
+"handler(int sig, siginfo_t *si, void *unused)\n"
+"{\n"
+" printf(\"Got SIGSEGV at address: 0x%lx\\en\",\n"
+" (long) si-E<gt>si_addr);\n"
+" exit(EXIT_FAILURE);\n"
+"}\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:194
+#, no-wrap
+msgid ""
+"int\n"
+"main(int argc, char *argv[])\n"
+"{\n"
+" char *p;\n"
+" int pagesize;\n"
+" struct sigaction sa;\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:200
+#, no-wrap
+msgid ""
+" sa.sa_flags = SA_SIGINFO;\n"
+" sigemptyset(&sa.sa_mask);\n"
+" sa.sa_sigaction = handler;\n"
+" if (sigaction(SIGSEGV, &sa, NULL) == -1)\n"
+" handle_error(\"sigaction\");\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:204
+#, no-wrap
+msgid ""
+" pagesize = sysconf(_SC_PAGE_SIZE);\n"
+" if (pagesize == -1)\n"
+" handle_error(\"sysconf\");\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:207
+#, no-wrap
+msgid ""
+" /* Allocate a buffer aligned on a page boundary;\n"
+" initial protection is PROT_READ | PROT_WRITE */\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:211
+#, no-wrap
+msgid ""
+" buffer = memalign(pagesize, 4 * pagesize);\n"
+" if (buffer == NULL)\n"
+" handle_error(\"memalign\");\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:213
+#, no-wrap
+msgid " printf(\"Start of region: 0x%lx\\en\", (long) buffer);\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:217
+#, no-wrap
+msgid ""
+" if (mprotect(buffer + pagesize * 2, pagesize,\n"
+" PROT_READ) == -1)\n"
+" handle_error(\"mprotect\");\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:220
+#, no-wrap
+msgid ""
+" for (p = buffer ; ; )\n"
+" *(p++) = \\(aqa\\(aq;\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:224
+#, no-wrap
+msgid ""
+" printf(\"Loop completed\\en\"); /* Should never happen */\n"
+" exit(EXIT_SUCCESS);\n"
+"}\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mprotect.2:228
+msgid "B<mmap>(2), B<sysconf>(3)"
+msgstr ""
+
+#. type: TH
+#: build/C/man2/mremap.2:30
+#, no-wrap
+msgid "MREMAP"
+msgstr ""
+
+#. type: TH
+#: build/C/man2/mremap.2:30
+#, no-wrap
+msgid "2010-06-10"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mremap.2:33
+msgid "mremap - remap a virtual memory address"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mremap.2:36
+#, no-wrap
+msgid "B<#define _GNU_SOURCE> /* See feature_test_macros(7) */\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mremap.2:41
+#, no-wrap
+msgid ""
+"B<void *mremap(void *>I<old_address>B<, size_t >I<old_size>B<,>\n"
+"B< size_t >I<new_size>B<, int >I<flags>B<, ... /* void "
+"*>I<new_address>B< */);>\n"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mremap.2:47
+msgid ""
+"B<mremap>() expands (or shrinks) an existing memory mapping, potentially "
+"moving it at the same time (controlled by the I<flags> argument and the "
+"available virtual address space)."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mremap.2:61
+msgid ""
+"I<old_address> is the old address of the virtual memory block that you want "
+"to expand (or shrink). Note that I<old_address> has to be page aligned. "
+"I<old_size> is the old size of the virtual memory block. I<new_size> is the "
+"requested size of the virtual memory block after the resize. An optional "
+"fifth argument, I<new_address>, may be provided; see the description of "
+"B<MREMAP_FIXED> below."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mremap.2:73
+msgid ""
+"In Linux the memory is divided into pages. A user process has (one or) "
+"several linear virtual memory segments. Each virtual memory segment has one "
+"or more mappings to real memory pages (in the page table). Each virtual "
+"memory segment has its own protection (access rights), which may cause a "
+"segmentation violation if the memory is accessed incorrectly (e.g., writing "
+"to a read-only segment). Accessing virtual memory outside of the segments "
+"will also cause a segmentation violation."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mremap.2:81
+msgid ""
+"B<mremap>() uses the Linux page table scheme. B<mremap>() changes the "
+"mapping between virtual addresses and memory pages. This can be used to "
+"implement a very efficient B<realloc>(3)."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mremap.2:83
+msgid "The I<flags> bit-mask argument may be 0, or include the following flag:"
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mremap.2:83
+#, no-wrap
+msgid "B<MREMAP_MAYMOVE>"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mremap.2:95
+msgid ""
+"By default, if there is not sufficient space to expand a mapping at its "
+"current location, then B<mremap>() fails. If this flag is specified, then "
+"the kernel is permitted to relocate the mapping to a new virtual address, if "
+"necessary. If the mapping is relocated, then absolute pointers into the old "
+"mapping location become invalid (offsets relative to the starting address of "
+"the mapping should be employed)."
+msgstr ""
+
+#. type: TP
+#: build/C/man2/mremap.2:95
+#, no-wrap
+msgid "B<MREMAP_FIXED> (since Linux 2.3.31)"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mremap.2:117
+msgid ""
+"This flag serves a similar purpose to the B<MAP_FIXED> flag of B<mmap>(2). "
+"If this flag is specified, then B<mremap>() accepts a fifth argument, "
+"I<void\\ *new_address>, which specifies a page-aligned address to which the "
+"mapping must be moved. Any previous mapping at the address range specified "
+"by I<new_address> and I<new_size> is unmapped. If B<MREMAP_FIXED> is "
+"specified, then B<MREMAP_MAYMOVE> must also be specified."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mremap.2:127
+msgid ""
+"If the memory segment specified by I<old_address> and I<old_size> is locked "
+"(using B<mlock>(2) or similar), then this lock is maintained when the "
+"segment is resized and/or relocated. As a consequence, the amount of memory "
+"locked by the process may change."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mremap.2:135
+msgid ""
+"On success B<mremap>() returns a pointer to the new virtual memory area. "
+"On error, the value B<MAP_FAILED> (that is, I<(void\\ *)\\ -1>) is returned, "
+"and I<errno> is set appropriately."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mremap.2:142
+msgid ""
+"The caller tried to expand a memory segment that is locked, but this was not "
+"possible without exceeding the B<RLIMIT_MEMLOCK> resource limit."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mremap.2:151
+msgid ""
+"\"Segmentation fault.\" Some address in the range I<old_address> to "
+"I<old_address>+I<old_size> is an invalid virtual memory address for this "
+"process. You can also get B<EFAULT> even if there exist mappings that cover "
+"the whole address space requested, but those mappings are of different "
+"types."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mremap.2:179
+msgid ""
+"An invalid argument was given. Possible causes are: I<old_address> was not "
+"page aligned; a value other than B<MREMAP_MAYMOVE> or B<MREMAP_FIXED> was "
+"specified in I<flags>; I<new_size> was zero; I<new_size> or I<new_address> "
+"was invalid; or the new address range specified by I<new_address> and "
+"I<new_size> overlapped the old address range specified by I<old_address> and "
+"I<old_size>; or B<MREMAP_FIXED> was specified without also specifying "
+"B<MREMAP_MAYMOVE>."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mremap.2:185
+msgid ""
+"The memory area cannot be expanded at the current virtual address, and the "
+"B<MREMAP_MAYMOVE> flag is not set in I<flags>. Or, there is not enough "
+"(virtual) memory available."
+msgstr ""
+
+#. 4.2BSD had a (never actually implemented)
+#. .BR mremap (2)
+#. call with completely different semantics.
+#. type: Plain text
+#: build/C/man2/mremap.2:191
+msgid ""
+"This call is Linux-specific, and should not be used in programs intended to "
+"be portable."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mremap.2:199
+msgid ""
+"Prior to version 2.4, glibc did not expose the definition of "
+"B<MREMAP_FIXED>, and the prototype for B<mremap>() did not allow for the "
+"I<new_address> argument."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mremap.2:208
+msgid ""
+"B<brk>(2), B<getpagesize>(2), B<getrlimit>(2), B<mlock>(2), B<mmap>(2), "
+"B<sbrk>(2), B<malloc>(3), B<realloc>(3)"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/mremap.2:214
+msgid ""
+"Your favorite text book on operating systems for more information on paged "
+"memory (e.g., I<Modern Operating Systems> by Andrew S. Tanenbaum, I<Inside "
+"Linux> by Randolf Bentson, I<The Design of the UNIX Operating System> by "
+"Maurice J. Bach)"
+msgstr ""
+
+#. type: TH
+#: build/C/man2/msync.2:25
+#, no-wrap
+msgid "MSYNC"
+msgstr ""
+
+#. type: TH
+#: build/C/man2/msync.2:25
+#, no-wrap
+msgid "2014-04-20"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/msync.2:28
+msgid "msync - synchronize a file with a memory map"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:308
-msgid ""
-"Of the above flags, only B<MAP_FIXED> is specified in POSIX.1-2001. "
-"However, most systems also support B<MAP_ANONYMOUS> (or its synonym "
-"B<MAP_ANON>)."
+#: build/C/man2/msync.2:32
+msgid "B<int msync(void *>I<addr>B<, size_t >I<length>B<, int >I<flags>B<);>"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:315
+#: build/C/man2/msync.2:48
msgid ""
-"Some systems document the additional flags B<MAP_AUTOGROW>, "
-"B<MAP_AUTORESRV>, B<MAP_COPY>, and B<MAP_LOCAL>."
+"B<msync>() flushes changes made to the in-core copy of a file that was "
+"mapped into memory using B<mmap>(2) back to the filesystem. Without use of "
+"this call there is no guarantee that changes are written back before "
+"B<munmap>(2) is called. To be more precise, the part of the file that "
+"corresponds to the memory area starting at I<addr> and having length "
+"I<length> is updated."
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:321
+#: build/C/man2/msync.2:68
msgid ""
-"Memory mapped by B<mmap>() is preserved across B<fork>(2), with the same "
-"attributes."
+"The I<flags> argument may have the bits B<MS_ASYNC>, B<MS_SYNC>, and "
+"B<MS_INVALIDATE> set, but not both B<MS_ASYNC> and B<MS_SYNC>. B<MS_ASYNC> "
+"specifies that an update be scheduled, but the call returns immediately. "
+"B<MS_SYNC> asks for an update and waits for it to complete. "
+"B<MS_INVALIDATE> asks to invalidate other mappings of the same file (so that "
+"they can be updated with the fresh values just written)."
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:329
+#: build/C/man2/msync.2:73
msgid ""
-"A file is mapped in multiples of the page size. For a file that is not a "
-"multiple of the page size, the remaining memory is zeroed when mapped, and "
-"writes to that region are not written out to the file. The effect of "
-"changing the size of the underlying file of a mapping on the pages that "
-"correspond to added or removed regions of the file is unspecified."
+"On success, zero is returned. On error, -1 is returned, and I<errno> is set "
+"appropriately."
msgstr ""
-#. type: SS
-#: build/C/man2/mmap.2:329
+#. type: TP
+#: build/C/man2/msync.2:74
#, no-wrap
-msgid "munmap()"
+msgid "B<EBUSY>"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:339
+#: build/C/man2/msync.2:80
msgid ""
-"The B<munmap>() system call deletes the mappings for the specified address "
-"range, and causes further references to addresses within the range to "
-"generate invalid memory references. The region is also automatically "
-"unmapped when the process is terminated. On the other hand, closing the "
-"file descriptor does not unmap the region."
+"B<MS_INVALIDATE> was specified in I<flags>, and a memory lock exists for the "
+"specified address range."
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:349
+#: build/C/man2/msync.2:93
msgid ""
-"The address I<addr> must be a multiple of the page size. All pages "
-"containing a part of the indicated range are unmapped, and subsequent "
-"references to these pages will generate B<SIGSEGV>. It is not an error if "
-"the indicated range does not contain any mapped pages."
+"I<addr> is not a multiple of PAGESIZE; or any bit other than B<MS_ASYNC> | "
+"B<MS_INVALIDATE> | B<MS_SYNC> is set in I<flags>; or both B<MS_SYNC> and "
+"B<MS_ASYNC> are set in I<flags>."
msgstr ""
-#. type: SS
-#: build/C/man2/mmap.2:349
-#, no-wrap
-msgid "Timestamps changes for file-backed mappings"
+#. type: Plain text
+#: build/C/man2/msync.2:96
+msgid "The indicated memory (or part of it) was not mapped."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/msync.2:98 build/C/man3/posix_fallocate.3:110 build/C/man3/shm_open.3:253 build/C/man7/shm_overview.7:103
+msgid "POSIX.1-2001."
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:356
+#: build/C/man2/msync.2:105
msgid ""
-"For file-backed mappings, the I<st_atime> field for the mapped file may be "
-"updated at any time between the B<mmap>() and the corresponding unmapping; "
-"the first reference to a mapped page will update the field if it has not "
-"been already."
+"This call was introduced in Linux 1.3.21, and then used B<EFAULT> instead of "
+"B<ENOMEM>. In Linux 2.4.19, this was changed to the POSIX value B<ENOMEM>."
msgstr ""
+#. POSIX.1-2001: It shall be defined to -1 or 0 or 200112L.
+#. -1: unavailable, 0: ask using sysconf().
+#. glibc defines them to 1.
#. type: Plain text
-#: build/C/man2/mmap.2:373
+#: build/C/man2/msync.2:120
msgid ""
-"The I<st_ctime> and I<st_mtime> field for a file mapped with B<PROT_WRITE> "
-"and B<MAP_SHARED> will be updated after a write to the mapped region, and "
-"before a subsequent B<msync>(2) with the B<MS_SYNC> or B<MS_ASYNC> flag, if "
-"one occurs."
+"On POSIX systems on which B<msync>() is available, both "
+"B<_POSIX_MAPPED_FILES> and B<_POSIX_SYNCHRONIZED_IO> are defined in "
+"I<E<lt>unistd.hE<gt>> to a value greater than 0. (See also B<sysconf>(3).)"
msgstr ""
+#. commit 204ec841fbea3e5138168edbc3a76d46747cc987
#. type: Plain text
-#: build/C/man2/mmap.2:390
+#: build/C/man2/msync.2:147
msgid ""
-"On success, B<mmap>() returns a pointer to the mapped area. On error, the "
-"value B<MAP_FAILED> (that is, I<(void\\ *)\\ -1>) is returned, and I<errno> "
-"is set appropriately. On success, B<munmap>() returns 0, on failure -1, "
-"and I<errno> is set (probably to B<EINVAL>)."
+"According to POSIX, either B<MS_SYNC> or B<MS_ASYNC> must be specified in "
+"I<flags>, and indeed failure to include one of these flags will cause "
+"B<msync>() to fail on some systems. However, Linux permits a call to "
+"B<msync>() that specifies neither of these flags, with semantics that are "
+"(currently) equivalent to specifying B<MS_ASYNC>. (Since Linux 2.6.19, "
+"B<MS_ASYNC> is in fact a no-op, since the kernel properly tracks dirty pages "
+"and flushes them to storage as necessary.) Notwithstanding the Linux "
+"behavior, portable, future-proof applications should ensure that they "
+"specify either B<MS_SYNC> or B<MS_ASYNC> in I<flags>."
msgstr ""
#. type: TP
-#: build/C/man2/mmap.2:391 build/C/man2/mprotect.2:80 build/C/man3/shm_open.3:185 build/C/man3/shm_open.3:190 build/C/man2/shmctl.2:295 build/C/man2/shmget.2:186 build/C/man2/shmop.2:189
+#: build/C/man2/msync.2:149 build/C/man7/shm_overview.7:46
#, no-wrap
-msgid "B<EACCES>"
+msgid "B<mmap>(2)"
msgstr ""
-#. type: Plain text
-#: build/C/man2/mmap.2:411
-msgid ""
-"A file descriptor refers to a non-regular file. Or B<MAP_PRIVATE> was "
-"requested, but I<fd> is not open for reading. Or B<MAP_SHARED> was "
-"requested and B<PROT_WRITE> is set, but I<fd> is not open in read/write "
-"(B<O_RDWR>) mode. Or B<PROT_WRITE> is set, but the file is append-only."
+#. type: TH
+#: build/C/man3/mtrace.3:25
+#, no-wrap
+msgid "MTRACE"
msgstr ""
-#. type: Plain text
-#: build/C/man2/mmap.2:415
-msgid ""
-"The file has been locked, or too much memory has been locked (see "
-"B<setrlimit>(2))."
+#. type: TH
+#: build/C/man3/mtrace.3:25
+#, no-wrap
+msgid "2012-04-18"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:421
-msgid "I<fd> is not a valid file descriptor (and B<MAP_ANONYMOUS> was not set)."
+#: build/C/man3/mtrace.3:28
+msgid "mtrace, muntrace - malloc tracing"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:429
-msgid ""
-"We don't like I<addr>, I<length>, or I<offset> (e.g., they are too large, or "
-"not aligned on a page boundary)."
+#: build/C/man3/mtrace.3:30
+msgid "B<#include E<lt>mcheck.hE<gt>>"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:434
-msgid "(since Linux 2.6.12) I<length> was 0."
+#: build/C/man3/mtrace.3:32
+msgid "B<void mtrace(void);>"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:442
-msgid ""
-"I<flags> contained neither B<MAP_PRIVATE> or B<MAP_SHARED>, or contained "
-"both of these values."
-msgstr ""
-
-#. type: TP
-#: build/C/man2/mmap.2:442 build/C/man3/shm_open.3:227 build/C/man2/shmget.2:202
-#, no-wrap
-msgid "B<ENFILE>"
+#: build/C/man3/mtrace.3:34
+msgid "B<void muntrace(void);>"
msgstr ""
-#. [2.6.7] shmem_zero_setup()-->shmem_file_setup()-->get_empty_filp()
#. type: Plain text
-#: build/C/man2/mmap.2:450 build/C/man2/shmget.2:206
-msgid "The system limit on the total number of open files has been reached."
+#: build/C/man3/mtrace.3:46
+msgid ""
+"The B<mtrace>() function installs hook functions for the memory-allocation "
+"functions (B<malloc>(3), B<realloc>(3) B<memalign>(3), B<free>(3)). These "
+"hook functions record tracing information about memory allocation and "
+"deallocation. The tracing information can be used to discover memory leaks "
+"and attempts to free nonallocated memory in a program."
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:454
+#: build/C/man3/mtrace.3:57
msgid ""
-"The underlying file system of the specified file does not support memory "
-"mapping."
+"The B<muntrace>() function disables the hook functions installed by "
+"B<mtrace>(), so that tracing information is no longer recorded for the "
+"memory-allocation functions. If no hook functions were successfully "
+"installed by B<mtrace>(), B<muntrace>() does nothing."
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:458
+#: build/C/man3/mtrace.3:65
msgid ""
-"No memory is available, or the process's maximum number of mappings would "
-"have been exceeded."
+"When B<mtrace>() is called, it checks the value of the environment variable "
+"B<MALLOC_TRACE>, which should contain the pathname of a file in which the "
+"tracing information is to be recorded. If the pathname is successfully "
+"opened, it is truncated to zero length."
msgstr ""
-#. (Since 2.4.25 / 2.6.0.)
#. type: Plain text
-#: build/C/man2/mmap.2:467
+#: build/C/man3/mtrace.3:78
msgid ""
-"The I<prot> argument asks for B<PROT_EXEC> but the mapped area belongs to a "
-"file on a file system that was mounted no-exec."
+"If B<MALLOC_TRACE> is not set, or the pathname it specifies is invalid or "
+"not writable, then no hook functions are installed, and B<mtrace>() has no "
+"effect. In set-user-ID and set-group-ID programs, B<MALLOC_TRACE> is "
+"ignored, and B<mtrace>() has no effect."
msgstr ""
-#. type: TP
-#: build/C/man2/mmap.2:467
-#, no-wrap
-msgid "B<ETXTBSY>"
+#. type: Plain text
+#: build/C/man3/mtrace.3:86
+msgid ""
+"In normal usage, B<mtrace>() is called once at the start of execution of a "
+"program, and B<muntrace>() is never called."
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:473
+#: build/C/man3/mtrace.3:96
msgid ""
-"B<MAP_DENYWRITE> was set but the object specified by I<fd> is open for "
-"writing."
+"The tracing output produced after a call to B<mtrace>() is textual, but not "
+"designed to be human readable. The GNU C library provides a Perl script, "
+"B<mtrace>(1), that interprets the trace log and produces human-readable "
+"output. For best results, the traced program should be compiled with "
+"debugging enabled, so that line-number information is recorded in the "
+"executable."
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:475
-msgid "Use of a mapped region can result in these signals:"
+#: build/C/man3/mtrace.3:102
+msgid ""
+"The tracing performed by B<mtrace>() incurs a performance penalty (if "
+"B<MALLOC_TRACE> points to a valid, writable pathname)."
msgstr ""
-#. type: TP
-#: build/C/man2/mmap.2:475
-#, no-wrap
-msgid "B<SIGSEGV>"
+#. type: Plain text
+#: build/C/man3/mtrace.3:108
+msgid ""
+"The line-number information produced by B<mtrace>(1) is not always precise: "
+"the line number references may refer to the previous or following (nonblank) "
+"line of the source code."
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:478
-msgid "Attempted write into a region mapped as read-only."
+#: build/C/man3/mtrace.3:115
+msgid ""
+"The shell session below demonstrates the use of the B<mtrace>() function "
+"and the B<mtrace>(1) command in a program that has memory leaks at two "
+"different locations. The demonstration uses the following program:"
msgstr ""
-#. type: TP
-#: build/C/man2/mmap.2:478
+#. type: Plain text
+#: build/C/man3/mtrace.3:122
#, no-wrap
-msgid "B<SIGBUS>"
+msgid ""
+"$ B<cat t_mtrace.c>\n"
+"#include E<lt>mcheck.hE<gt>\n"
+"#include E<lt>stdlib.hE<gt>\n"
+"#include E<lt>stdio.hE<gt>\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:483
+#: build/C/man3/mtrace.3:127
+#, no-wrap
msgid ""
-"Attempted access to a portion of the buffer that does not correspond to the "
-"file (for example, beyond the end of the file, including the case where "
-"another process has truncated the file)."
+"int\n"
+"main(int argc, char *argv[])\n"
+"{\n"
+" int j;\n"
msgstr ""
-#. SVr4 documents additional error codes ENXIO and ENODEV.
-#. SUSv2 documents additional error codes EMFILE and EOVERFLOW.
#. type: Plain text
-#: build/C/man2/mmap.2:487
-msgid "SVr4, 4.4BSD, POSIX.1-2001."
+#: build/C/man3/mtrace.3:129
+#, no-wrap
+msgid " mtrace();\n"
msgstr ""
-#. POSIX.1-2001: It shall be defined to -1 or 0 or 200112L.
-#. -1: unavailable, 0: ask using sysconf().
-#. glibc defines it to 1.
#. type: Plain text
-#: build/C/man2/mmap.2:501
+#: build/C/man3/mtrace.3:132
+#, no-wrap
msgid ""
-"On POSIX systems on which B<mmap>(), B<msync>(2) and B<munmap>() are "
-"available, B<_POSIX_MAPPED_FILES> is defined in I<E<lt>unistd.hE<gt>> to a "
-"value greater than 0. (See also B<sysconf>(3).)"
+" for (j = 0; j E<lt> 2; j++)\n"
+" malloc(100); /* Never freed--a memory leak */\n"
msgstr ""
-#. Since around glibc 2.1/2.2, depending on the platform.
#. type: Plain text
-#: build/C/man2/mmap.2:516
+#: build/C/man3/mtrace.3:136
+#, no-wrap
msgid ""
-"This page describes the interface provided by the glibc B<mmap>() wrapper "
-"function. Originally, this function invoked a system call of the same "
-"name. Since kernel 2.4, that system call has been superseded by "
-"B<mmap2>(2), and nowadays the glibc B<mmap>() wrapper function invokes "
-"B<mmap2>(2) with a suitably adjusted value for I<offset>."
+" calloc(16, 16); /* Never freed--a memory leak */\n"
+" exit(EXIT_SUCCESS);\n"
+"}\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:529
+#: build/C/man3/mtrace.3:142
msgid ""
-"On some hardware architectures (e.g., i386), B<PROT_WRITE> implies "
-"B<PROT_READ>. It is architecture dependent whether B<PROT_READ> implies "
-"B<PROT_EXEC> or not. Portable programs should always set B<PROT_EXEC> if "
-"they intend to execute code in the new mapping."
+"When we run the program as follows, we see that B<mtrace>() diagnosed "
+"memory leaks at two different locations in the program:"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:544
+#: build/C/man3/mtrace.3:155
+#, no-wrap
msgid ""
-"The portable way to create a mapping is to specify I<addr> as 0 (NULL), and "
-"omit B<MAP_FIXED> from I<flags>. In this case, the system chooses the "
-"address for the mapping; the address is chosen so as not to conflict with "
-"any existing mapping, and will not be 0. If the B<MAP_FIXED> flag is "
-"specified, and I<addr> is 0 (NULL), then the mapped address will be 0 "
-"(NULL)."
+"$ B<cc -g t_mtrace.c -o t_mtrace>\n"
+"$ B<export MALLOC_TRACE=/tmp/t>\n"
+"$ B<./t_mtrace>\n"
+"$ B<mtrace ./t_mtrace $MALLOC_TRACE>\n"
+"Memory not freed:\n"
+"-----------------\n"
+" Address Size Caller\n"
+"0x084c9378 0x64 at /home/cecilia/t_mtrace.c:12\n"
+"0x084c93e0 0x64 at /home/cecilia/t_mtrace.c:12\n"
+"0x084c9448 0x100 at /home/cecilia/t_mtrace.c:16\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:549
+#: build/C/man3/mtrace.3:167
msgid ""
-"On Linux there are no guarantees like those suggested above under "
-"B<MAP_NORESERVE>. By default, any process can be killed at any moment when "
-"the system runs out of memory."
+"The first two messages about unfreed memory correspond to the two "
+"B<malloc>(3) calls inside the I<for> loop. The final message corresponds "
+"to the call to B<calloc>(3) (which in turn calls B<malloc>(3))."
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:556
-msgid ""
-"In kernels before 2.6.7, the B<MAP_POPULATE> flag only has effect if I<prot> "
-"is specified as B<PROT_NONE>."
+#: build/C/man3/mtrace.3:172
+msgid "B<mtrace>(1), B<malloc>(3), B<malloc_hook>(3), B<mcheck>(3)"
msgstr ""
-#. type: Plain text
-#: build/C/man2/mmap.2:571
-msgid ""
-"SUSv3 specifies that B<mmap>() should fail if I<length> is 0. However, in "
-"kernels before 2.6.12, B<mmap>() succeeded in this case: no mapping was "
-"created and the call returned I<addr>. Since kernel 2.6.12, B<mmap>() "
-"fails with the error B<EINVAL> for this case."
+#. type: TH
+#: build/C/man2/posix_fadvise.2:28
+#, no-wrap
+msgid "POSIX_FADVISE"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:583
-msgid ""
-"The following program prints part of the file specified in its first "
-"command-line argument to standard output. The range of bytes to be printed "
-"is specified via offset and length values in the second and third "
-"command-line arguments. The program creates a memory mapping of the "
-"required pages of the file and then uses B<write>(2) to output the desired "
-"bytes."
+#: build/C/man2/posix_fadvise.2:31
+msgid "posix_fadvise - predeclare an access pattern for file data"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:591
+#: build/C/man2/posix_fadvise.2:34 build/C/man3/posix_fallocate.3:31
#, no-wrap
-msgid ""
-"#include E<lt>sys/mman.hE<gt>\n"
-"#include E<lt>sys/stat.hE<gt>\n"
-"#include E<lt>fcntl.hE<gt>\n"
-"#include E<lt>stdio.hE<gt>\n"
-"#include E<lt>stdlib.hE<gt>\n"
-"#include E<lt>unistd.hE<gt>\n"
+msgid "B<#include E<lt>fcntl.hE<gt>>\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:594 build/C/man2/mprotect.2:172
+#: build/C/man2/posix_fadvise.2:37
#, no-wrap
msgid ""
-"#define handle_error(msg) \\e\n"
-" do { perror(msg); exit(EXIT_FAILURE); } while (0)\n"
+"B<int posix_fadvise(int >I<fd>B<, off_t >I<offset>B<, off_t >I<len>B<, int "
+">I<advice>B<);>\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:604
-#, no-wrap
-msgid ""
-"int\n"
-"main(int argc, char *argv[])\n"
-"{\n"
-" char *addr;\n"
-" int fd;\n"
-" struct stat sb;\n"
-" off_t offset, pa_offset;\n"
-" size_t length;\n"
-" ssize_t s;\n"
+#: build/C/man2/posix_fadvise.2:46
+msgid "B<posix_fadvise>():"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:609
-#, no-wrap
-msgid ""
-" if (argc E<lt> 3 || argc E<gt> 4) {\n"
-" fprintf(stderr, \"%s file offset [length]\\en\", argv[0]);\n"
-" exit(EXIT_FAILURE);\n"
-" }\n"
+#: build/C/man2/posix_fadvise.2:48 build/C/man3/posix_fallocate.3:44
+msgid "_XOPEN_SOURCE\\ E<gt>=\\ 600 || _POSIX_C_SOURCE\\ E<gt>=\\ 200112L"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:613
-#, no-wrap
+#: build/C/man2/posix_fadvise.2:56
msgid ""
-" fd = open(argv[1], O_RDONLY);\n"
-" if (fd == -1)\n"
-" handle_error(\"open\");\n"
+"Programs can use B<posix_fadvise>() to announce an intention to access file "
+"data in a specific pattern in the future, thus allowing the kernel to "
+"perform appropriate optimizations."
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:616
-#, no-wrap
+#: build/C/man2/posix_fadvise.2:63
msgid ""
-" if (fstat(fd, &sb) == -1) /* To obtain file size */\n"
-" handle_error(\"fstat\");\n"
+"The I<advice> applies to a (not necessarily existent) region starting at "
+"I<offset> and extending for I<len> bytes (or until the end of the file if "
+"I<len> is 0) within the file referred to by I<fd>. The I<advice> is not "
+"binding; it merely constitutes an expectation on behalf of the application."
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:620
-#, no-wrap
-msgid ""
-" offset = atoi(argv[2]);\n"
-" pa_offset = offset & ~(sysconf(_SC_PAGE_SIZE) - 1);\n"
-" /* offset for mmap() must be page aligned */\n"
+#: build/C/man2/posix_fadvise.2:65
+msgid "Permissible values for I<advice> include:"
msgstr ""
-#. type: Plain text
-#: build/C/man2/mmap.2:625
+#. type: TP
+#: build/C/man2/posix_fadvise.2:65
#, no-wrap
-msgid ""
-" if (offset E<gt>= sb.st_size) {\n"
-" fprintf(stderr, \"offset is past end of file\\en\");\n"
-" exit(EXIT_FAILURE);\n"
-" }\n"
+msgid "B<POSIX_FADV_NORMAL>"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:631
-#, no-wrap
+#: build/C/man2/posix_fadvise.2:71
msgid ""
-" if (argc == 4) {\n"
-" length = atoi(argv[3]);\n"
-" if (offset + length E<gt> sb.st_size)\n"
-" length = sb.st_size - offset;\n"
-" /* Can\\(aqt display bytes past end of file */\n"
+"Indicates that the application has no advice to give about its access "
+"pattern for the specified data. If no advice is given for an open file, "
+"this is the default assumption."
msgstr ""
-#. type: Plain text
-#: build/C/man2/mmap.2:635
+#. type: TP
+#: build/C/man2/posix_fadvise.2:71
#, no-wrap
-msgid ""
-" } else { /* No length arg ==E<gt> display to end of file */\n"
-" length = sb.st_size - offset;\n"
-" }\n"
+msgid "B<POSIX_FADV_SEQUENTIAL>"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:640
-#, no-wrap
+#: build/C/man2/posix_fadvise.2:75
msgid ""
-" addr = mmap(NULL, length + offset - pa_offset, PROT_READ,\n"
-" MAP_PRIVATE, fd, pa_offset);\n"
-" if (addr == MAP_FAILED)\n"
-" handle_error(\"mmap\");\n"
+"The application expects to access the specified data sequentially (with "
+"lower offsets read before higher ones)."
msgstr ""
-#. type: Plain text
-#: build/C/man2/mmap.2:645
+#. type: TP
+#: build/C/man2/posix_fadvise.2:75
#, no-wrap
-msgid ""
-" s = write(STDOUT_FILENO, addr + offset - pa_offset, length);\n"
-" if (s != length) {\n"
-" if (s == -1)\n"
-" handle_error(\"write\");\n"
+msgid "B<POSIX_FADV_RANDOM>"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:649
+#: build/C/man2/posix_fadvise.2:78
+msgid "The specified data will be accessed in random order."
+msgstr ""
+
+#. type: TP
+#: build/C/man2/posix_fadvise.2:78
#, no-wrap
-msgid ""
-" fprintf(stderr, \"partial write\");\n"
-" exit(EXIT_FAILURE);\n"
-" }\n"
+msgid "B<POSIX_FADV_NOREUSE>"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:666
-msgid ""
-"B<getpagesize>(2), B<mincore>(2), B<mlock>(2), B<mmap2>(2), B<mprotect>(2), "
-"B<mremap>(2), B<msync>(2), B<remap_file_pages>(2), B<setrlimit>(2), "
-"B<shmat>(2), B<shm_open>(3), B<shm_overview>(7)"
+#: build/C/man2/posix_fadvise.2:81
+msgid "The specified data will be accessed only once."
+msgstr ""
+
+#. type: TP
+#: build/C/man2/posix_fadvise.2:81
+#, no-wrap
+msgid "B<POSIX_FADV_WILLNEED>"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap.2:667 build/C/man2/msync.2:121
-msgid "B.O. Gallmeister, POSIX.4, O'Reilly, pp. 128-129 and 389-391."
+#: build/C/man2/posix_fadvise.2:84
+msgid "The specified data will be accessed in the near future."
msgstr ""
-#. type: TH
-#: build/C/man2/mmap2.2:29
+#. type: TP
+#: build/C/man2/posix_fadvise.2:84
#, no-wrap
-msgid "MMAP2"
+msgid "B<POSIX_FADV_DONTNEED>"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap2.2:32
-msgid "mmap2 - map files or devices into memory"
+#: build/C/man2/posix_fadvise.2:87
+msgid "The specified data will not be accessed in the near future."
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap2.2:38
-#, no-wrap
-msgid ""
-"B<void *mmap2(void *>I<addr>B<, size_t >I<length>B<, int >I<prot>B<,>\n"
-"B< int >I<flags>B<, int >I<fd>B<, off_t >I<pgoffset>B<);>\n"
+#: build/C/man2/posix_fadvise.2:90
+msgid "On success, zero is returned. On error, an error number is returned."
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap2.2:43
-msgid ""
-"This is probably not the system call you are interested; instead, see "
-"B<mmap>(2), which describes the glibc wrapper function that invokes this "
-"system call."
+#: build/C/man2/posix_fadvise.2:94
+msgid "The I<fd> argument was not a valid file descriptor."
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap2.2:54
+#: build/C/man2/posix_fadvise.2:97
+msgid "An invalid value was specified for I<advice>."
+msgstr ""
+
+#. commit 87ba81dba431232548ce29d5d224115d0c2355ac
+#. type: Plain text
+#: build/C/man2/posix_fadvise.2:107
msgid ""
-"The B<mmap2>() system call provides the same interface as B<mmap>(2), "
-"except that the final argument specifies the offset into the file in "
-"4096-byte units (instead of bytes, as is done by B<mmap>(2)). This enables "
-"applications that use a 32-bit I<off_t> to map large files (up to 2^44 "
-"bytes)."
+"The specified file descriptor refers to a pipe or FIFO. (B<ESPIPE> is the "
+"error specified by POSIX, but before kernel version 2.16, Linux returned "
+"B<EINVAL> in this case.)"
msgstr ""
+#. of fadvise64_64()
#. type: Plain text
-#: build/C/man2/mmap2.2:61
+#: build/C/man2/posix_fadvise.2:115
msgid ""
-"On success, B<mmap2>() returns a pointer to the mapped area. On error -1 "
-"is returned and I<errno> is set appropriately."
+"Kernel support first appeared in Linux 2.5.60; the underlying system call is "
+"called B<fadvise64>(). Library support has been provided since glibc "
+"version 2.2, via the wrapper function B<posix_fadvise>()."
msgstr ""
+#. commit d3ac21cacc24790eb45d735769f35753f5b56ceb
#. type: Plain text
-#: build/C/man2/mmap2.2:65
-msgid "Problem with getting the data from userspace."
+#: build/C/man2/posix_fadvise.2:122
+msgid ""
+"Since Linux 3.18, support for the underlying system call is optional, "
+"depending on the setting of the B<CONFIG_ADVISE_SYSCALLS> configuration "
+"option."
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap2.2:70
+#: build/C/man2/posix_fadvise.2:131
msgid ""
-"(Various platforms where the page size is not 4096 bytes.) I<offset * 4096> "
-"is not a multiple of the system page size."
+"POSIX.1-2001. Note that the type of the I<len> argument was changed from "
+"I<size_t> to I<off_t> in POSIX.1-2003 TC1."
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap2.2:74
-msgid "B<mmap2>() can also return any of the errors described in B<mmap>(2)."
+#: build/C/man2/posix_fadvise.2:137
+msgid ""
+"Under Linux, B<POSIX_FADV_NORMAL> sets the readahead window to the default "
+"size for the backing device; B<POSIX_FADV_SEQUENTIAL> doubles this size, and "
+"B<POSIX_FADV_RANDOM> disables file readahead entirely. These changes affect "
+"the entire file, not just the specified region (but other open file handles "
+"to the same file are unaffected)."
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap2.2:77
-msgid "B<mmap2>() is available since Linux 2.3.31."
+#: build/C/man2/posix_fadvise.2:144
+msgid ""
+"B<POSIX_FADV_WILLNEED> initiates a nonblocking read of the specified region "
+"into the page cache. The amount of data read may be decreased by the kernel "
+"depending on virtual memory load. (A few megabytes will usually be fully "
+"satisfied, and more is rarely useful.)"
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap2.2:79 build/C/man2/subpage_prot.2:93
-msgid "This system call is Linux-specific."
+#: build/C/man2/posix_fadvise.2:148
+msgid ""
+"In kernels before 2.6.18, B<POSIX_FADV_NOREUSE> had the same semantics as "
+"B<POSIX_FADV_WILLNEED>. This was probably a bug; since kernel 2.6.18, this "
+"flag is a no-op."
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap2.2:85
+#: build/C/man2/posix_fadvise.2:156
msgid ""
-"Nowadays, the glibc B<mmap>() wrapper function invokes this system call "
-"rather than the B<mmap>(2) system call."
+"B<POSIX_FADV_DONTNEED> attempts to free cached pages associated with the "
+"specified region. This is useful, for example, while streaming large "
+"files. A program may periodically request the kernel to free cached data "
+"that has already been used, so that more useful cached pages are not "
+"discarded instead."
msgstr ""
-#. ia64 can have page sizes ranging from 4kB to 64kB.
-#. On cris, it looks like the unit might also be the page size,
-#. which is 8192 bytes. -- mtk, June 2007
#. type: Plain text
-#: build/C/man2/mmap2.2:92
+#: build/C/man2/posix_fadvise.2:164
msgid ""
-"On ia64, the unit for I<offset> is actually the system page size, rather "
-"than 4096 bytes."
+"Requests to discard partial pages are ignored. It is preferable to preserve "
+"needed data than discard unneeded data. If the application requires that "
+"data be considered for discarding then I<offset> and I<len> must be "
+"page-aligned."
msgstr ""
#. type: Plain text
-#: build/C/man2/mmap2.2:97
-msgid "B<getpagesize>(2), B<mmap>(2), B<mremap>(2), B<msync>(2), B<shm_open>(3)"
+#: build/C/man2/posix_fadvise.2:172
+msgid ""
+"Pages that have not yet been written out will be unaffected, so if the "
+"application wishes to guarantee that pages will be released, it should call "
+"B<fsync>(2) or B<fdatasync>(2) first."
msgstr ""
-#. type: TH
-#: build/C/man2/mprotect.2:32
+#. type: SS
+#: build/C/man2/posix_fadvise.2:172
#, no-wrap
-msgid "MPROTECT"
+msgid "Architecture-specific variants"
msgstr ""
-#. type: TH
-#: build/C/man2/mprotect.2:32
-#, no-wrap
-msgid "2011-09-08"
+#. type: Plain text
+#: build/C/man2/posix_fadvise.2:189
+msgid ""
+"Some architectures require 64-bit arguments to be aligned in a suitable pair "
+"of registers (see B<syscall>(2) for further detail). On such "
+"architectures, the call signature of B<posix_fadvise>() shown in the "
+"SYNOPSIS would force a register to be wasted as padding between the I<fd> "
+"and I<offset> arguments. Therefore, these architectures define a version of "
+"the system call that orders the arguments suitably, but otherwise is "
+"otherwise exactly the same as B<posix_fadvise>()."
msgstr ""
#. type: Plain text
-#: build/C/man2/mprotect.2:35
-msgid "mprotect - set protection on a region of memory"
+#: build/C/man2/posix_fadvise.2:191
+msgid "For example, since Linux 2.6.14, ARM has the following system call:"
msgstr ""
#. type: Plain text
-#: build/C/man2/mprotect.2:40
+#: build/C/man2/posix_fadvise.2:196
#, no-wrap
-msgid "B<int mprotect(const void *>I<addr>B<, size_t >I<len>B<, int >I<prot>B<);>\n"
+msgid ""
+"B<long arm_fadvise64_64(int >I<fd>B<, int >I<advice>B<,>\n"
+"B< loff_t >I<offset>B<, loff_t >I<len>B<);>\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/mprotect.2:48
+#: build/C/man2/posix_fadvise.2:204
msgid ""
-"B<mprotect>() changes protection for the calling process's memory page(s) "
-"containing any part of the address range in the interval [I<addr>,\\ "
-"I<addr>+I<len>-1]. I<addr> must be aligned to a page boundary."
+"These architecture-specific details are generally hidden from applications "
+"by the glibc B<posix_fadvise>() wrapper function, which invokes the "
+"appropriate architecture-specific system call."
msgstr ""
#. type: Plain text
-#: build/C/man2/mprotect.2:53
+#: build/C/man2/posix_fadvise.2:209
msgid ""
-"If the calling process tries to access memory in a manner that violates the "
-"protection, then the kernel generates a B<SIGSEGV> signal for the process."
+"In kernels before 2.6.6, if I<len> was specified as 0, then this was "
+"interpreted literally as \"zero bytes\", rather than as meaning \"all bytes "
+"through to the end of the file\"."
msgstr ""
+#. FIXME . Write a posix_fadvise(3) page.
#. type: Plain text
-#: build/C/man2/mprotect.2:58
+#: build/C/man2/posix_fadvise.2:215
msgid ""
-"I<prot> is either B<PROT_NONE> or a bitwise-or of the other values in the "
-"following list:"
+"B<readahead>(2), B<sync_file_range>(2), B<posix_fallocate>(3), "
+"B<posix_madvise>(3)"
+msgstr ""
+
+#. type: TH
+#: build/C/man3/posix_fallocate.3:25
+#, no-wrap
+msgid "POSIX_FALLOCATE"
msgstr ""
#. type: Plain text
-#: build/C/man2/mprotect.2:61
-msgid "The memory cannot be accessed at all."
+#: build/C/man3/posix_fallocate.3:28
+msgid "posix_fallocate - allocate file space"
msgstr ""
#. type: Plain text
-#: build/C/man2/mprotect.2:64
-msgid "The memory can be read."
+#: build/C/man3/posix_fallocate.3:33
+#, no-wrap
+msgid "B<int posix_fallocate(int >I<fd>B<, off_t >I<offset>B<, off_t >I<len>B<);>\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/mprotect.2:67
-msgid "The memory can be modified."
+#: build/C/man3/posix_fallocate.3:42
+msgid "B<posix_fallocate>():"
msgstr ""
-#. FIXME
-#. Document PROT_GROWSUP and PROT_GROWSDOWN
#. type: Plain text
-#: build/C/man2/mprotect.2:72
-msgid "The memory can be executed."
+#: build/C/man3/posix_fallocate.3:61
+msgid ""
+"The function B<posix_fallocate>() ensures that disk space is allocated for "
+"the file referred to by the descriptor I<fd> for the bytes in the range "
+"starting at I<offset> and continuing for I<len> bytes. After a successful "
+"call to B<posix_fallocate>(), subsequent writes to bytes in the specified "
+"range are guaranteed not to fail because of lack of disk space."
msgstr ""
#. type: Plain text
-#: build/C/man2/mprotect.2:79
+#: build/C/man3/posix_fallocate.3:66
msgid ""
-"On success, B<mprotect>() returns zero. On error, -1 is returned, and "
-"I<errno> is set appropriately."
+"If the size of the file is less than I<offset>+I<len>, then the file is "
+"increased to this size; otherwise the file size is left unchanged."
msgstr ""
#. type: Plain text
-#: build/C/man2/mprotect.2:89
+#: build/C/man3/posix_fallocate.3:72
msgid ""
-"The memory cannot be given the specified access. This can happen, for "
-"example, if you B<mmap>(2) a file to which you have read-only access, then "
-"ask B<mprotect>() to mark it B<PROT_WRITE>."
+"B<posix_fallocate>() returns zero on success, or an error number on "
+"failure. Note that I<errno> is not set."
msgstr ""
-#. Or: both PROT_GROWSUP and PROT_GROWSDOWN were specified in 'prot'.
#. type: Plain text
-#: build/C/man2/mprotect.2:94
-msgid "I<addr> is not a valid pointer, or not a multiple of the system page size."
+#: build/C/man3/posix_fallocate.3:81
+msgid "I<offset+len> exceeds the maximum file size."
msgstr ""
#. type: Plain text
-#: build/C/man2/mprotect.2:97
-msgid "Internal kernel structures could not be allocated."
+#: build/C/man3/posix_fallocate.3:91
+msgid "I<fd> does not refer to a regular file."
msgstr ""
#. type: Plain text
-#: build/C/man2/mprotect.2:107
-msgid ""
-"Addresses in the range [I<addr>, I<addr>+I<len>-1] are invalid for the "
-"address space of the process, or specify one or more pages that are not "
-"mapped. (Before kernel 2.4.19, the error B<EFAULT> was incorrectly produced "
-"for these cases.)"
+#: build/C/man3/posix_fallocate.3:100
+msgid "I<fd> refers to a pipe."
msgstr ""
-#. SVr4 defines an additional error
-#. code EAGAIN. The SVr4 error conditions don't map neatly onto Linux's.
#. type: Plain text
-#: build/C/man2/mprotect.2:116
-msgid ""
-"SVr4, POSIX.1-2001. POSIX says that the behavior of B<mprotect>() is "
-"unspecified if it is applied to a region of memory that was not obtained via "
-"B<mmap>(2)."
+#: build/C/man3/posix_fallocate.3:103
+msgid "B<posix_fallocate>() is available since glibc 2.1.94."
msgstr ""
#. type: Plain text
-#: build/C/man2/mprotect.2:123
-msgid ""
-"On Linux it is always permissible to call B<mprotect>() on any address in a "
-"process's address space (except for the kernel vsyscall area). In "
-"particular it can be used to change existing code mappings to be writable."
+#: build/C/man3/posix_fallocate.3:108
+msgid "The B<posix_fallocate>() function is thread-safe."
msgstr ""
#. type: Plain text
-#: build/C/man2/mprotect.2:133
+#: build/C/man3/posix_fallocate.3:133
msgid ""
-"Whether B<PROT_EXEC> has any effect different from B<PROT_READ> is "
-"architecture- and kernel version-dependent. On some hardware architectures "
-"(e.g., i386), B<PROT_WRITE> implies B<PROT_READ>."
+"POSIX.1-2008 says that an implementation I<shall> give the B<EINVAL> error "
+"if I<len> was 0, or I<offset> was less than 0. POSIX.1-2001 says that an "
+"implementation I<shall> give the B<EINVAL> error if I<len> is less than 0, "
+"or I<offset> was less than 0, and I<may> give the error if I<len> equals "
+"zero."
msgstr ""
#. type: Plain text
-#: build/C/man2/mprotect.2:142
+#: build/C/man3/posix_fallocate.3:138
msgid ""
-"POSIX.1-2001 says that an implementation may permit access other than that "
-"specified in I<prot>, but at a minimum can only allow write access if "
-"B<PROT_WRITE> has been set, and must not allow any access if B<PROT_NONE> "
-"has been set."
+"In the glibc implementation, B<posix_fallocate>() is implemented using "
+"B<fallocate>(2)."
msgstr ""
#. type: Plain text
-#: build/C/man2/mprotect.2:148
-msgid ""
-"The program below allocates four pages of memory, makes the third of these "
-"pages read-only, and then executes a loop that walks upward through the "
-"allocated region modifying bytes."
+#: build/C/man3/posix_fallocate.3:143
+msgid "B<fallocate>(1), B<fallocate>(2), B<lseek>(2), B<posix_fadvise>(2)"
msgstr ""
-#. type: Plain text
-#: build/C/man2/mprotect.2:151
-msgid "An example of what we might see when running the program is the following:"
+#. type: TH
+#: build/C/man3/posix_memalign.3:29
+#, no-wrap
+msgid "POSIX_MEMALIGN"
msgstr ""
-#. type: Plain text
-#: build/C/man2/mprotect.2:157
+#. type: TH
+#: build/C/man3/posix_memalign.3:29
#, no-wrap
-msgid ""
-"$B< ./a.out>\n"
-"Start of region: 0x804c000\n"
-"Got SIGSEGV at address: 0x804e000\n"
+msgid "2013-09-02"
msgstr ""
#. type: Plain text
-#: build/C/man2/mprotect.2:169
-#, no-wrap
+#: build/C/man3/posix_memalign.3:32
msgid ""
-"#include E<lt>unistd.hE<gt>\n"
-"#include E<lt>signal.hE<gt>\n"
-"#include E<lt>stdio.hE<gt>\n"
-"#include E<lt>malloc.hE<gt>\n"
-"#include E<lt>stdlib.hE<gt>\n"
-"#include E<lt>errno.hE<gt>\n"
-"#include E<lt>sys/mman.hE<gt>\n"
+"posix_memalign, aligned_alloc, memalign, valloc, pvalloc - allocate aligned "
+"memory"
msgstr ""
#. type: Plain text
-#: build/C/man2/mprotect.2:174
+#: build/C/man3/posix_memalign.3:35
#, no-wrap
-msgid "char *buffer;\n"
+msgid "B<#include E<lt>stdlib.hE<gt>>\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/mprotect.2:182
+#: build/C/man3/posix_memalign.3:39
#, no-wrap
msgid ""
-"static void\n"
-"handler(int sig, siginfo_t *si, void *unused)\n"
-"{\n"
-" printf(\"Got SIGSEGV at address: 0x%lx\\en\",\n"
-" (long) si-E<gt>si_addr);\n"
-" exit(EXIT_FAILURE);\n"
-"}\n"
+"B<int posix_memalign(void **>I<memptr>B<, size_t >I<alignment>B<, size_t "
+">I<size>B<);>\n"
+"B<void *aligned_alloc(size_t >I<alignment>B<, size_t >I<size>B<);>\n"
+"B<void *valloc(size_t >I<size>B<);>\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/mprotect.2:189
+#: build/C/man3/posix_memalign.3:44
#, no-wrap
msgid ""
-"int\n"
-"main(int argc, char *argv[])\n"
-"{\n"
-" char *p;\n"
-" int pagesize;\n"
-" struct sigaction sa;\n"
+"B<void *memalign(size_t >I<alignment>B<, size_t >I<size>B<);>\n"
+"B<void *pvalloc(size_t >I<size>B<);>\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/mprotect.2:195
-#, no-wrap
+#: build/C/man3/posix_memalign.3:54
msgid ""
-" sa.sa_flags = SA_SIGINFO;\n"
-" sigemptyset(&sa.sa_mask);\n"
-" sa.sa_sigaction = handler;\n"
-" if (sigaction(SIGSEGV, &sa, NULL) == -1)\n"
-" handle_error(\"sigaction\");\n"
+"B<posix_memalign>(): _POSIX_C_SOURCE\\ E<gt>=\\ 200112L || _XOPEN_SOURCE\\ "
+"E<gt>=\\ 600"
msgstr ""
#. type: Plain text
-#: build/C/man2/mprotect.2:199
-#, no-wrap
-msgid ""
-" pagesize = sysconf(_SC_PAGE_SIZE);\n"
-" if (pagesize == -1)\n"
-" handle_error(\"sysconf\");\n"
+#: build/C/man3/posix_memalign.3:57
+msgid "B<aligned_alloc>(): _ISOC11_SOURCE"
msgstr ""
#. type: Plain text
-#: build/C/man2/mprotect.2:202
+#: build/C/man3/posix_memalign.3:59
+msgid "B<valloc>():"
+msgstr ""
+
+#. type: TP
+#: build/C/man3/posix_memalign.3:62
#, no-wrap
-msgid ""
-" /* Allocate a buffer aligned on a page boundary;\n"
-" initial protection is PROT_READ | PROT_WRITE */\n"
+msgid "Since glibc 2.12:"
msgstr ""
#. type: Plain text
-#: build/C/man2/mprotect.2:206
+#: build/C/man3/posix_memalign.3:69
#, no-wrap
msgid ""
-" buffer = memalign(pagesize, 4 * pagesize);\n"
-" if (buffer == NULL)\n"
-" handle_error(\"memalign\");\n"
+"_BSD_SOURCE ||\n"
+" (_XOPEN_SOURCE\\ E<gt>=\\ 500 ||\n"
+" _XOPEN_SOURCE\\ &&\\ _XOPEN_SOURCE_EXTENDED) &&\n"
+" !(_POSIX_C_SOURCE\\ E<gt>=\\ 200112L || _XOPEN_SOURCE\\ E<gt>=\\ 600)\n"
msgstr ""
-#. type: Plain text
-#: build/C/man2/mprotect.2:208
+#. type: TP
+#: build/C/man3/posix_memalign.3:71
#, no-wrap
-msgid " printf(\"Start of region: 0x%lx\\en\", (long) buffer);\n"
+msgid "Before glibc 2.12:"
msgstr ""
#. type: Plain text
-#: build/C/man2/mprotect.2:212
-#, no-wrap
+#: build/C/man3/posix_memalign.3:75
msgid ""
-" if (mprotect(buffer + pagesize * 2, pagesize,\n"
-" PROT_READ) == -1)\n"
-" handle_error(\"mprotect\");\n"
+"_BSD_SOURCE || _XOPEN_SOURCE\\ E<gt>=\\ 500 || _XOPEN_SOURCE\\ &&\\ "
+"_XOPEN_SOURCE_EXTENDED"
msgstr ""
#. type: Plain text
-#: build/C/man2/mprotect.2:215
-#, no-wrap
+#: build/C/man3/posix_memalign.3:82
msgid ""
-" for (p = buffer ; ; )\n"
-" *(p++) = \\(aqa\\(aq;\n"
+"(The (nonstandard) header file I<E<lt>malloc.hE<gt>> also exposes the "
+"declaration of B<valloc>(); no feature test macros are required.)"
msgstr ""
+#. glibc does this:
#. type: Plain text
-#: build/C/man2/mprotect.2:219
-#, no-wrap
+#: build/C/man3/posix_memalign.3:104
msgid ""
-" printf(\"Loop completed\\en\"); /* Should never happen */\n"
-" exit(EXIT_SUCCESS);\n"
-"}\n"
+"The function B<posix_memalign>() allocates I<size> bytes and places the "
+"address of the allocated memory in I<*memptr>. The address of the allocated "
+"memory will be a multiple of I<alignment>, which must be a power of two and "
+"a multiple of I<sizeof(void\\ *)>. If I<size> is 0, then the value placed "
+"in I<*memptr> is either NULL, or a unique pointer value that can later be "
+"successfully passed to B<free>(3)."
msgstr ""
+#. The behavior of memalign() for size==0 is as for posix_memalign()
+#. but no standards govern this.
#. type: Plain text
-#: build/C/man2/mprotect.2:222
-msgid "B<mmap>(2), B<sysconf>(3)"
+#: build/C/man3/posix_memalign.3:115
+msgid ""
+"The obsolete function B<memalign>() allocates I<size> bytes and returns a "
+"pointer to the allocated memory. The memory address will be a multiple of "
+"I<alignment>, which must be a power of two."
msgstr ""
-#. type: TH
-#: build/C/man2/mremap.2:31
-#, no-wrap
-msgid "MREMAP"
+#. type: Plain text
+#: build/C/man3/posix_memalign.3:124
+msgid ""
+"The function B<aligned_alloc>() is the same as B<memalign>(), except for "
+"the added restriction that I<size> should be a multiple of I<alignment>."
msgstr ""
-#. type: TH
-#: build/C/man2/mremap.2:31
-#, no-wrap
-msgid "2010-06-10"
+#. type: Plain text
+#: build/C/man3/posix_memalign.3:133
+msgid ""
+"The obsolete function B<valloc>() allocates I<size> bytes and returns a "
+"pointer to the allocated memory. The memory address will be a multiple of "
+"the page size. It is equivalent to I<memalign(sysconf(_SC_PAGESIZE),size)>."
msgstr ""
#. type: Plain text
-#: build/C/man2/mremap.2:34
-msgid "mremap - remap a virtual memory address"
+#: build/C/man3/posix_memalign.3:140
+msgid ""
+"The obsolete function B<pvalloc>() is similar to B<valloc>(), but rounds "
+"the size of the allocation up to the next multiple of the system page size."
msgstr ""
#. type: Plain text
-#: build/C/man2/mremap.2:37
-#, no-wrap
-msgid "B<#define _GNU_SOURCE> /* See feature_test_macros(7) */\n"
+#: build/C/man3/posix_memalign.3:142
+msgid "For all of these functions, the memory is not zeroed."
msgstr ""
#. type: Plain text
-#: build/C/man2/mremap.2:42
-#, no-wrap
+#: build/C/man3/posix_memalign.3:149
msgid ""
-"B<void *mremap(void *>I<old_address>B<, size_t >I<old_size>B<,>\n"
-"B< size_t >I<new_size>B<, int >I<flags>B<, ... /* void "
-"*>I<new_address>B< */);>\n"
+"B<aligned_alloc>(), B<memalign>(), B<valloc>(), and B<pvalloc>() return a "
+"pointer to the allocated memory, or NULL if the request fails."
msgstr ""
#. type: Plain text
-#: build/C/man2/mremap.2:48
+#: build/C/man3/posix_memalign.3:157
msgid ""
-"B<mremap>() expands (or shrinks) an existing memory mapping, potentially "
-"moving it at the same time (controlled by the I<flags> argument and the "
-"available virtual address space)."
+"B<posix_memalign>() returns zero on success, or one of the error values "
+"listed in the next section on failure. The value of I<errno> is "
+"indeterminate after a call to B<posix_memalign>()."
msgstr ""
#. type: Plain text
-#: build/C/man2/mremap.2:62
+#: build/C/man3/posix_memalign.3:164
msgid ""
-"I<old_address> is the old address of the virtual memory block that you want "
-"to expand (or shrink). Note that I<old_address> has to be page aligned. "
-"I<old_size> is the old size of the virtual memory block. I<new_size> is the "
-"requested size of the virtual memory block after the resize. An optional "
-"fifth argument, I<new_address>, may be provided; see the description of "
-"B<MREMAP_FIXED> below."
+"The I<alignment> argument was not a power of two, or was not a multiple of "
+"I<sizeof(void\\ *)>."
msgstr ""
#. type: Plain text
-#: build/C/man2/mremap.2:74
-msgid ""
-"In Linux the memory is divided into pages. A user process has (one or) "
-"several linear virtual memory segments. Each virtual memory segment has one "
-"or more mappings to real memory pages (in the page table). Each virtual "
-"memory segment has its own protection (access rights), which may cause a "
-"segmentation violation if the memory is accessed incorrectly (e.g., writing "
-"to a read-only segment). Accessing virtual memory outside of the segments "
-"will also cause a segmentation violation."
+#: build/C/man3/posix_memalign.3:167
+msgid "There was insufficient memory to fulfill the allocation request."
msgstr ""
#. type: Plain text
-#: build/C/man2/mremap.2:82
+#: build/C/man3/posix_memalign.3:174
msgid ""
-"B<mremap>() uses the Linux page table scheme. B<mremap>() changes the "
-"mapping between virtual addresses and memory pages. This can be used to "
-"implement a very efficient B<realloc>(3)."
+"The functions B<memalign>(), B<valloc>(), and B<pvalloc>() have been "
+"available in all Linux libc libraries."
msgstr ""
#. type: Plain text
-#: build/C/man2/mremap.2:84
-msgid "The I<flags> bit-mask argument may be 0, or include the following flag:"
+#: build/C/man3/posix_memalign.3:178
+msgid "The function B<aligned_alloc>() was added to glibc in version 2.16."
msgstr ""
-#. type: TP
-#: build/C/man2/mremap.2:84
-#, no-wrap
-msgid "B<MREMAP_MAYMOVE>"
+#. type: Plain text
+#: build/C/man3/posix_memalign.3:182
+msgid "The function B<posix_memalign>() is available since glibc 2.1.91."
msgstr ""
#. type: Plain text
-#: build/C/man2/mremap.2:96
+#: build/C/man3/posix_memalign.3:189
msgid ""
-"By default, if there is not sufficient space to expand a mapping at its "
-"current location, then B<mremap>() fails. If this flag is specified, then "
-"the kernel is permitted to relocate the mapping to a new virtual address, if "
-"necessary. If the mapping is relocated, then absolute pointers into the old "
-"mapping location become invalid (offsets relative to the starting address of "
-"the mapping should be employed)."
+"The function B<valloc>() appeared in 3.0BSD. It is documented as being "
+"obsolete in 4.3BSD, and as legacy in SUSv2. It does not appear in "
+"POSIX.1-2001."
msgstr ""
-#. type: TP
-#: build/C/man2/mremap.2:96
-#, no-wrap
-msgid "B<MREMAP_FIXED> (since Linux 2.3.31)"
+#. type: Plain text
+#: build/C/man3/posix_memalign.3:193
+msgid "The function B<pvalloc>() is a GNU extension."
msgstr ""
#. type: Plain text
-#: build/C/man2/mremap.2:118
-msgid ""
-"This flag serves a similar purpose to the B<MAP_FIXED> flag of B<mmap>(2). "
-"If this flag is specified, then B<mremap>() accepts a fifth argument, "
-"I<void *new_address>, which specifies a page-aligned address to which the "
-"mapping must be moved. Any previous mapping at the address range specified "
-"by I<new_address> and I<new_size> is unmapped. If B<MREMAP_FIXED> is "
-"specified, then B<MREMAP_MAYMOVE> must also be specified."
+#: build/C/man3/posix_memalign.3:197
+msgid "The function B<memalign>() appears in SunOS 4.1.3 but not in 4.4BSD."
msgstr ""
#. type: Plain text
-#: build/C/man2/mremap.2:128
-msgid ""
-"If the memory segment specified by I<old_address> and I<old_size> is locked "
-"(using B<mlock>(2) or similar), then this lock is maintained when the "
-"segment is resized and/or relocated. As a consequence, the amount of memory "
-"locked by the process may change."
+#: build/C/man3/posix_memalign.3:201
+msgid "The function B<posix_memalign>() comes from POSIX.1d."
msgstr ""
#. type: Plain text
-#: build/C/man2/mremap.2:136
-msgid ""
-"On success B<mremap>() returns a pointer to the new virtual memory area. "
-"On error, the value B<MAP_FAILED> (that is, I<(void\\ *)\\ -1>) is returned, "
-"and I<errno> is set appropriately."
+#: build/C/man3/posix_memalign.3:206
+msgid "The function B<aligned_alloc>() is specified in the C11 standard."
+msgstr ""
+
+#. type: SS
+#: build/C/man3/posix_memalign.3:206
+#, no-wrap
+msgid "Headers"
msgstr ""
#. type: Plain text
-#: build/C/man2/mremap.2:143
+#: build/C/man3/posix_memalign.3:210
msgid ""
-"The caller tried to expand a memory segment that is locked, but this was not "
-"possible without exceeding the B<RLIMIT_MEMLOCK> resource limit."
+"Everybody agrees that B<posix_memalign>() is declared in "
+"I<E<lt>stdlib.hE<gt>>."
msgstr ""
#. type: Plain text
-#: build/C/man2/mremap.2:152
+#: build/C/man3/posix_memalign.3:214
msgid ""
-"\"Segmentation fault.\" Some address in the range I<old_address> to "
-"I<old_address>+I<old_size> is an invalid virtual memory address for this "
-"process. You can also get B<EFAULT> even if there exist mappings that cover "
-"the whole address space requested, but those mappings are of different "
-"types."
+"On some systems B<memalign>() is declared in I<E<lt>stdlib.hE<gt>> instead "
+"of I<E<lt>malloc.hE<gt>>."
msgstr ""
#. type: Plain text
-#: build/C/man2/mremap.2:180
+#: build/C/man3/posix_memalign.3:221
msgid ""
-"An invalid argument was given. Possible causes are: I<old_address> was not "
-"page aligned; a value other than B<MREMAP_MAYMOVE> or B<MREMAP_FIXED> was "
-"specified in I<flags>; I<new_size> was zero; I<new_size> or I<new_address> "
-"was invalid; or the new address range specified by I<new_address> and "
-"I<new_size> overlapped the old address range specified by I<old_address> and "
-"I<old_size>; or B<MREMAP_FIXED> was specified without also specifying "
-"B<MREMAP_MAYMOVE>."
+"According to SUSv2, B<valloc>() is declared in I<E<lt>stdlib.hE<gt>>. "
+"Libc4,5 and glibc declare it in I<E<lt>malloc.hE<gt>>, and also in "
+"I<E<lt>stdlib.hE<gt>> if suitable feature test macros are defined (see "
+"above)."
msgstr ""
#. type: Plain text
-#: build/C/man2/mremap.2:186
+#: build/C/man3/posix_memalign.3:230
msgid ""
-"The memory area cannot be expanded at the current virtual address, and the "
-"B<MREMAP_MAYMOVE> flag is not set in I<flags>. Or, there is not enough "
-"(virtual) memory available."
+"On many systems there are alignment restrictions, for example, on buffers "
+"used for direct block device I/O. POSIX specifies the "
+"I<pathconf(path,_PC_REC_XFER_ALIGN)> call that tells what alignment is "
+"needed. Now one can use B<posix_memalign>() to satisfy this requirement."
msgstr ""
-#. 4.2BSD had a (never actually implemented)
-#. .BR mremap (2)
-#. call with completely different semantics.
#. type: Plain text
-#: build/C/man2/mremap.2:192
+#: build/C/man3/posix_memalign.3:239
msgid ""
-"This call is Linux-specific, and should not be used in programs intended to "
-"be portable."
+"B<posix_memalign>() verifies that I<alignment> matches the requirements "
+"detailed above. B<memalign>() may not check that the I<alignment> argument "
+"is correct."
msgstr ""
+#. Other systems allow passing the result of
+#. .IR valloc ()
+#. to
+#. .IR free (3),
+#. but not to
+#. .IR realloc (3).
#. type: Plain text
-#: build/C/man2/mremap.2:200
+#: build/C/man3/posix_memalign.3:267
msgid ""
-"Prior to version 2.4, glibc did not expose the definition of "
-"B<MREMAP_FIXED>, and the prototype for B<mremap>() did not allow for the "
-"I<new_address> argument."
+"POSIX requires that memory obtained from B<posix_memalign>() can be freed "
+"using B<free>(3). Some systems provide no way to reclaim memory allocated "
+"with B<memalign>() or B<valloc>() (because one can pass to B<free>(3) "
+"only a pointer obtained from B<malloc>(3), while, for example, B<memalign>() "
+"would call B<malloc>(3) and then align the obtained value). The glibc "
+"implementation allows memory obtained from any of these functions to be "
+"reclaimed with B<free>(3)."
msgstr ""
#. type: Plain text
-#: build/C/man2/mremap.2:209
+#: build/C/man3/posix_memalign.3:272
msgid ""
-"B<brk>(2), B<getpagesize>(2), B<getrlimit>(2), B<mlock>(2), B<mmap>(2), "
-"B<sbrk>(2), B<malloc>(3), B<realloc>(3)"
+"The glibc B<malloc>(3) always returns 8-byte aligned memory addresses, so "
+"these functions are needed only if you require larger alignment values."
msgstr ""
#. type: Plain text
-#: build/C/man2/mremap.2:213
-msgid ""
-"Your favorite OS text book for more information on paged memory. (I<Modern "
-"Operating Systems> by Andrew S. Tanenbaum, I<Inside Linux> by Randolf "
-"Bentson, I<The Design of the UNIX Operating System> by Maurice J. Bach.)"
+#: build/C/man3/posix_memalign.3:277
+msgid "B<brk>(2), B<getpagesize>(2), B<free>(3), B<malloc>(3)"
msgstr ""
#. type: TH
-#: build/C/man2/msync.2:25
+#: build/C/man2/readahead.2:28
#, no-wrap
-msgid "MSYNC"
+msgid "READAHEAD"
msgstr ""
#. type: TH
-#: build/C/man2/msync.2:25 build/C/man2/remap_file_pages.2:26
+#: build/C/man2/readahead.2:28
#, no-wrap
-msgid "2008-04-22"
-msgstr ""
-
-#. type: Plain text
-#: build/C/man2/msync.2:28
-msgid "msync - synchronize a file with a memory map"
+msgid "2014-03-15"
msgstr ""
#. type: Plain text
-#: build/C/man2/msync.2:32
-msgid "B<int msync(void *>I<addr>B<, size_t >I<length>B<, int >I<flags>B<);>"
+#: build/C/man2/readahead.2:31
+msgid "readahead - initiate file readahead into page cache"
msgstr ""
#. type: Plain text
-#: build/C/man2/msync.2:48
+#: build/C/man2/readahead.2:37
+#, no-wrap
msgid ""
-"B<msync>() flushes changes made to the in-core copy of a file that was "
-"mapped into memory using B<mmap>(2) back to disk. Without use of this call "
-"there is no guarantee that changes are written back before B<munmap>(2) is "
-"called. To be more precise, the part of the file that corresponds to the "
-"memory area starting at I<addr> and having length I<length> is updated."
+"B<ssize_t readahead(int >I<fd>B<, off64_t >I<offset>B<, size_t "
+">I<count>B<);>\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/msync.2:68
+#: build/C/man2/readahead.2:44
msgid ""
-"The I<flags> argument may have the bits B<MS_ASYNC>, B<MS_SYNC>, and "
-"B<MS_INVALIDATE> set, but not both B<MS_ASYNC> and B<MS_SYNC>. B<MS_ASYNC> "
-"specifies that an update be scheduled, but the call returns immediately. "
-"B<MS_SYNC> asks for an update and waits for it to complete. "
-"B<MS_INVALIDATE> asks to invalidate other mappings of the same file (so that "
-"they can be updated with the fresh values just written)."
+"B<readahead>() initiates readahead on a file so that subsequent reads from "
+"that file will be satisfied from the cache, and not block on disk I/O "
+"(assuming the readahead was initiated early enough and that other activity "
+"on the system did not in the meantime flush pages from the cache)."
msgstr ""
#. type: Plain text
-#: build/C/man2/msync.2:73
+#: build/C/man2/readahead.2:66
msgid ""
-"On success, zero is returned. On error, -1 is returned, and I<errno> is set "
-"appropriately."
-msgstr ""
-
-#. type: TP
-#: build/C/man2/msync.2:74
-#, no-wrap
-msgid "B<EBUSY>"
+"The I<fd> argument is a file descriptor identifying the file which is to be "
+"read. The I<offset> argument specifies the starting point from which data "
+"is to be read and I<count> specifies the number of bytes to be read. I/O is "
+"performed in whole pages, so that I<offset> is effectively rounded down to a "
+"page boundary and bytes are read up to the next page boundary greater than "
+"or equal to I<(offset+count)>. B<readahead>() does not read beyond the end "
+"of the file. The current file offset of the open file referred to by I<fd> "
+"is left unchanged."
msgstr ""
#. type: Plain text
-#: build/C/man2/msync.2:80
+#: build/C/man2/readahead.2:72
msgid ""
-"B<MS_INVALIDATE> was specified in I<flags>, and a memory lock exists for the "
-"specified address range."
+"On success, B<readahead>() returns 0; on failure, -1 is returned, with "
+"I<errno> set to indicate the cause of the error."
msgstr ""
#. type: Plain text
-#: build/C/man2/msync.2:93
-msgid ""
-"I<addr> is not a multiple of PAGESIZE; or any bit other than B<MS_ASYNC> | "
-"B<MS_INVALIDATE> | B<MS_SYNC> is set in I<flags>; or both B<MS_SYNC> and "
-"B<MS_ASYNC> are set in I<flags>."
+#: build/C/man2/readahead.2:77
+msgid "I<fd> is not a valid file descriptor or is not open for reading."
msgstr ""
#. type: Plain text
-#: build/C/man2/msync.2:96
-msgid "The indicated memory (or part of it) was not mapped."
+#: build/C/man2/readahead.2:83
+msgid "I<fd> does not refer to a file type to which B<readahead>() can be applied."
msgstr ""
#. type: Plain text
-#: build/C/man2/msync.2:98 build/C/man3/posix_fallocate.3:103 build/C/man3/shm_open.3:251 build/C/man7/shm_overview.7:103
-msgid "POSIX.1-2001."
+#: build/C/man2/readahead.2:88
+msgid ""
+"The B<readahead>() system call appeared in Linux 2.4.13; glibc support has "
+"been provided since version 2.3."
msgstr ""
#. type: Plain text
-#: build/C/man2/msync.2:105
+#: build/C/man2/readahead.2:93
msgid ""
-"This call was introduced in Linux 1.3.21, and then used B<EFAULT> instead of "
-"B<ENOMEM>. In Linux 2.4.19 this was changed to the POSIX value B<ENOMEM>."
+"The B<readahead>() system call is Linux-specific, and its use should be "
+"avoided in portable applications."
msgstr ""
-#. POSIX.1-2001: It shall be defined to -1 or 0 or 200112L.
-#. -1: unavailable, 0: ask using sysconf().
-#. glibc defines them to 1.
#. type: Plain text
-#: build/C/man2/msync.2:118
+#: build/C/man2/readahead.2:98
msgid ""
-"On POSIX systems on which B<msync>() is available, both "
-"B<_POSIX_MAPPED_FILES> and B<_POSIX_SYNCHRONIZED_IO> are defined in "
-"I<E<lt>unistd.hE<gt>> to a value greater than 0. (See also B<sysconf>(3).)"
+"On some 32-bit architectures, the calling signature for this system call "
+"differs, for the reasons described in B<syscall>(2)."
msgstr ""
-#. type: TP
-#: build/C/man2/msync.2:120 build/C/man7/shm_overview.7:46
-#, no-wrap
-msgid "B<mmap>(2)"
+#. type: Plain text
+#: build/C/man2/readahead.2:107
+msgid ""
+"B<readahead>() attempts to schedule the reads in the background and return "
+"immediately. However, it may block while it reads the filesystem metadata "
+"needed to locate the requested blocks. This occurs frequently with ext[234] "
+"on large files using indirect blocks instead of extents, giving the "
+"appearance that the call blocks until the requested data has been read."
msgstr ""
-#. type: TH
-#: build/C/man3/mtrace.3:23
-#, no-wrap
-msgid "MTRACE"
+#. type: Plain text
+#: build/C/man2/readahead.2:113
+msgid "B<lseek>(2), B<madvise>(2), B<mmap>(2), B<posix_fadvise>(2), B<read>(2)"
msgstr ""
#. type: TH
-#: build/C/man3/mtrace.3:23
+#: build/C/man2/remap_file_pages.2:28
#, no-wrap
-msgid "2012-03-22"
+msgid "REMAP_FILE_PAGES"
msgstr ""
#. type: Plain text
-#: build/C/man3/mtrace.3:26
-msgid "mtrace, muntrace - malloc tracing"
+#: build/C/man2/remap_file_pages.2:31
+msgid "remap_file_pages - create a nonlinear file mapping"
msgstr ""
#. type: Plain text
-#: build/C/man3/mtrace.3:28
-msgid "B<#include E<lt>mcheck.hE<gt>>"
+#: build/C/man2/remap_file_pages.2:35
+#, no-wrap
+msgid ""
+"B<#define _GNU_SOURCE> /* See feature_test_macros(7) */\n"
+"B<#include E<lt>sys/mman.hE<gt>>\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/mtrace.3:30
-msgid "B<void mtrace(void);>"
+#: build/C/man2/remap_file_pages.2:38
+#, no-wrap
+msgid ""
+"B<int remap_file_pages(void *>I<addr>B<, size_t >I<size>B<, int "
+">I<prot>B<,>\n"
+"B< size_t >I<pgoff>B<, int >I<flags>B<);>\n"
msgstr ""
+#. commit 33041a0d76d3c3e0aff28ac95a2ffdedf1282dbc
+#. http://lwn.net/Articles/597632/
#. type: Plain text
-#: build/C/man3/mtrace.3:32
-msgid "B<void muntrace(void);>"
+#: build/C/man2/remap_file_pages.2:47
+msgid ""
+"B<Note>: this system call is (since Linux 3.16) deprecated and will "
+"eventually be replaced by a slower in-kernel emulation. Those few "
+"applications that use this system call should consider migrating to "
+"alternatives."
msgstr ""
#. type: Plain text
-#: build/C/man3/mtrace.3:44
+#: build/C/man2/remap_file_pages.2:59
msgid ""
-"The B<mtrace>() function installs hook functions for the memory-allocation "
-"functions (B<malloc>(3), B<realloc>(3) B<memalign>(3), B<free>(3)). These "
-"hook functions record tracing information about memory allocation and "
-"deallocation. The tracing information can be used to discover memory leaks "
-"and attempts to free nonallocated memory in a program."
+"The B<remap_file_pages>() system call is used to create a nonlinear "
+"mapping, that is, a mapping in which the pages of the file are mapped into a "
+"nonsequential order in memory. The advantage of using B<remap_file_pages>() "
+"over using repeated calls to B<mmap>(2) is that the former approach does "
+"not require the kernel to create additional VMA (Virtual Memory Area) data "
+"structures."
msgstr ""
#. type: Plain text
-#: build/C/man3/mtrace.3:55
-msgid ""
-"The B<muntrace>() function disables the hook functions installed by "
-"B<mtrace>(), so that tracing information is no longer recorded for the "
-"memory-allocation functions. If no hook functions were successfully "
-"installed by B<mtrace>(), B<muntrace>() does nothing."
+#: build/C/man2/remap_file_pages.2:61
+msgid "To create a nonlinear mapping we perform the following steps:"
msgstr ""
-#. type: Plain text
-#: build/C/man3/mtrace.3:63
-msgid ""
-"When B<mtrace>(3) is called, it checks the value of the environment "
-"variable B<MALLOC_TRACE>, which should contain the pathname of a file in "
-"which the tracing information is to be recorded. If the pathname is "
-"successfully opened, it is truncated to zero length."
+#. type: IP
+#: build/C/man2/remap_file_pages.2:61 build/C/man2/memfd_create.2:219
+#, no-wrap
+msgid "1."
msgstr ""
#. type: Plain text
-#: build/C/man3/mtrace.3:76
+#: build/C/man2/remap_file_pages.2:69
msgid ""
-"If B<MALLOC_TRACE> is not set, or the pathname it specifies is invalid or "
-"not writable, then no hook functions are installed, and B<mtrace>() has no "
-"effect. In set-user-ID and set-group-ID programs, B<MALLOC_TRACE> is "
-"ignored, and B<mtrace>() has no effect."
+"Use B<mmap>(2) to create a mapping (which is initially linear). This "
+"mapping must be created with the B<MAP_SHARED> flag."
msgstr ""
-#. type: Plain text
-#: build/C/man3/mtrace.3:84
-msgid ""
-"In normal usage, B<mtrace>() is called once at the start of execution of a "
-"program, and B<muntrace>() is never called."
+#. type: IP
+#: build/C/man2/remap_file_pages.2:69 build/C/man2/memfd_create.2:225
+#, no-wrap
+msgid "2."
msgstr ""
#. type: Plain text
-#: build/C/man3/mtrace.3:94
+#: build/C/man2/remap_file_pages.2:77
msgid ""
-"The tracing output produced after a call to B<mtrace>() is textual, but not "
-"designed to be human readable. The GNU C library provides a Perl script, "
-"B<mtrace>(1), that interprets the trace log and produces human-readable "
-"output. For best results, the traced program should be compiled with "
-"debugging enabled, so that line-number information is recorded in the "
-"executable."
+"Use one or more calls to B<remap_file_pages>() to rearrange the "
+"correspondence between the pages of the mapping and the pages of the file. "
+"It is possible to map the same page of a file into multiple locations within "
+"the mapped region."
msgstr ""
#. type: Plain text
-#: build/C/man3/mtrace.3:100
+#: build/C/man2/remap_file_pages.2:88
msgid ""
-"The tracing performed by B<mtrace>() incurs a performance penalty (if "
-"B<MALLOC_TRACE> points to a valid, writable pathname)."
+"The I<pgoff> and I<size> arguments specify the region of the file that is to "
+"be relocated within the mapping: I<pgoff> is a file offset in units of the "
+"system page size; I<size> is the length of the region in bytes."
msgstr ""
#. type: Plain text
-#: build/C/man3/mtrace.3:106
+#: build/C/man2/remap_file_pages.2:106
msgid ""
-"The line-number information produced by B<mtrace>(1) is not always precise: "
-"the line number references may refer to the previous or following "
-"(non-blank) line of the source code."
+"The I<addr> argument serves two purposes. First, it identifies the mapping "
+"whose pages we want to rearrange. Thus, I<addr> must be an address that "
+"falls within a region previously mapped by a call to B<mmap>(2). Second, "
+"I<addr> specifies the address at which the file pages identified by I<pgoff> "
+"and I<size> will be placed."
msgstr ""
+#. This rounding is weird, and not consistent with the treatment of
+#. the analogous arguments for munmap()/mprotect() and for mlock().
+#. MTK, 14 Sep 2005
#. type: Plain text
-#: build/C/man3/mtrace.3:113
+#: build/C/man2/remap_file_pages.2:120
msgid ""
-"The shell session below demonstrates the use of the B<mtrace>() function "
-"and the B<mtrace>(1) command in a program that has memory leaks at two "
-"different locations. The demonstration uses the following program:"
+"The values specified in I<addr> and I<size> should be multiples of the "
+"system page size. If they are not, then the kernel rounds I<both> values "
+"I<down> to the nearest multiple of the page size."
msgstr ""
#. type: Plain text
-#: build/C/man3/mtrace.3:120
-#, no-wrap
-msgid ""
-"$ B<cat t_mtrace.c>\n"
-"#include E<lt>mcheck.hE<gt>\n"
-"#include E<lt>stdlib.hE<gt>\n"
-"#include E<lt>stdio.hE<gt>\n"
+#: build/C/man2/remap_file_pages.2:124
+msgid "The I<prot> argument must be specified as 0."
msgstr ""
#. type: Plain text
-#: build/C/man3/mtrace.3:125
-#, no-wrap
+#: build/C/man2/remap_file_pages.2:132
msgid ""
-"int\n"
-"main(int argc, char *argv[])\n"
-"{\n"
-" int j;\n"
+"The I<flags> argument has the same meaning as for B<mmap>(2), but all flags "
+"other than B<MAP_NONBLOCK> are ignored."
msgstr ""
#. type: Plain text
-#: build/C/man3/mtrace.3:127
-#, no-wrap
-msgid " mtrace();\n"
+#: build/C/man2/remap_file_pages.2:139
+msgid ""
+"On success, B<remap_file_pages>() returns 0. On error, -1 is returned, and "
+"I<errno> is set appropriately."
msgstr ""
#. type: Plain text
-#: build/C/man3/mtrace.3:130
-#, no-wrap
+#: build/C/man2/remap_file_pages.2:147
msgid ""
-" for (j = 0; j E<lt> 2; j++)\n"
-" malloc(100); /* Never freed--a memory leak */\n"
+"I<addr> does not refer to a valid mapping created with the B<MAP_SHARED> "
+"flag."
msgstr ""
+#. And possibly others from vma->vm_ops->populate()
#. type: Plain text
-#: build/C/man3/mtrace.3:134
-#, no-wrap
-msgid ""
-" calloc(16, 16); /* Never freed--a memory leak */\n"
-" exit(EXIT_SUCCESS);\n"
-"}\n"
+#: build/C/man2/remap_file_pages.2:156
+msgid "I<addr>, I<size>, I<prot>, or I<pgoff> is invalid."
msgstr ""
#. type: Plain text
-#: build/C/man3/mtrace.3:140
+#: build/C/man2/remap_file_pages.2:161
msgid ""
-"When we run the program as follows, we see that B<mtrace>() diagnosed "
-"memory leaks at two different locations in the program:"
+"The B<remap_file_pages>() system call appeared in Linux 2.5.46; glibc "
+"support was added in version 2.3.3."
msgstr ""
#. type: Plain text
-#: build/C/man3/mtrace.3:153
-#, no-wrap
-msgid ""
-"$ B<cc -g t_mtrace.c -o t_mtrace>\n"
-"$ B<export MALLOC_TRACE=/tmp/t>\n"
-"$ B<./t_mtrace>\n"
-"$ B<mtrace ./t_mtrace $MALLOC_TRACE>\n"
-"Memory not freed:\n"
-"-----------------\n"
-" Address Size Caller\n"
-"0x084c9378 0x64 at /home/cecilia/t_mtrace.c:12\n"
-"0x084c93e0 0x64 at /home/cecilia/t_mtrace.c:12\n"
-"0x084c9448 0x100 at /home/cecilia/t_mtrace.c:16\n"
+#: build/C/man2/remap_file_pages.2:165
+msgid "The B<remap_file_pages>() system call is Linux-specific."
msgstr ""
+#. commit 3ee6dafc677a68e461a7ddafc94a580ebab80735
#. type: Plain text
-#: build/C/man3/mtrace.3:165
+#: build/C/man2/remap_file_pages.2:176
msgid ""
-"The first two messages about unfreed memory correspond to the two "
-"B<malloc>(3) calls inside the I<for> loop. The final message corresponds "
-"to the call to B<calloc>(3) (which in turn calls B<malloc>(3))."
+"Since Linux 2.6.23, B<remap_file_pages>() creates non-linear mappings only "
+"on in-memory file systems such as tmpfs, hugetlbfs or ramfs. On filesystems "
+"with a backing store, B<remap_file_pages>() is not much more efficient than "
+"using B<mmap>(2) to adjust which parts of the file are mapped to which "
+"addresses."
msgstr ""
#. type: Plain text
-#: build/C/man3/mtrace.3:168
-msgid "B<mtrace>(1), B<malloc>(3), B<malloc_hook>(3)"
+#: build/C/man2/remap_file_pages.2:183
+msgid ""
+"B<getpagesize>(2), B<mmap>(2), B<mmap2>(2), B<mprotect>(2), B<mremap>(2), "
+"B<msync>(2)"
msgstr ""
#. type: TH
-#: build/C/man2/posix_fadvise.2:27
+#: build/C/man3/shm_open.3:26
#, no-wrap
-msgid "POSIX_FADVISE"
+msgid "SHM_OPEN"
msgstr ""
-#. type: TH
-#: build/C/man2/posix_fadvise.2:27 build/C/man2/sync_file_range.2:30
-#, no-wrap
-msgid "2010-10-09"
+#. type: Plain text
+#: build/C/man3/shm_open.3:29
+msgid "shm_open, shm_unlink - create/open or unlink POSIX shared memory objects"
msgstr ""
#. type: Plain text
-#: build/C/man2/posix_fadvise.2:30
-msgid "posix_fadvise - predeclare an access pattern for file data"
+#: build/C/man3/shm_open.3:33
+msgid "B<#include E<lt>sys/stat.hE<gt>> /* For mode constants */"
msgstr ""
#. type: Plain text
-#: build/C/man2/posix_fadvise.2:33 build/C/man3/posix_fallocate.3:29
-#, no-wrap
-msgid "B<#include E<lt>fcntl.hE<gt>>\n"
+#: build/C/man3/shm_open.3:35
+msgid "B<#include E<lt>fcntl.hE<gt>> /* For O_* constants */"
msgstr ""
-#. type: Plain text
-#: build/C/man2/posix_fadvise.2:36
-#, no-wrap
-msgid ""
-"B<int posix_fadvise(int >I<fd>B<, off_t >I<offset>B<, off_t >I<len>B<, int "
-">I<advice>B<);>\n"
+#. type: Plain text
+#: build/C/man3/shm_open.3:37
+msgid "B<int shm_open(const char *>I<name>B<, int >I<oflag>B<, mode_t >I<mode>B<);>"
msgstr ""
#. type: Plain text
-#: build/C/man2/posix_fadvise.2:45
-msgid "B<posix_fadvise>():"
+#: build/C/man3/shm_open.3:39
+msgid "B<int shm_unlink(const char *>I<name>B<);>"
msgstr ""
#. type: Plain text
-#: build/C/man2/posix_fadvise.2:47 build/C/man3/posix_fallocate.3:42
-msgid "_XOPEN_SOURCE\\ E<gt>=\\ 600 || _POSIX_C_SOURCE\\ E<gt>=\\ 200112L"
+#: build/C/man3/shm_open.3:41
+msgid "Link with I<-lrt>."
msgstr ""
#. type: Plain text
-#: build/C/man2/posix_fadvise.2:55
+#: build/C/man3/shm_open.3:53
msgid ""
-"Programs can use B<posix_fadvise>() to announce an intention to access file "
-"data in a specific pattern in the future, thus allowing the kernel to "
-"perform appropriate optimizations."
+"B<shm_open>() creates and opens a new, or opens an existing, POSIX shared "
+"memory object. A POSIX shared memory object is in effect a handle which can "
+"be used by unrelated processes to B<mmap>(2) the same region of shared "
+"memory. The B<shm_unlink>() function performs the converse operation, "
+"removing an object previously created by B<shm_open>()."
msgstr ""
+#. glibc allows the initial slash to be omitted, and makes
+#. multiple initial slashes equivalent to a single slash.
+#. This differs from the implementation of POSIX message queues.
+#. glibc allows subdirectory components in the name, in which
+#. case the subdirectory must exist under /dev/shm, and allow the
+#. required permissions if a user wants to create a shared memory
+#. object in that subdirectory.
#. type: Plain text
-#: build/C/man2/posix_fadvise.2:62
+#: build/C/man3/shm_open.3:74
msgid ""
-"The I<advice> applies to a (not necessarily existent) region starting at "
-"I<offset> and extending for I<len> bytes (or until the end of the file if "
-"I<len> is 0) within the file referred to by I<fd>. The I<advice> is not "
-"binding; it merely constitutes an expectation on behalf of the application."
+"The operation of B<shm_open>() is analogous to that of B<open>(2). I<name> "
+"specifies the shared memory object to be created or opened. For portable "
+"use, a shared memory object should be identified by a name of the form "
+"I</somename>; that is, a null-terminated string of up to B<NAME_MAX> (i.e., "
+"255) characters consisting of an initial slash, followed by one or more "
+"characters, none of which are slashes."
msgstr ""
#. type: Plain text
-#: build/C/man2/posix_fadvise.2:64
-msgid "Permissible values for I<advice> include:"
+#: build/C/man3/shm_open.3:81
+msgid ""
+"I<oflag> is a bit mask created by ORing together exactly one of B<O_RDONLY> "
+"or B<O_RDWR> and any of the other flags listed here:"
msgstr ""
#. type: TP
-#: build/C/man2/posix_fadvise.2:64
+#: build/C/man3/shm_open.3:81
#, no-wrap
-msgid "B<POSIX_FADV_NORMAL>"
+msgid "B<O_RDONLY>"
msgstr ""
#. type: Plain text
-#: build/C/man2/posix_fadvise.2:70
+#: build/C/man3/shm_open.3:89
msgid ""
-"Indicates that the application has no advice to give about its access "
-"pattern for the specified data. If no advice is given for an open file, "
-"this is the default assumption."
+"Open the object for read access. A shared memory object opened in this way "
+"can be B<mmap>(2)ed only for read (B<PROT_READ>) access."
msgstr ""
#. type: TP
-#: build/C/man2/posix_fadvise.2:70
+#: build/C/man3/shm_open.3:89
#, no-wrap
-msgid "B<POSIX_FADV_SEQUENTIAL>"
+msgid "B<O_RDWR>"
msgstr ""
#. type: Plain text
-#: build/C/man2/posix_fadvise.2:74
-msgid ""
-"The application expects to access the specified data sequentially (with "
-"lower offsets read before higher ones)."
+#: build/C/man3/shm_open.3:92
+msgid "Open the object for read-write access."
msgstr ""
#. type: TP
-#: build/C/man2/posix_fadvise.2:74
+#: build/C/man3/shm_open.3:92
#, no-wrap
-msgid "B<POSIX_FADV_RANDOM>"
+msgid "B<O_CREAT>"
msgstr ""
+#. In truth it is actually the filesystem IDs on Linux, but these
+#. are nearly always the same as the effective IDs. (MTK, Jul 05)
#. type: Plain text
-#: build/C/man2/posix_fadvise.2:77
-msgid "The specified data will be accessed in random order."
-msgstr ""
-
-#. type: TP
-#: build/C/man2/posix_fadvise.2:77
-#, no-wrap
-msgid "B<POSIX_FADV_NOREUSE>"
+#: build/C/man3/shm_open.3:112
+msgid ""
+"Create the shared memory object if it does not exist. The user and group "
+"ownership of the object are taken from the corresponding effective IDs of "
+"the calling process, and the object's permission bits are set according to "
+"the low-order 9 bits of I<mode>, except that those bits set in the process "
+"file mode creation mask (see B<umask>(2)) are cleared for the new object. "
+"A set of macro constants which can be used to define I<mode> is listed in "
+"B<open>(2). (Symbolic definitions of these constants can be obtained by "
+"including I<E<lt>sys/stat.hE<gt>>.)"
msgstr ""
#. type: Plain text
-#: build/C/man2/posix_fadvise.2:80
-msgid "The specified data will be accessed only once."
+#: build/C/man3/shm_open.3:118
+msgid ""
+"A new shared memory object initially has zero length\\(emthe size of the "
+"object can be set using B<ftruncate>(2). The newly allocated bytes of a "
+"shared memory object are automatically initialized to 0."
msgstr ""
#. type: TP
-#: build/C/man2/posix_fadvise.2:80
+#: build/C/man3/shm_open.3:118
#, no-wrap
-msgid "B<POSIX_FADV_WILLNEED>"
+msgid "B<O_EXCL>"
msgstr ""
#. type: Plain text
-#: build/C/man2/posix_fadvise.2:83
-msgid "The specified data will be accessed in the near future."
+#: build/C/man3/shm_open.3:127
+msgid ""
+"If B<O_CREAT> was also specified, and a shared memory object with the given "
+"I<name> already exists, return an error. The check for the existence of the "
+"object, and its creation if it does not exist, are performed atomically."
msgstr ""
#. type: TP
-#: build/C/man2/posix_fadvise.2:83
+#: build/C/man3/shm_open.3:127
#, no-wrap
-msgid "B<POSIX_FADV_DONTNEED>"
+msgid "B<O_TRUNC>"
msgstr ""
#. type: Plain text
-#: build/C/man2/posix_fadvise.2:86
-msgid "The specified data will not be accessed in the near future."
+#: build/C/man3/shm_open.3:130
+msgid "If the shared memory object already exists, truncate it to zero bytes."
msgstr ""
#. type: Plain text
-#: build/C/man2/posix_fadvise.2:89
-msgid "On success, zero is returned. On error, an error number is returned."
+#: build/C/man3/shm_open.3:133
+msgid ""
+"Definitions of these flag values can be obtained by including "
+"I<E<lt>fcntl.hE<gt>>."
msgstr ""
#. type: Plain text
-#: build/C/man2/posix_fadvise.2:93
-msgid "The I<fd> argument was not a valid file descriptor."
+#: build/C/man3/shm_open.3:144
+msgid ""
+"On successful completion B<shm_open>() returns a new file descriptor "
+"referring to the shared memory object. This file descriptor is guaranteed "
+"to be the lowest-numbered file descriptor not previously opened within the "
+"process. The B<FD_CLOEXEC> flag (see B<fcntl>(2)) is set for the file "
+"descriptor."
msgstr ""
#. type: Plain text
-#: build/C/man2/posix_fadvise.2:96
-msgid "An invalid value was specified for I<advice>."
+#: build/C/man3/shm_open.3:153
+msgid ""
+"The file descriptor is normally used in subsequent calls to B<ftruncate>(2) "
+"(for a newly created object) and B<mmap>(2). After a call to B<mmap>(2) "
+"the file descriptor may be closed without affecting the memory mapping."
msgstr ""
#. type: Plain text
-#: build/C/man2/posix_fadvise.2:103
+#: build/C/man3/shm_open.3:171
msgid ""
-"The specified file descriptor refers to a pipe or FIFO. (Linux actually "
-"returns B<EINVAL> in this case.)"
+"The operation of B<shm_unlink>() is analogous to B<unlink>(2): it removes a "
+"shared memory object name, and, once all processes have unmapped the object, "
+"de-allocates and destroys the contents of the associated memory region. "
+"After a successful B<shm_unlink>(), attempts to B<shm_open>() an object "
+"with the same I<name> will fail (unless B<O_CREAT> was specified, in which "
+"case a new, distinct object is created)."
msgstr ""
-#. of fadvise64_64()
#. type: Plain text
-#: build/C/man2/posix_fadvise.2:111
+#: build/C/man3/shm_open.3:180
msgid ""
-"Kernel support first appeared in Linux 2.5.60; the underlying system call is "
-"called B<fadvise64>(). Library support has been provided since glibc "
-"version 2.2, via the wrapper function B<posix_fadvise>()."
+"On success, B<shm_open>() returns a nonnegative file descriptor. On "
+"failure, B<shm_open>() returns -1. B<shm_unlink>() returns 0 on success, "
+"or -1 on error."
msgstr ""
#. type: Plain text
-#: build/C/man2/posix_fadvise.2:120
+#: build/C/man3/shm_open.3:187
msgid ""
-"POSIX.1-2001. Note that the type of the I<len> argument was changed from "
-"I<size_t> to I<off_t> in POSIX.1-2003 TC1."
+"On failure, I<errno> is set to indicate the cause of the error. Values "
+"which may appear in I<errno> include the following:"
msgstr ""
#. type: Plain text
-#: build/C/man2/posix_fadvise.2:126
-msgid ""
-"Under Linux, B<POSIX_FADV_NORMAL> sets the readahead window to the default "
-"size for the backing device; B<POSIX_FADV_SEQUENTIAL> doubles this size, and "
-"B<POSIX_FADV_RANDOM> disables file readahead entirely. These changes affect "
-"the entire file, not just the specified region (but other open file handles "
-"to the same file are unaffected)."
+#: build/C/man3/shm_open.3:192
+msgid "Permission to B<shm_unlink>() the shared memory object was denied."
msgstr ""
#. type: Plain text
-#: build/C/man2/posix_fadvise.2:133
+#: build/C/man3/shm_open.3:202
msgid ""
-"B<POSIX_FADV_WILLNEED> initiates a nonblocking read of the specified region "
-"into the page cache. The amount of data read may be decreased by the kernel "
-"depending on virtual memory load. (A few megabytes will usually be fully "
-"satisfied, and more is rarely useful.)"
+"Permission was denied to B<shm_open>() I<name> in the specified I<mode>, or "
+"B<O_TRUNC> was specified and the caller does not have write permission on "
+"the object."
msgstr ""
-#. type: Plain text
-#: build/C/man2/posix_fadvise.2:137
-msgid ""
-"In kernels before 2.6.18, B<POSIX_FADV_NOREUSE> had the same semantics as "
-"B<POSIX_FADV_WILLNEED>. This was probably a bug; since kernel 2.6.18, this "
-"flag is a no-op."
+#. type: TP
+#: build/C/man3/shm_open.3:202 build/C/man2/shmget.2:198
+#, no-wrap
+msgid "B<EEXIST>"
msgstr ""
#. type: Plain text
-#: build/C/man2/posix_fadvise.2:145
+#: build/C/man3/shm_open.3:213
msgid ""
-"B<POSIX_FADV_DONTNEED> attempts to free cached pages associated with the "
-"specified region. This is useful, for example, while streaming large "
-"files. A program may periodically request the kernel to free cached data "
-"that has already been used, so that more useful cached pages are not "
-"discarded instead."
+"Both B<O_CREAT> and B<O_EXCL> were specified to B<shm_open>() and the "
+"shared memory object specified by I<name> already exists."
msgstr ""
#. type: Plain text
-#: build/C/man2/posix_fadvise.2:153
-msgid ""
-"Pages that have not yet been written out will be unaffected, so if the "
-"application wishes to guarantee that pages will be released, it should call "
-"B<fsync>(2) or B<fdatasync>(2) first."
+#: build/C/man3/shm_open.3:220
+msgid "The I<name> argument to B<shm_open>() was invalid."
msgstr ""
-#. type: SS
-#: build/C/man2/posix_fadvise.2:153
+#. type: TP
+#: build/C/man3/shm_open.3:220 build/C/man2/memfd_create.2:146
#, no-wrap
-msgid "arm_fadvise()"
+msgid "B<EMFILE>"
msgstr ""
#. type: Plain text
-#: build/C/man2/posix_fadvise.2:165
-msgid ""
-"The ARM architecture needs 64-bit arguments to be aligned in a suitable pair "
-"of registers. On this architecture, the call signature of "
-"B<posix_fadvise>() is flawed, since it forces a register to be wasted as "
-"padding between the I<fd> and I<len> arguments. Therefore, since Linux "
-"2.6.14, ARM defines a different system call that orders the arguments "
-"suitably:"
+#: build/C/man3/shm_open.3:223
+msgid "The process already has the maximum number of files open."
msgstr ""
-#. type: Plain text
-#: build/C/man2/posix_fadvise.2:170
+#. type: TP
+#: build/C/man3/shm_open.3:223
#, no-wrap
-msgid ""
-"B<long arm_fadvise64_64(int >I<fd>B<, int >I<advice>B<,>\n"
-"B< loff_t >I<offset>B<, loff_t >I<len>B<);>\n"
-msgstr ""
-
-#. No ARM support in glibc.
-#. type: Plain text
-#: build/C/man2/posix_fadvise.2:177
-msgid ""
-"The behavior of this system call is otherwise exactly the same as "
-"B<posix_fadvise>(). No library support is provided for this system call in "
-"glibc."
+msgid "B<ENAMETOOLONG>"
msgstr ""
#. type: Plain text
-#: build/C/man2/posix_fadvise.2:182
-msgid ""
-"In kernels before 2.6.6, if I<len> was specified as 0, then this was "
-"interpreted literally as \"zero bytes\", rather than as meaning \"all bytes "
-"through to the end of the file\"."
+#: build/C/man3/shm_open.3:229
+msgid "The length of I<name> exceeds B<PATH_MAX>."
msgstr ""
#. type: Plain text
-#: build/C/man2/posix_fadvise.2:186
-msgid ""
-"B<readahead>(2), B<sync_file_range>(2), B<posix_fallocate>(3), "
-"B<posix_madvise>(3)"
+#: build/C/man3/shm_open.3:233
+msgid "The limit on the total number of files open on the system has been reached."
msgstr ""
-#. type: TH
-#: build/C/man3/posix_fallocate.3:23
+#. type: TP
+#: build/C/man3/shm_open.3:233 build/C/man3/shm_open.3:242 build/C/man2/shmget.2:225
#, no-wrap
-msgid "POSIX_FALLOCATE"
+msgid "B<ENOENT>"
msgstr ""
-#. type: TH
-#: build/C/man3/posix_fallocate.3:23
-#, no-wrap
-msgid "2010-09-20"
+#. type: Plain text
+#: build/C/man3/shm_open.3:242
+msgid ""
+"An attempt was made to B<shm_open>() a I<name> that did not exist, and "
+"B<O_CREAT> was not specified."
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_fallocate.3:26
-msgid "posix_fallocate - allocate file space"
+#: build/C/man3/shm_open.3:249
+msgid "An attempt was to made to B<shm_unlink>() a I<name> that does not exist."
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_fallocate.3:31
-#, no-wrap
-msgid "B<int posix_fallocate(int >I<fd>B<, off_t >I<offset>B<, off_t >I<len>B<);>\n"
+#: build/C/man3/shm_open.3:251
+msgid "These functions are provided in glibc 2.2 and later."
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_fallocate.3:40
-msgid "B<posix_fallocate>():"
+#: build/C/man3/shm_open.3:257
+msgid ""
+"POSIX.1-2001 says that the group ownership of a newly created shared memory "
+"object is set to either the calling process's effective group ID or \"a "
+"system default group ID\"."
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_fallocate.3:59
+#: build/C/man3/shm_open.3:266
msgid ""
-"The function B<posix_fallocate>() ensures that disk space is allocated for "
-"the file referred to by the descriptor I<fd> for the bytes in the range "
-"starting at I<offset> and continuing for I<len> bytes. After a successful "
-"call to B<posix_fallocate>(), subsequent writes to bytes in the specified "
-"range are guaranteed not to fail because of lack of disk space."
+"POSIX leaves the behavior of the combination of B<O_RDONLY> and B<O_TRUNC> "
+"unspecified. On Linux, this will successfully truncate an existing shared "
+"memory object\\(emthis may not be so on other UNIX systems."
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_fallocate.3:64
+#: build/C/man3/shm_open.3:271
msgid ""
-"If the size of the file is less than I<offset>+I<len>, then the file is "
-"increased to this size; otherwise the file size is left unchanged."
+"The POSIX shared memory object implementation on Linux 2.4 makes use of a "
+"dedicated filesystem, which is normally mounted under I</dev/shm>."
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_fallocate.3:70
+#: build/C/man3/shm_open.3:283
msgid ""
-"B<posix_fallocate>() returns zero on success, or an error number on "
-"failure. Note that I<errno> is not set."
+"B<close>(2), B<fchmod>(2), B<fchown>(2), B<fcntl>(2), B<fstat>(2), "
+"B<ftruncate>(2), B<memfd_create>(2), B<mmap>(2), B<open>(2), B<umask>(2), "
+"B<shm_overview>(7)"
+msgstr ""
+
+#. type: TH
+#: build/C/man7/shm_overview.7:27
+#, no-wrap
+msgid "SHM_OVERVIEW"
+msgstr ""
+
+#. type: TH
+#: build/C/man7/shm_overview.7:27
+#, no-wrap
+msgid "2010-09-10"
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_fallocate.3:79
-msgid "I<offset+len> exceeds the maximum file size."
+#: build/C/man7/shm_overview.7:30
+msgid "shm_overview - overview of POSIX shared memory"
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_fallocate.3:89
-msgid "I<fd> does not refer to a regular file."
+#: build/C/man7/shm_overview.7:33
+msgid ""
+"The POSIX shared memory API allows processes to communicate information by "
+"sharing a region of memory."
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_fallocate.3:98
-msgid "I<fd> refers to a pipe."
+#: build/C/man7/shm_overview.7:35
+msgid "The interfaces employed in the API are:"
+msgstr ""
+
+#. type: TP
+#: build/C/man7/shm_overview.7:35
+#, no-wrap
+msgid "B<shm_open>(3)"
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_fallocate.3:101
-msgid "B<posix_fallocate>() is available since glibc 2.1.94."
+#: build/C/man7/shm_overview.7:42
+msgid ""
+"Create and open a new object, or open an existing object. This is analogous "
+"to B<open>(2). The call returns a file descriptor for use by the other "
+"interfaces listed below."
+msgstr ""
+
+#. type: TP
+#: build/C/man7/shm_overview.7:42
+#, no-wrap
+msgid "B<ftruncate>(2)"
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_fallocate.3:126
+#: build/C/man7/shm_overview.7:46
msgid ""
-"POSIX.1-2008 says that an implementation I<shall> give the B<EINVAL> error "
-"if I<len> was 0, or I<offset> was less than 0. POSIX.1-2001 says that an "
-"implementation I<shall> give the B<EINVAL> error if I<len> is less than 0, "
-"or I<offset> was less than 0, and I<may> give the error if I<len> equals "
-"zero."
+"Set the size of the shared memory object. (A newly created shared memory "
+"object has a length of zero.)"
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_fallocate.3:129
-msgid "B<fallocate>(2), B<lseek>(2), B<posix_fadvise>(2)"
-msgstr ""
-
-#. type: TH
-#: build/C/man3/posix_memalign.3:28
-#, no-wrap
-msgid "POSIX_MEMALIGN"
+#: build/C/man7/shm_overview.7:50
+msgid ""
+"Map the shared memory object into the virtual address space of the calling "
+"process."
msgstr ""
-#. type: TH
-#: build/C/man3/posix_memalign.3:28
+#. type: TP
+#: build/C/man7/shm_overview.7:50
#, no-wrap
-msgid "2012-03-23"
+msgid "B<munmap>(2)"
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_memalign.3:31
+#: build/C/man7/shm_overview.7:54
msgid ""
-"posix_memalign, aligned_alloc, memalign, valloc, pvalloc - Allocate aligned "
-"memory"
+"Unmap the shared memory object from the virtual address space of the calling "
+"process."
msgstr ""
-#. type: Plain text
-#: build/C/man3/posix_memalign.3:34
+#. type: TP
+#: build/C/man7/shm_overview.7:54
#, no-wrap
-msgid "B<#include E<lt>stdlib.hE<gt>>\n"
+msgid "B<shm_unlink>(3)"
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_memalign.3:38
-#, no-wrap
-msgid ""
-"B<int posix_memalign(void **>I<memptr>B<, size_t >I<alignment>B<, size_t "
-">I<size>B<);>\n"
-"B<void *aligned_alloc(size_t >I<alignment>B<, size_t >I<size>B<);>\n"
-"B<void *valloc(size_t >I<size>B<);>\n"
+#: build/C/man7/shm_overview.7:57
+msgid "Remove a shared memory object name."
msgstr ""
-#. type: Plain text
-#: build/C/man3/posix_memalign.3:43
+#. type: TP
+#: build/C/man7/shm_overview.7:57
#, no-wrap
-msgid ""
-"B<void *memalign(size_t >I<alignment>B<, size_t >I<size>B<);>\n"
-"B<void *pvalloc(size_t >I<size>B<);>\n"
+msgid "B<close>(2)"
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_memalign.3:53
+#: build/C/man7/shm_overview.7:62
msgid ""
-"B<posix_memalign>(): _POSIX_C_SOURCE\\ E<gt>=\\ 200112L || _XOPEN_SOURCE\\ "
-"E<gt>=\\ 600"
+"Close the file descriptor allocated by B<shm_open>(3) when it is no longer "
+"needed."
msgstr ""
-#. type: Plain text
-#: build/C/man3/posix_memalign.3:56
-msgid "B<aligned_alloc>(): _ISOC11_SOURCE"
+#. type: TP
+#: build/C/man7/shm_overview.7:62
+#, no-wrap
+msgid "B<fstat>(2)"
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_memalign.3:58
-msgid "B<valloc>():"
+#: build/C/man7/shm_overview.7:76
+msgid ""
+"Obtain a I<stat> structure that describes the shared memory object. Among "
+"the information returned by this call are the object's size (I<st_size>), "
+"permissions (I<st_mode>), owner (I<st_uid>), and group (I<st_gid>)."
msgstr ""
#. type: TP
-#: build/C/man3/posix_memalign.3:61
+#: build/C/man7/shm_overview.7:76
#, no-wrap
-msgid "Since glibc 2.12:"
+msgid "B<fchown>(2)"
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_memalign.3:68
-#, no-wrap
-msgid ""
-"_BSD_SOURCE ||\n"
-" (_XOPEN_SOURCE\\ E<gt>=\\ 500 ||\n"
-" _XOPEN_SOURCE\\ &&\\ _XOPEN_SOURCE_EXTENDED) &&\n"
-" !(_POSIX_C_SOURCE\\ E<gt>=\\ 200112L || _XOPEN_SOURCE\\ E<gt>=\\ 600)\n"
+#: build/C/man7/shm_overview.7:79
+msgid "To change the ownership of a shared memory object."
msgstr ""
#. type: TP
-#: build/C/man3/posix_memalign.3:70
+#: build/C/man7/shm_overview.7:79
#, no-wrap
-msgid "Before glibc 2.12:"
+msgid "B<fchmod>(2)"
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_memalign.3:74
-msgid ""
-"_BSD_SOURCE || _XOPEN_SOURCE\\ E<gt>=\\ 500 || _XOPEN_SOURCE\\ &&\\ "
-"_XOPEN_SOURCE_EXTENDED"
+#: build/C/man7/shm_overview.7:82
+msgid "To change the permissions of a shared memory object."
msgstr ""
-#. type: Plain text
-#: build/C/man3/posix_memalign.3:81
-msgid ""
-"(The (nonstandard) header file I<E<lt>malloc.hE<gt>> also exposes the "
-"declaration of B<valloc>(); no feature test macros are required.)"
+#. type: SS
+#: build/C/man7/shm_overview.7:82
+#, no-wrap
+msgid "Versions"
msgstr ""
-#. glibc does this:
#. type: Plain text
-#: build/C/man3/posix_memalign.3:102
-msgid ""
-"The function B<posix_memalign>() allocates I<size> bytes and places the "
-"address of the allocated memory in I<*memptr>. The address of the allocated "
-"memory will be a multiple of I<alignment>, which must be a power of two and "
-"a multiple of I<sizeof(void *)>. If I<size> is 0, then B<posix_memalign>() "
-"returns either NULL, or a unique pointer value that can later be "
-"successfully passed to B<free>(3)."
+#: build/C/man7/shm_overview.7:84
+msgid "POSIX shared memory is supported since Linux 2.4 and glibc 2.2."
msgstr ""
-#. The behavior of memalign() for size==0 is as for posix_memalign()
-#. but no standards govern this.
-#. type: Plain text
-#: build/C/man3/posix_memalign.3:113
-msgid ""
-"The obsolete function B<memalign>() allocates I<size> bytes and returns a "
-"pointer to the allocated memory. The memory address will be a multiple of "
-"I<alignment>, which must be a power of two."
+#. type: SS
+#: build/C/man7/shm_overview.7:84
+#, no-wrap
+msgid "Persistence"
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_memalign.3:122
+#: build/C/man7/shm_overview.7:89
msgid ""
-"The function B<aligned_alloc>() is the same as B<memalign>(), except for "
-"the added restriction that I<size> should be a multiple of I<alignment>."
+"POSIX shared memory objects have kernel persistence: a shared memory object "
+"will exist until the system is shut down, or until all processes have "
+"unmapped the object and it has been deleted with B<shm_unlink>(3)"
msgstr ""
-#. type: Plain text
-#: build/C/man3/posix_memalign.3:132
-msgid ""
-"The obsolete function B<valloc>() allocates I<size> bytes and returns a "
-"pointer to the allocated memory. The memory address will be a multiple of "
-"the page size. It is equivalent to I<memalign(sysconf(_SC_PAGESIZE),size)>."
+#. type: SS
+#: build/C/man7/shm_overview.7:89
+#, no-wrap
+msgid "Linking"
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_memalign.3:139
+#: build/C/man7/shm_overview.7:94
msgid ""
-"The obsolete function B<pvalloc>() is similar to B<valloc>(), but rounds "
-"the size of the allocation up to the next multiple of the system page size."
+"Programs using the POSIX shared memory API must be compiled with I<cc -lrt> "
+"to link against the real-time library, I<librt>."
msgstr ""
-#. type: Plain text
-#: build/C/man3/posix_memalign.3:141
-msgid "For all of these functions, the memory is not zeroed."
+#. type: SS
+#: build/C/man7/shm_overview.7:94
+#, no-wrap
+msgid "Accessing shared memory objects via the filesystem"
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_memalign.3:148
+#: build/C/man7/shm_overview.7:101
msgid ""
-"B<aligned_alloc>(), B<memalign>(), B<valloc>(), and B<pvalloc>() return a "
-"pointer to the allocated memory, or NULL if the request fails."
+"On Linux, shared memory objects are created in a (I<tmpfs>) virtual "
+"filesystem, normally mounted under I</dev/shm>. Since kernel 2.6.19, Linux "
+"supports the use of access control lists (ACLs) to control the permissions "
+"of objects in the virtual filesystem."
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_memalign.3:155
+#: build/C/man7/shm_overview.7:106
msgid ""
-"B<posix_memalign>() returns zero on success, or one of the error values "
-"listed in the next section on failure. Note that I<errno> is not set."
+"Typically, processes must synchronize their access to a shared memory "
+"object, using, for example, POSIX semaphores."
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_memalign.3:162
+#: build/C/man7/shm_overview.7:114
msgid ""
-"The I<alignment> argument was not a power of two, or was not a multiple of "
-"I<sizeof(void *)>."
-msgstr ""
-
-#. type: Plain text
-#: build/C/man3/posix_memalign.3:165
-msgid "There was insufficient memory to fulfill the allocation request."
+"System V shared memory (B<shmget>(2), B<shmop>(2), etc.) is an older shared "
+"memory API. POSIX shared memory provides a simpler, and better designed "
+"interface; on the other hand POSIX shared memory is somewhat less widely "
+"available (especially on older systems) than System V shared memory."
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_memalign.3:172
+#: build/C/man7/shm_overview.7:127
msgid ""
-"The functions B<memalign>(), B<valloc>(), and B<pvalloc>() have been "
-"available in all Linux libc libraries."
+"B<fchmod>(2), B<fchown>(2), B<fstat>(2), B<ftruncate>(2), B<mmap>(2), "
+"B<mprotect>(2), B<munmap>(2), B<shmget>(2), B<shmop>(2), B<shm_open>(3), "
+"B<shm_unlink>(3), B<sem_overview>(7)"
msgstr ""
-#. type: Plain text
-#: build/C/man3/posix_memalign.3:176
-msgid "The function B<aligned_alloc>() was added to glibc in version 2.16."
+#. type: TH
+#: build/C/man2/shmctl.2:45
+#, no-wrap
+msgid "SHMCTL"
msgstr ""
-#. type: Plain text
-#: build/C/man3/posix_memalign.3:180
-msgid "The function B<posix_memalign>() is available since glibc 2.1.91."
+#. type: TH
+#: build/C/man2/shmctl.2:45
+#, no-wrap
+msgid "2014-02-07"
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_memalign.3:187
-msgid ""
-"The function B<valloc>() appeared in 3.0BSD. It is documented as being "
-"obsolete in 4.3BSD, and as legacy in SUSv2. It does not appear in "
-"POSIX.1-2001."
+#: build/C/man2/shmctl.2:48
+msgid "shmctl - System V shared memory control"
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_memalign.3:191
-msgid "The function B<pvalloc>() is a GNU extension."
+#: build/C/man2/shmctl.2:51 build/C/man2/shmget.2:44
+msgid "B<#include E<lt>sys/ipc.hE<gt>>"
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_memalign.3:195
-msgid "The function B<memalign>() appears in SunOS 4.1.3 but not in 4.4BSD."
+#: build/C/man2/shmctl.2:53 build/C/man2/shmget.2:46
+msgid "B<#include E<lt>sys/shm.hE<gt>>"
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_memalign.3:199
-msgid "The function B<posix_memalign>() comes from POSIX.1d."
+#: build/C/man2/shmctl.2:55
+msgid "B<int shmctl(int >I<shmid>B<, int >I<cmd>B<, struct shmid_ds *>I<buf>B<);>"
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_memalign.3:204
-msgid "The function I<aligned_alloc ()> is specified in the C11 standard."
-msgstr ""
-
-#. type: SS
-#: build/C/man3/posix_memalign.3:204
-#, no-wrap
-msgid "Headers"
+#: build/C/man2/shmctl.2:62
+msgid ""
+"B<shmctl>() performs the control operation specified by I<cmd> on the "
+"System\\ V shared memory segment whose identifier is given in I<shmid>."
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_memalign.3:208
+#: build/C/man2/shmctl.2:67
msgid ""
-"Everybody agrees that B<posix_memalign>() is declared in "
-"I<E<lt>stdlib.hE<gt>>."
+"The I<buf> argument is a pointer to a I<shmid_ds> structure, defined in "
+"I<E<lt>sys/shm.hE<gt>> as follows:"
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_memalign.3:212
+#: build/C/man2/shmctl.2:81
+#, no-wrap
msgid ""
-"On some systems B<memalign>() is declared in I<E<lt>stdlib.hE<gt>> instead "
-"of I<E<lt>malloc.hE<gt>>."
+"struct shmid_ds {\n"
+" struct ipc_perm shm_perm; /* Ownership and permissions */\n"
+" size_t shm_segsz; /* Size of segment (bytes) */\n"
+" time_t shm_atime; /* Last attach time */\n"
+" time_t shm_dtime; /* Last detach time */\n"
+" time_t shm_ctime; /* Last change time */\n"
+" pid_t shm_cpid; /* PID of creator */\n"
+" pid_t shm_lpid; /* PID of last shmat(2)/shmdt(2) */\n"
+" shmatt_t shm_nattch; /* No. of current attaches */\n"
+" ...\n"
+"};\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_memalign.3:219
+#: build/C/man2/shmctl.2:89
msgid ""
-"According to SUSv2, B<valloc>() is declared in I<E<lt>stdlib.hE<gt>>. "
-"Libc4,5 and glibc declare it in I<E<lt>malloc.hE<gt>>, and also in "
-"I<E<lt>stdlib.hE<gt>> if suitable feature test macros are defined (see "
-"above)."
+"The I<ipc_perm> structure is defined as follows (the highlighted fields are "
+"settable using B<IPC_SET>):"
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_memalign.3:228
+#: build/C/man2/shmctl.2:102
+#, no-wrap
msgid ""
-"On many systems there are alignment restrictions, for example, on buffers "
-"used for direct block device I/O. POSIX specifies the "
-"I<pathconf(path,_PC_REC_XFER_ALIGN)> call that tells what alignment is "
-"needed. Now one can use B<posix_memalign>() to satisfy this requirement."
+"struct ipc_perm {\n"
+" key_t __key; /* Key supplied to shmget(2) */\n"
+" uid_t B<uid>; /* Effective UID of owner */\n"
+" gid_t B<gid>; /* Effective GID of owner */\n"
+" uid_t cuid; /* Effective UID of creator */\n"
+" gid_t cgid; /* Effective GID of creator */\n"
+" unsigned short B<mode>; /* B<Permissions> + SHM_DEST and\n"
+" SHM_LOCKED flags */\n"
+" unsigned short __seq; /* Sequence number */\n"
+"};\n"
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_memalign.3:237
-msgid ""
-"B<posix_memalign>() verifies that I<alignment> matches the requirements "
-"detailed above. B<memalign>() may not check that the I<alignment> argument "
-"is correct."
+#: build/C/man2/shmctl.2:108
+msgid "Valid values for I<cmd> are:"
msgstr ""
-#. Other systems allow passing the result of
-#. .IR valloc ()
-#. to
-#. .IR free (3),
-#. but not to
-#. .IR realloc (3).
-#. type: Plain text
-#: build/C/man3/posix_memalign.3:265
-msgid ""
-"POSIX requires that memory obtained from B<posix_memalign>() can be freed "
-"using B<free>(3). Some systems provide no way to reclaim memory allocated "
-"with B<memalign>() or B<valloc>() (because one can only pass to B<free>(3) "
-"a pointer gotten from B<malloc>(3), while, for example, B<memalign>() would "
-"call B<malloc>(3) and then align the obtained value). The glibc "
-"implementation allows memory obtained from any of these these functions to "
-"be reclaimed with B<free>(3)."
+#. type: TP
+#: build/C/man2/shmctl.2:109
+#, no-wrap
+msgid "B<IPC_STAT>"
msgstr ""
#. type: Plain text
-#: build/C/man3/posix_memalign.3:270
+#: build/C/man2/shmctl.2:118
msgid ""
-"The glibc B<malloc>(3) always returns 8-byte aligned memory addresses, so "
-"these functions are only needed if you require larger alignment values."
+"Copy information from the kernel data structure associated with I<shmid> "
+"into the I<shmid_ds> structure pointed to by I<buf>. The caller must have "
+"read permission on the shared memory segment."
msgstr ""
-#. type: Plain text
-#: build/C/man3/posix_memalign.3:274
-msgid "B<brk>(2), B<getpagesize>(2), B<free>(3), B<malloc>(3)"
+#. type: TP
+#: build/C/man2/shmctl.2:118
+#, no-wrap
+msgid "B<IPC_SET>"
msgstr ""
-#. type: TH
-#: build/C/man2/readahead.2:28
-#, no-wrap
-msgid "READAHEAD"
+#. type: Plain text
+#: build/C/man2/shmctl.2:136
+msgid ""
+"Write the values of some members of the I<shmid_ds> structure pointed to by "
+"I<buf> to the kernel data structure associated with this shared memory "
+"segment, updating also its I<shm_ctime> member. The following fields can be "
+"changed: I<shm_perm.uid>, I<shm_perm.gid>, and (the least significant 9 bits "
+"of) I<shm_perm.mode>. The effective UID of the calling process must match "
+"the owner (I<shm_perm.uid>) or creator (I<shm_perm.cuid>) of the shared "
+"memory segment, or the caller must be privileged."
msgstr ""
-#. type: TH
-#: build/C/man2/readahead.2:28 build/C/man7/shm_overview.7:27
+#. type: TP
+#: build/C/man2/shmctl.2:136
#, no-wrap
-msgid "2010-09-10"
-msgstr ""
-
-#. type: Plain text
-#: build/C/man2/readahead.2:31
-msgid "readahead - perform file readahead into page cache"
+msgid "B<IPC_RMID>"
msgstr ""
#. type: Plain text
-#: build/C/man2/readahead.2:37
-#, no-wrap
+#: build/C/man2/shmctl.2:149
msgid ""
-"B<ssize_t readahead(int >I<fd>B<, off64_t >I<offset>B<, size_t "
-">I<count>B<);>\n"
+"Mark the segment to be destroyed. The segment will actually be destroyed "
+"only after the last process detaches it (i.e., when the I<shm_nattch> member "
+"of the associated structure I<shmid_ds> is zero). The caller must be the "
+"owner or creator of the segment, or be privileged. The I<buf> argument is "
+"ignored."
msgstr ""
#. type: Plain text
-#: build/C/man2/readahead.2:65
+#: build/C/man2/shmctl.2:157
msgid ""
-"B<readahead>() populates the page cache with data from a file so that "
-"subsequent reads from that file will not block on disk I/O. The I<fd> "
-"argument is a file descriptor identifying the file which is to be read. The "
-"I<offset> argument specifies the starting point from which data is to be "
-"read and I<count> specifies the number of bytes to be read. I/O is "
-"performed in whole pages, so that I<offset> is effectively rounded down to a "
-"page boundary and bytes are read up to the next page boundary greater than "
-"or equal to I<(offset+count)>. B<readahead>() does not read beyond the end "
-"of the file. B<readahead>() blocks until the specified data has been "
-"read. The current file offset of the open file referred to by I<fd> is left "
-"unchanged."
+"If a segment has been marked for destruction, then the (nonstandard) "
+"B<SHM_DEST> flag of the I<shm_perm.mode> field in the associated data "
+"structure retrieved by B<IPC_STAT> will be set."
msgstr ""
#. type: Plain text
-#: build/C/man2/readahead.2:71
+#: build/C/man2/shmctl.2:160
msgid ""
-"On success, B<readahead>() returns 0; on failure, -1 is returned, with "
-"I<errno> set to indicate the cause of the error."
+"The caller I<must> ensure that a segment is eventually destroyed; otherwise "
+"its pages that were faulted in will remain in memory or swap."
msgstr ""
#. type: Plain text
-#: build/C/man2/readahead.2:76
-msgid "I<fd> is not a valid file descriptor or is not open for reading."
+#: build/C/man2/shmctl.2:165
+msgid ""
+"See also the description of I</proc/sys/kernel/shm_rmid_forced> in "
+"B<proc>(5)."
msgstr ""
-#. type: Plain text
-#: build/C/man2/readahead.2:82
-msgid "I<fd> does not refer to a file type to which B<readahead>() can be applied."
+#. type: TP
+#: build/C/man2/shmctl.2:165
+#, no-wrap
+msgid "B<IPC_INFO> (Linux-specific)"
msgstr ""
#. type: Plain text
-#: build/C/man2/readahead.2:87
+#: build/C/man2/shmctl.2:178
msgid ""
-"The B<readahead>() system call appeared in Linux 2.4.13; glibc support has "
-"been provided since version 2.3."
+"Return information about system-wide shared memory limits and parameters in "
+"the structure pointed to by I<buf>. This structure is of type I<shminfo> "
+"(thus, a cast is required), defined in I<E<lt>sys/shm.hE<gt>> if the "
+"B<_GNU_SOURCE> feature test macro is defined:"
msgstr ""
#. type: Plain text
-#: build/C/man2/readahead.2:92
+#: build/C/man2/shmctl.2:192
+#, no-wrap
msgid ""
-"The B<readahead>() system call is Linux-specific, and its use should be "
-"avoided in portable applications."
+"struct shminfo {\n"
+" unsigned long shmmax; /* Maximum segment size */\n"
+" unsigned long shmmin; /* Minimum segment size;\n"
+" always 1 */\n"
+" unsigned long shmmni; /* Maximum number of segments */\n"
+" unsigned long shmseg; /* Maximum number of segments\n"
+" that a process can attach;\n"
+" unused within kernel */\n"
+" unsigned long shmall; /* Maximum number of pages of\n"
+" shared memory, system-wide */\n"
+"};\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/readahead.2:97
-msgid "B<lseek>(2), B<madvise>(2), B<mmap>(2), B<posix_fadvise>(2), B<read>(2)"
+#: build/C/man2/shmctl.2:205
+msgid ""
+"The I<shmmni>, I<shmmax>, and I<shmall> settings can be changed via I</proc> "
+"files of the same name; see B<proc>(5) for details."
msgstr ""
-#. type: TH
-#: build/C/man2/remap_file_pages.2:26
+#. type: TP
+#: build/C/man2/shmctl.2:205
#, no-wrap
-msgid "REMAP_FILE_PAGES"
+msgid "B<SHM_INFO> (Linux-specific)"
msgstr ""
#. type: Plain text
-#: build/C/man2/remap_file_pages.2:29
-msgid "remap_file_pages - create a nonlinear file mapping"
+#: build/C/man2/shmctl.2:216
+msgid ""
+"Return a I<shm_info> structure whose fields contain information about system "
+"resources consumed by shared memory. This structure is defined in "
+"I<E<lt>sys/shm.hE<gt>> if the B<_GNU_SOURCE> feature test macro is defined:"
msgstr ""
#. type: Plain text
-#: build/C/man2/remap_file_pages.2:33
+#: build/C/man2/shmctl.2:233
#, no-wrap
msgid ""
-"B<#define _GNU_SOURCE> /* See feature_test_macros(7) */\n"
-"B<#include E<lt>sys/mman.hE<gt>>\n"
+"struct shm_info {\n"
+" int used_ids; /* # of currently existing\n"
+" segments */\n"
+" unsigned long shm_tot; /* Total number of shared\n"
+" memory pages */\n"
+" unsigned long shm_rss; /* # of resident shared\n"
+" memory pages */\n"
+" unsigned long shm_swp; /* # of swapped shared\n"
+" memory pages */\n"
+" unsigned long swap_attempts;\n"
+" /* Unused since Linux 2.4 */\n"
+" unsigned long swap_successes;\n"
+" /* Unused since Linux 2.4 */\n"
+"};\n"
msgstr ""
-#. type: Plain text
-#: build/C/man2/remap_file_pages.2:36
+#. type: TP
+#: build/C/man2/shmctl.2:235
#, no-wrap
-msgid ""
-"B<int remap_file_pages(void *>I<addr>B<, size_t >I<size>B<, int "
-">I<prot>B<,>\n"
-"B< ssize_t >I<pgoff>B<, int >I<flags>B<);>\n"
+msgid "B<SHM_STAT> (Linux-specific)"
msgstr ""
#. type: Plain text
-#: build/C/man2/remap_file_pages.2:49
+#: build/C/man2/shmctl.2:246
msgid ""
-"The B<remap_file_pages>() system call is used to create a nonlinear "
-"mapping, that is, a mapping in which the pages of the file are mapped into a "
-"nonsequential order in memory. The advantage of using B<remap_file_pages>() "
-"over using repeated calls to B<mmap>(2) is that the former approach does "
-"not require the kernel to create additional VMA (Virtual Memory Area) data "
-"structures."
+"Return a I<shmid_ds> structure as for B<IPC_STAT>. However, the I<shmid> "
+"argument is not a segment identifier, but instead an index into the kernel's "
+"internal array that maintains information about all shared memory segments "
+"on the system."
msgstr ""
#. type: Plain text
-#: build/C/man2/remap_file_pages.2:51
-msgid "To create a nonlinear mapping we perform the following steps:"
+#: build/C/man2/shmctl.2:249
+msgid ""
+"The caller can prevent or allow swapping of a shared memory segment with the "
+"following I<cmd> values:"
msgstr ""
#. type: TP
-#: build/C/man2/remap_file_pages.2:51
+#: build/C/man2/shmctl.2:250
#, no-wrap
-msgid "1."
+msgid "B<SHM_LOCK> (Linux-specific)"
msgstr ""
#. type: Plain text
-#: build/C/man2/remap_file_pages.2:59
+#: build/C/man2/shmctl.2:262
msgid ""
-"Use B<mmap>(2) to create a mapping (which is initially linear). This "
-"mapping must be created with the B<MAP_SHARED> flag."
+"Prevent swapping of the shared memory segment. The caller must fault in any "
+"pages that are required to be present after locking is enabled. If a "
+"segment has been locked, then the (nonstandard) B<SHM_LOCKED> flag of the "
+"I<shm_perm.mode> field in the associated data structure retrieved by "
+"B<IPC_STAT> will be set."
msgstr ""
#. type: TP
-#: build/C/man2/remap_file_pages.2:59
+#: build/C/man2/shmctl.2:262
#, no-wrap
-msgid "2."
-msgstr ""
-
-#. type: Plain text
-#: build/C/man2/remap_file_pages.2:67
-msgid ""
-"Use one or more calls to B<remap_file_pages>() to rearrange the "
-"correspondence between the pages of the mapping and the pages of the file. "
-"It is possible to map the same page of a file into multiple locations within "
-"the mapped region."
+msgid "B<SHM_UNLOCK> (Linux-specific)"
msgstr ""
#. type: Plain text
-#: build/C/man2/remap_file_pages.2:78
-msgid ""
-"The I<pgoff> and I<size> arguments specify the region of the file that is to "
-"be relocated within the mapping: I<pgoff> is a file offset in units of the "
-"system page size; I<size> is the length of the region in bytes."
+#: build/C/man2/shmctl.2:265
+msgid "Unlock the segment, allowing it to be swapped out."
msgstr ""
+#. There was some weirdness in 2.6.9: SHM_LOCK and SHM_UNLOCK could
+#. be applied to a segment, regardless of ownership of the segment.
+#. This was a botch-up in the move to RLIMIT_MEMLOCK, and was fixed
+#. in 2.6.10. MTK, May 2005
#. type: Plain text
-#: build/C/man2/remap_file_pages.2:96
+#: build/C/man2/shmctl.2:283
msgid ""
-"The I<addr> argument serves two purposes. First, it identifies the mapping "
-"whose pages we want to rearrange. Thus, I<addr> must be an address that "
-"falls within a region previously mapped by a call to B<mmap>(2). Second, "
-"I<addr> specifies the address at which the file pages identified by I<pgoff> "
-"and I<size> will be placed."
+"In kernels before 2.6.10, only a privileged process could employ B<SHM_LOCK> "
+"and B<SHM_UNLOCK>. Since kernel 2.6.10, an unprivileged process can employ "
+"these operations if its effective UID matches the owner or creator UID of "
+"the segment, and (for B<SHM_LOCK>) the amount of memory to be locked falls "
+"within the B<RLIMIT_MEMLOCK> resource limit (see B<setrlimit>(2))."
msgstr ""
-#. This rounding is weird, and not consistent with the treatment of
-#. the analogous arguments for munmap()/mprotect() and for mlock().
-#. MTK, 14 Sep 2005
#. type: Plain text
-#: build/C/man2/remap_file_pages.2:110
+#: build/C/man2/shmctl.2:301
msgid ""
-"The values specified in I<addr> and I<size> should be multiples of the "
-"system page size. If they are not, then the kernel rounds I<both> values "
-"I<down> to the nearest multiple of the page size."
+"A successful B<IPC_INFO> or B<SHM_INFO> operation returns the index of the "
+"highest used entry in the kernel's internal array recording information "
+"about all shared memory segments. (This information can be used with "
+"repeated B<SHM_STAT> operations to obtain information about all shared "
+"memory segments on the system.) A successful B<SHM_STAT> operation returns "
+"the identifier of the shared memory segment whose index was given in "
+"I<shmid>. Other operations return 0 on success."
msgstr ""
#. type: Plain text
-#: build/C/man2/remap_file_pages.2:114
-msgid "The I<prot> argument must be specified as 0."
+#: build/C/man2/shmctl.2:305
+msgid "On error, -1 is returned, and I<errno> is set appropriately."
msgstr ""
#. type: Plain text
-#: build/C/man2/remap_file_pages.2:122
+#: build/C/man2/shmctl.2:314
msgid ""
-"The I<flags> argument has the same meaning as for B<mmap>(2), but all flags "
-"other than B<MAP_NONBLOCK> are ignored."
+"B<IPC_STAT> or B<SHM_STAT> is requested and I<shm_perm.mode> does not allow "
+"read access for I<shmid>, and the calling process does not have the "
+"B<CAP_IPC_OWNER> capability."
msgstr ""
#. type: Plain text
-#: build/C/man2/remap_file_pages.2:129
+#: build/C/man2/shmctl.2:325
msgid ""
-"On success, B<remap_file_pages>() returns 0. On error, -1 is returned, and "
-"I<errno> is set appropriately."
+"The argument I<cmd> has value B<IPC_SET> or B<IPC_STAT> but the address "
+"pointed to by I<buf> isn't accessible."
msgstr ""
-#. type: Plain text
-#: build/C/man2/remap_file_pages.2:137
-msgid ""
-"I<addr> does not refer to a valid mapping created with the B<MAP_SHARED> "
-"flag."
+#. type: TP
+#: build/C/man2/shmctl.2:325 build/C/man2/shmop.2:194
+#, no-wrap
+msgid "B<EIDRM>"
msgstr ""
-#. And possibly others from vma->vm_ops->populate()
#. type: Plain text
-#: build/C/man2/remap_file_pages.2:146
-msgid "I<addr>, I<size>, I<prot>, or I<pgoff> is invalid."
+#: build/C/man2/shmctl.2:328 build/C/man2/shmop.2:197
+msgid "I<shmid> points to a removed identifier."
msgstr ""
#. type: Plain text
-#: build/C/man2/remap_file_pages.2:151
+#: build/C/man2/shmctl.2:337
msgid ""
-"The B<remap_file_pages>() system call appeared in Linux 2.5.46; glibc "
-"support was added in version 2.3.3."
-msgstr ""
-
-#. type: Plain text
-#: build/C/man2/remap_file_pages.2:155
-msgid "The B<remap_file_pages>() system call is Linux-specific."
+"I<shmid> is not a valid identifier, or I<cmd> is not a valid command. Or: "
+"for a B<SHM_STAT> operation, the index value specified in I<shmid> referred "
+"to an array slot that is currently unused."
msgstr ""
#. type: Plain text
-#: build/C/man2/remap_file_pages.2:161
+#: build/C/man2/shmctl.2:348
msgid ""
-"B<getpagesize>(2), B<mmap>(2), B<mmap2>(2), B<mprotect>(2), B<mremap>(2), "
-"B<msync>(2)"
-msgstr ""
-
-#. type: TH
-#: build/C/man3/shm_open.3:26
-#, no-wrap
-msgid "SHM_OPEN"
-msgstr ""
-
-#. type: TH
-#: build/C/man3/shm_open.3:26
-#, no-wrap
-msgid "2009-02-25"
+"(In kernels since 2.6.9), B<SHM_LOCK> was specified and the size of the "
+"to-be-locked segment would mean that the total bytes in locked shared memory "
+"segments would exceed the limit for the real user ID of the calling "
+"process. This limit is defined by the B<RLIMIT_MEMLOCK> soft resource limit "
+"(see B<setrlimit>(2))."
msgstr ""
#. type: Plain text
-#: build/C/man3/shm_open.3:29
-msgid "shm_open, shm_unlink - Create/open or unlink POSIX shared memory objects"
+#: build/C/man2/shmctl.2:353
+msgid ""
+"B<IPC_STAT> is attempted, and the GID or UID value is too large to be stored "
+"in the structure pointed to by I<buf>."
msgstr ""
#. type: Plain text
-#: build/C/man3/shm_open.3:33
-msgid "B<#include E<lt>sys/stat.hE<gt>> /* For mode constants */"
+#: build/C/man2/shmctl.2:365
+msgid ""
+"B<IPC_SET> or B<IPC_RMID> is attempted, and the effective user ID of the "
+"calling process is not that of the creator (found in I<shm_perm.cuid>), or "
+"the owner (found in I<shm_perm.uid>), and the process was not privileged "
+"(Linux: did not have the B<CAP_SYS_ADMIN> capability)."
msgstr ""
#. type: Plain text
-#: build/C/man3/shm_open.3:35
-msgid "B<#include E<lt>fcntl.hE<gt>> /* For O_* constants */"
+#: build/C/man2/shmctl.2:377
+msgid ""
+"Or (in kernels before 2.6.9), B<SHM_LOCK> or B<SHM_UNLOCK> was specified, "
+"but the process was not privileged (Linux: did not have the B<CAP_IPC_LOCK> "
+"capability). (Since Linux 2.6.9, this error can also occur if the "
+"B<RLIMIT_MEMLOCK> is 0 and the caller is not privileged.)"
msgstr ""
+#. SVr4 documents an additional error condition EMFILE.
#. type: Plain text
-#: build/C/man3/shm_open.3:37
-msgid "B<int shm_open(const char *>I<name>B<, int >I<oflag>B<, mode_t >I<mode>B<);>"
+#: build/C/man2/shmctl.2:382 build/C/man2/shmget.2:251 build/C/man2/shmop.2:231
+msgid "SVr4, POSIX.1-2001."
msgstr ""
+#. Like Linux, the FreeBSD man pages still document
+#. the inclusion of these header files.
#. type: Plain text
-#: build/C/man3/shm_open.3:39
-msgid "B<int shm_unlink(const char *>I<name>B<);>"
+#: build/C/man2/shmctl.2:395 build/C/man2/shmget.2:269
+msgid ""
+"The inclusion of I<E<lt>sys/types.hE<gt>> and I<E<lt>sys/ipc.hE<gt>> isn't "
+"required on Linux or by any version of POSIX. However, some old "
+"implementations required the inclusion of these header files, and the SVID "
+"also documented their inclusion. Applications intended to be portable to "
+"such old systems may need to include these header files."
msgstr ""
#. type: Plain text
-#: build/C/man3/shm_open.3:41
-msgid "Link with I<-lrt>."
+#: build/C/man2/shmctl.2:407
+msgid ""
+"The B<IPC_INFO>, B<SHM_STAT> and B<SHM_INFO> operations are used by the "
+"B<ipcs>(1) program to provide information on allocated resources. In the "
+"future, these may modified or moved to a I</proc> filesystem interface."
msgstr ""
#. type: Plain text
-#: build/C/man3/shm_open.3:53
+#: build/C/man2/shmctl.2:415
msgid ""
-"B<shm_open>() creates and opens a new, or opens an existing, POSIX shared "
-"memory object. A POSIX shared memory object is in effect a handle which can "
-"be used by unrelated processes to B<mmap>(2) the same region of shared "
-"memory. The B<shm_unlink>() function performs the converse operation, "
-"removing an object previously created by B<shm_open>()."
+"Linux permits a process to attach (B<shmat>(2)) a shared memory segment "
+"that has already been marked for deletion using I<shmctl(IPC_RMID)>. This "
+"feature is not available on other UNIX implementations; portable "
+"applications should avoid relying on it."
msgstr ""
-#. glibc allows the initial slash to be omitted, and makes
-#. multiple initial slashes equivalent to a single slash.
-#. This differs from the implementation of POSIX message queues.
-#. glibc allows subdirectory components in the name, in which
-#. case the subdirectory must exist under /dev/shm, and allow the
-#. required permissions if a user wants to create a shared memory
-#. object in that subdirectory.
#. type: Plain text
-#: build/C/man3/shm_open.3:74
-msgid ""
-"The operation of B<shm_open>() is analogous to that of B<open>(2). I<name> "
-"specifies the shared memory object to be created or opened. For portable "
-"use, a shared memory object should be identified by a name of the form "
-"I</somename>; that is, a null-terminated string of up to B<NAME_MAX> (i.e., "
-"255) characters consisting of an initial slash, followed by one or more "
-"characters, none of which are slashes."
+#: build/C/man2/shmctl.2:428
+msgid ""
+"Various fields in a I<struct shmid_ds> were typed as I<short> under Linux "
+"2.2 and have become I<long> under Linux 2.4. To take advantage of this, a "
+"recompilation under glibc-2.1.91 or later should suffice. (The kernel "
+"distinguishes old and new calls by an B<IPC_64> flag in I<cmd>.)"
msgstr ""
#. type: Plain text
-#: build/C/man3/shm_open.3:81
+#: build/C/man2/shmctl.2:435
msgid ""
-"I<oflag> is a bit mask created by ORing together exactly one of B<O_RDONLY> "
-"or B<O_RDWR> and any of the other flags listed here:"
+"B<mlock>(2), B<setrlimit>(2), B<shmget>(2), B<shmop>(2), B<capabilities>(7), "
+"B<svipc>(7)"
msgstr ""
-#. type: TP
-#: build/C/man3/shm_open.3:81
+#. type: TH
+#: build/C/man2/shmget.2:38
#, no-wrap
-msgid "B<O_RDONLY>"
-msgstr ""
-
-#. type: Plain text
-#: build/C/man3/shm_open.3:87
-msgid ""
-"Open the object for read access. A shared memory object opened in this way "
-"can only be B<mmap>(2)ed for read (B<PROT_READ>) access."
+msgid "SHMGET"
msgstr ""
-#. type: TP
-#: build/C/man3/shm_open.3:87
+#. type: TH
+#: build/C/man2/shmget.2:38
#, no-wrap
-msgid "B<O_RDWR>"
+msgid "2015-01-10"
msgstr ""
#. type: Plain text
-#: build/C/man3/shm_open.3:90
-msgid "Open the object for read-write access."
+#: build/C/man2/shmget.2:41
+msgid "shmget - allocates a System V shared memory segment"
msgstr ""
-#. type: TP
-#: build/C/man3/shm_open.3:90
-#, no-wrap
-msgid "B<O_CREAT>"
+#. type: Plain text
+#: build/C/man2/shmget.2:48
+msgid "B<int shmget(key_t >I<key>B<, size_t >I<size>B<, int >I<shmflg>B<);>"
msgstr ""
-#. In truth it is actually the file system IDs on Linux, but these
-#. are nearly always the same as the effective IDs. (MTK, Jul 05)
#. type: Plain text
-#: build/C/man3/shm_open.3:110
+#: build/C/man2/shmget.2:72
msgid ""
-"Create the shared memory object if it does not exist. The user and group "
-"ownership of the object are taken from the corresponding effective IDs of "
-"the calling process, and the object's permission bits are set according to "
-"the low-order 9 bits of I<mode>, except that those bits set in the process "
-"file mode creation mask (see B<umask>(2)) are cleared for the new object. "
-"A set of macro constants which can be used to define I<mode> is listed in "
-"B<open>(2). (Symbolic definitions of these constants can be obtained by "
-"including I<E<lt>sys/stat.hE<gt>>.)"
+"B<shmget>() returns the identifier of the System\\ V shared memory segment "
+"associated with the value of the argument I<key>. A new shared memory "
+"segment, with size equal to the value of I<size> rounded up to a multiple of "
+"B<PAGE_SIZE>, is created if I<key> has the value B<IPC_PRIVATE> or I<key> "
+"isn't B<IPC_PRIVATE>, no shared memory segment corresponding to I<key> "
+"exists, and B<IPC_CREAT> is specified in I<shmflg>."
msgstr ""
#. type: Plain text
-#: build/C/man3/shm_open.3:116
+#: build/C/man2/shmget.2:91
msgid ""
-"A new shared memory object initially has zero length\\(emthe size of the "
-"object can be set using B<ftruncate>(2). The newly allocated bytes of a "
-"shared memory object are automatically initialized to 0."
+"If I<shmflg> specifies both B<IPC_CREAT> and B<IPC_EXCL> and a shared memory "
+"segment already exists for I<key>, then B<shmget>() fails with I<errno> set "
+"to B<EEXIST>. (This is analogous to the effect of the combination B<O_CREAT "
+"| O_EXCL> for B<open>(2).)"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/shmget.2:95
+msgid "The value I<shmflg> is composed of:"
msgstr ""
#. type: TP
-#: build/C/man3/shm_open.3:116
+#: build/C/man2/shmget.2:95
#, no-wrap
-msgid "B<O_EXCL>"
+msgid "B<IPC_CREAT>"
msgstr ""
#. type: Plain text
-#: build/C/man3/shm_open.3:125
+#: build/C/man2/shmget.2:102
msgid ""
-"If B<O_CREAT> was also specified, and a shared memory object with the given "
-"I<name> already exists, return an error. The check for the existence of the "
-"object, and its creation if it does not exist, are performed atomically."
+"Create a new segment. If this flag is not used, then B<shmget>() will find "
+"the segment associated with I<key> and check to see if the user has "
+"permission to access the segment."
msgstr ""
#. type: TP
-#: build/C/man3/shm_open.3:125
+#: build/C/man2/shmget.2:102
#, no-wrap
-msgid "B<O_TRUNC>"
+msgid "B<IPC_EXCL>"
msgstr ""
#. type: Plain text
-#: build/C/man3/shm_open.3:128
-msgid "If the shared memory object already exists, truncate it to zero bytes."
+#: build/C/man2/shmget.2:108
+msgid ""
+"This flag is used with B<IPC_CREAT> to ensure that this call creates the "
+"segment. If the segment already exists, the call fails."
msgstr ""
-#. type: Plain text
-#: build/C/man3/shm_open.3:131
-msgid ""
-"Definitions of these flag values can be obtained by including "
-"I<E<lt>fcntl.hE<gt>>."
+#. type: TP
+#: build/C/man2/shmget.2:108
+#, no-wrap
+msgid "B<SHM_HUGETLB> (since Linux 2.6)"
msgstr ""
#. type: Plain text
-#: build/C/man3/shm_open.3:142
+#: build/C/man2/shmget.2:114
msgid ""
-"On successful completion B<shm_open>() returns a new file descriptor "
-"referring to the shared memory object. This file descriptor is guaranteed "
-"to be the lowest-numbered file descriptor not previously opened within the "
-"process. The B<FD_CLOEXEC> flag (see B<fcntl>(2)) is set for the file "
-"descriptor."
+"Allocate the segment using \"huge pages.\" See the Linux kernel source file "
+"I<Documentation/vm/hugetlbpage.txt> for further information."
msgstr ""
-#. type: Plain text
-#: build/C/man3/shm_open.3:151
-msgid ""
-"The file descriptor is normally used in subsequent calls to B<ftruncate>(2) "
-"(for a newly created object) and B<mmap>(2). After a call to B<mmap>(2) "
-"the file descriptor may be closed without affecting the memory mapping."
+#. type: TP
+#: build/C/man2/shmget.2:114
+#, no-wrap
+msgid "B<SHM_NORESERVE> (since Linux 2.6.15)"
msgstr ""
+#. As at 2.6.17-rc2, this flag has no effect if SHM_HUGETLB was also
+#. specified.
#. type: Plain text
-#: build/C/man3/shm_open.3:169
+#: build/C/man2/shmget.2:133
msgid ""
-"The operation of B<shm_unlink>() is analogous to B<unlink>(2): it removes a "
-"shared memory object name, and, once all processes have unmapped the object, "
-"de-allocates and destroys the contents of the associated memory region. "
-"After a successful B<shm_unlink>(), attempts to B<shm_open>() an object "
-"with the same I<name> will fail (unless B<O_CREAT> was specified, in which "
-"case a new, distinct object is created)."
+"This flag serves the same purpose as the B<mmap>(2) B<MAP_NORESERVE> flag. "
+"Do not reserve swap space for this segment. When swap space is reserved, "
+"one has the guarantee that it is possible to modify the segment. When swap "
+"space is not reserved one might get B<SIGSEGV> upon a write if no physical "
+"memory is available. See also the discussion of the file "
+"I</proc/sys/vm/overcommit_memory> in B<proc>(5)."
msgstr ""
#. type: Plain text
-#: build/C/man3/shm_open.3:178
+#: build/C/man2/shmget.2:143
msgid ""
-"On success, B<shm_open>() returns a nonnegative file descriptor. On "
-"failure, B<shm_open>() returns -1. B<shm_unlink>() returns 0 on success, "
-"or -1 on error."
+"In addition to the above flags, the least significant 9 bits of I<shmflg> "
+"specify the permissions granted to the owner, group, and others. These bits "
+"have the same format, and the same meaning, as the I<mode> argument of "
+"B<open>(2). Presently, execute permissions are not used by the system."
msgstr ""
#. type: Plain text
-#: build/C/man3/shm_open.3:185
+#: build/C/man2/shmget.2:151
msgid ""
-"On failure, I<errno> is set to indicate the cause of the error. Values "
-"which may appear in I<errno> include the following:"
+"When a new shared memory segment is created, its contents are initialized to "
+"zero values, and its associated data structure, I<shmid_ds> (see "
+"B<shmctl>(2)), is initialized as follows:"
msgstr ""
#. type: Plain text
-#: build/C/man3/shm_open.3:190
-msgid "Permission to B<shm_unlink>() the shared memory object was denied."
+#: build/C/man2/shmget.2:156
+msgid ""
+"I<shm_perm.cuid> and I<shm_perm.uid> are set to the effective user ID of the "
+"calling process."
msgstr ""
#. type: Plain text
-#: build/C/man3/shm_open.3:200
+#: build/C/man2/shmget.2:161
msgid ""
-"Permission was denied to B<shm_open>() I<name> in the specified I<mode>, or "
-"B<O_TRUNC> was specified and the caller does not have write permission on "
-"the object."
-msgstr ""
-
-#. type: TP
-#: build/C/man3/shm_open.3:200 build/C/man2/shmget.2:192
-#, no-wrap
-msgid "B<EEXIST>"
+"I<shm_perm.cgid> and I<shm_perm.gid> are set to the effective group ID of "
+"the calling process."
msgstr ""
#. type: Plain text
-#: build/C/man3/shm_open.3:211
+#: build/C/man2/shmget.2:166
msgid ""
-"Both B<O_CREAT> and B<O_EXCL> were specified to B<shm_open>() and the "
-"shared memory object specified by I<name> already exists."
+"The least significant 9 bits of I<shm_perm.mode> are set to the least "
+"significant 9 bit of I<shmflg>."
msgstr ""
#. type: Plain text
-#: build/C/man3/shm_open.3:218
-msgid "The I<name> argument to B<shm_open>() was invalid."
-msgstr ""
-
-#. type: TP
-#: build/C/man3/shm_open.3:218
-#, no-wrap
-msgid "B<EMFILE>"
+#: build/C/man2/shmget.2:170
+msgid "I<shm_segsz> is set to the value of I<size>."
msgstr ""
#. type: Plain text
-#: build/C/man3/shm_open.3:221
-msgid "The process already has the maximum number of files open."
-msgstr ""
-
-#. type: TP
-#: build/C/man3/shm_open.3:221
-#, no-wrap
-msgid "B<ENAMETOOLONG>"
+#: build/C/man2/shmget.2:177
+msgid "I<shm_lpid>, I<shm_nattch>, I<shm_atime>, and I<shm_dtime> are set to 0."
msgstr ""
#. type: Plain text
-#: build/C/man3/shm_open.3:227
-msgid "The length of I<name> exceeds B<PATH_MAX>."
+#: build/C/man2/shmget.2:180
+msgid "I<shm_ctime> is set to the current time."
msgstr ""
#. type: Plain text
-#: build/C/man3/shm_open.3:231
-msgid "The limit on the total number of files open on the system has been reached."
-msgstr ""
-
-#. type: TP
-#: build/C/man3/shm_open.3:231 build/C/man3/shm_open.3:240 build/C/man2/shmget.2:206
-#, no-wrap
-msgid "B<ENOENT>"
+#: build/C/man2/shmget.2:183
+msgid ""
+"If the shared memory segment already exists, the permissions are verified, "
+"and a check is made to see if it is marked for destruction."
msgstr ""
#. type: Plain text
-#: build/C/man3/shm_open.3:240
+#: build/C/man2/shmget.2:188
msgid ""
-"An attempt was made to B<shm_open>() a I<name> that did not exist, and "
-"B<O_CREAT> was not specified."
+"On success, a valid shared memory identifier is returned. On error, -1 is "
+"returned, and I<errno> is set to indicate the error."
msgstr ""
#. type: Plain text
-#: build/C/man3/shm_open.3:247
-msgid "An attempt was to made to B<shm_unlink>() a I<name> that does not exist."
+#: build/C/man2/shmget.2:192
+msgid "On failure, I<errno> is set to one of the following:"
msgstr ""
#. type: Plain text
-#: build/C/man3/shm_open.3:249
-msgid "These functions are provided in glibc 2.2 and later."
+#: build/C/man2/shmget.2:198
+msgid ""
+"The user does not have permission to access the shared memory segment, and "
+"does not have the B<CAP_IPC_OWNER> capability."
msgstr ""
#. type: Plain text
-#: build/C/man3/shm_open.3:255
+#: build/C/man2/shmget.2:207
msgid ""
-"POSIX.1-2001 says that the group ownership of a newly created shared memory "
-"object is set to either the calling process's effective group ID or \"a "
-"system default group ID\"."
+"B<IPC_CREAT> and B<IPC_EXCL> were specified in I<shmflg>, but a shared "
+"memory segment already exists for I<key>."
msgstr ""
#. type: Plain text
-#: build/C/man3/shm_open.3:264
+#: build/C/man2/shmget.2:215
msgid ""
-"POSIX leaves the behavior of the combination of B<O_RDONLY> and B<O_TRUNC> "
-"unspecified. On Linux, this will successfully truncate an existing shared "
-"memory object\\(emthis may not be so on other UNIX systems."
+"A new segment was to be created and I<size> is less than B<SHMMIN> or "
+"greater than B<SHMMAX>."
msgstr ""
#. type: Plain text
-#: build/C/man3/shm_open.3:269
+#: build/C/man2/shmget.2:221
msgid ""
-"The POSIX shared memory object implementation on Linux 2.4 makes use of a "
-"dedicated file system, which is normally mounted under I</dev/shm>."
+"A segment for the given I<key> exists, but I<size> is greater than the size "
+"of that segment."
msgstr ""
#. type: Plain text
-#: build/C/man3/shm_open.3:279
-msgid ""
-"B<close>(2), B<fchmod>(2), B<fchown>(2), B<fcntl>(2), B<fstat>(2), "
-"B<ftruncate>(2), B<mmap>(2), B<open>(2), B<umask>(2), B<shm_overview>(7)"
+#: build/C/man2/shmget.2:230
+msgid "No segment exists for the given I<key>, and B<IPC_CREAT> was not specified."
msgstr ""
-#. type: TH
-#: build/C/man7/shm_overview.7:27
-#, no-wrap
-msgid "SHM_OVERVIEW"
+#. type: Plain text
+#: build/C/man2/shmget.2:233
+msgid "No memory could be allocated for segment overhead."
msgstr ""
#. type: Plain text
-#: build/C/man7/shm_overview.7:30
-msgid "shm_overview - Overview of POSIX shared memory"
+#: build/C/man2/shmget.2:241
+msgid ""
+"All possible shared memory IDs have been taken (B<SHMMNI>), or allocating a "
+"segment of the requested I<size> would cause the system to exceed the "
+"system-wide limit on shared memory (B<SHMALL>)."
msgstr ""
#. type: Plain text
-#: build/C/man7/shm_overview.7:33
+#: build/C/man2/shmget.2:248
msgid ""
-"The POSIX shared memory API allows processes to communicate information by "
-"sharing a region of memory."
+"The B<SHM_HUGETLB> flag was specified, but the caller was not privileged "
+"(did not have the B<CAP_IPC_LOCK> capability)."
msgstr ""
#. type: Plain text
-#: build/C/man7/shm_overview.7:35
-msgid "The interfaces employed in the API are:"
+#: build/C/man2/shmget.2:256
+msgid "B<SHM_HUGETLB> and B<SHM_NORESERVE> are Linux extensions."
msgstr ""
-#. type: TP
-#: build/C/man7/shm_overview.7:35
+#. type: Plain text
+#: build/C/man2/shmget.2:280
+msgid ""
+"B<IPC_PRIVATE> isn't a flag field but a I<key_t> type. If this special "
+"value is used for I<key>, the system call ignores all but the least "
+"significant 9 bits of I<shmflg> and creates a new shared memory segment."
+msgstr ""
+
+#. type: SS
+#: build/C/man2/shmget.2:280
#, no-wrap
-msgid "B<shm_open>(3)"
+msgid "Shared memory limits"
msgstr ""
#. type: Plain text
-#: build/C/man7/shm_overview.7:42
+#: build/C/man2/shmget.2:284
msgid ""
-"Create and open a new object, or open an existing object. This is analogous "
-"to B<open>(2). The call returns a file descriptor for use by the other "
-"interfaces listed below."
+"The following limits on shared memory segment resources affect the "
+"B<shmget>() call:"
msgstr ""
#. type: TP
-#: build/C/man7/shm_overview.7:42
+#: build/C/man2/shmget.2:284
#, no-wrap
-msgid "B<ftruncate>(2)"
+msgid "B<SHMALL>"
msgstr ""
#. type: Plain text
-#: build/C/man7/shm_overview.7:46
+#: build/C/man2/shmget.2:288
msgid ""
-"Set the size of the shared memory object. (A newly created shared memory "
-"object has a length of zero.)"
+"System-wide limit on the total amount of shared memory, measured in units of "
+"the system page size."
msgstr ""
+#. commit 060028bac94bf60a65415d1d55a359c3a17d5c31
#. type: Plain text
-#: build/C/man7/shm_overview.7:50
+#: build/C/man2/shmget.2:294
msgid ""
-"Map the shared memory object into the virtual address space of the calling "
-"process."
+"On Linux, this limit can be read and modified via "
+"I</proc/sys/kernel/shmall>. Since Linux 3.16, the default value for this "
+"limit is:"
msgstr ""
-#. type: TP
-#: build/C/man7/shm_overview.7:50
+#. type: Plain text
+#: build/C/man2/shmget.2:296 build/C/man2/shmget.2:331
#, no-wrap
-msgid "B<munmap>(2)"
+msgid " ULONG_MAX - 2^24\n"
msgstr ""
#. type: Plain text
-#: build/C/man7/shm_overview.7:54
+#: build/C/man2/shmget.2:307
msgid ""
-"Unmap the shared memory object from the virtual address space of the calling "
-"process."
-msgstr ""
-
-#. type: TP
-#: build/C/man7/shm_overview.7:54
-#, no-wrap
-msgid "B<shm_unlink>(3)"
+"The effect of this value (which is suitable for both 32-bit and 64-bit "
+"systems) is to impose no limitation on allocations. This value, rather "
+"than B<ULONG_MAX>, was chosen as the default to prevent some cases where "
+"historical applications simply raised the existing limit without first "
+"checking its current value. Such applications would cause the value to "
+"overflow if the limit was set at B<ULONG_MAX>."
msgstr ""
#. type: Plain text
-#: build/C/man7/shm_overview.7:57
-msgid "Remove a shared memory object name."
-msgstr ""
-
-#. type: TP
-#: build/C/man7/shm_overview.7:57
-#, no-wrap
-msgid "B<close>(2)"
+#: build/C/man2/shmget.2:310
+msgid "From Linux 2.4 up to Linux 3.15, the default value for this limit was:"
msgstr ""
#. type: Plain text
-#: build/C/man7/shm_overview.7:62
-msgid ""
-"Close the file descriptor allocated by B<shm_open>(3) when it is no longer "
-"needed."
-msgstr ""
-
-#. type: TP
-#: build/C/man7/shm_overview.7:62
+#: build/C/man2/shmget.2:312
#, no-wrap
-msgid "B<fstat>(2)"
+msgid " SHMMAX / PAGE_SIZE * (SHMMNI / 16)\n"
msgstr ""
#. type: Plain text
-#: build/C/man7/shm_overview.7:76
+#: build/C/man2/shmget.2:320
msgid ""
-"Obtain a I<stat> structure that describes the shared memory object. Among "
-"the information returned by this call are the object's size (I<st_size>), "
-"permissions (I<st_mode>), owner (I<st_uid>), and group (I<st_gid>)."
+"If B<SHMMAX> and B<SHMMNI> were not modified, then multiplying the result of "
+"this formula by the page size (to get a value in bytes) yielded a value of 8 "
+"GB as the limit on the total memory used by all shared memory segments."
msgstr ""
#. type: TP
-#: build/C/man7/shm_overview.7:76
+#: build/C/man2/shmget.2:320
#, no-wrap
-msgid "B<fchown>(2)"
+msgid "B<SHMMAX>"
msgstr ""
#. type: Plain text
-#: build/C/man7/shm_overview.7:79
-msgid "To change the ownership of a shared memory object."
+#: build/C/man2/shmget.2:323
+msgid "Maximum size in bytes for a shared memory segment."
msgstr ""
-#. type: TP
-#: build/C/man7/shm_overview.7:79
-#, no-wrap
-msgid "B<fchmod>(2)"
+#. commit 060028bac94bf60a65415d1d55a359c3a17d5c31
+#. type: Plain text
+#: build/C/man2/shmget.2:329
+msgid ""
+"On Linux, this limit can be read and modified via "
+"I</proc/sys/kernel/shmmax>. Since Linux 3.16, the default value for this "
+"limit is:"
msgstr ""
#. type: Plain text
-#: build/C/man7/shm_overview.7:82
-msgid "To change the permissions of a shared memory object."
+#: build/C/man2/shmget.2:340
+msgid ""
+"The effect of this value (which is suitable for both 32-bit and 64-bit "
+"systems) is to impose no limitation on allocations. See the description of "
+"B<SHMALL> for a discussion of why this default value (rather than "
+"B<ULONG_MAX>) is used."
msgstr ""
-#. type: SS
-#: build/C/man7/shm_overview.7:82
-#, no-wrap
-msgid "Versions"
+#. type: Plain text
+#: build/C/man2/shmget.2:343
+msgid ""
+"From Linux 2.2 up to Linux 3.15, the default value of this limit was "
+"0x2000000 (32MB)."
msgstr ""
#. type: Plain text
-#: build/C/man7/shm_overview.7:84
-msgid "POSIX shared memory is supported since Linux 2.4 and glibc 2.2."
+#: build/C/man2/shmget.2:349
+msgid ""
+"Because it is not possible to map just part of a shared memory segment, the "
+"amount of virtual memory places another limit on the maximum size of a "
+"usable segment: for example, on i386 the largest segments that can be mapped "
+"have a size of around 2.8 GB, and on x86_64 the limit is around 127 TB."
msgstr ""
-#. type: SS
-#: build/C/man7/shm_overview.7:84
+#. type: TP
+#: build/C/man2/shmget.2:349
#, no-wrap
-msgid "Persistence"
+msgid "B<SHMMIN>"
msgstr ""
#. type: Plain text
-#: build/C/man7/shm_overview.7:89
+#: build/C/man2/shmget.2:355
msgid ""
-"POSIX shared memory objects have kernel persistence: a shared memory object "
-"will exist until the system is shut down, or until all processes have "
-"unmapped the object and it has been deleted with B<shm_unlink>(3)"
+"Minimum size in bytes for a shared memory segment: implementation dependent "
+"(currently 1 byte, though B<PAGE_SIZE> is the effective minimum size)."
msgstr ""
-#. type: SS
-#: build/C/man7/shm_overview.7:89
+#. type: TP
+#: build/C/man2/shmget.2:355
#, no-wrap
-msgid "Linking"
+msgid "B<SHMMNI>"
msgstr ""
#. type: Plain text
-#: build/C/man7/shm_overview.7:94
+#: build/C/man2/shmget.2:360
msgid ""
-"Programs using the POSIX shared memory API must be compiled with I<cc -lrt> "
-"to link against the real-time library, I<librt>."
-msgstr ""
-
-#. type: SS
-#: build/C/man7/shm_overview.7:94
-#, no-wrap
-msgid "Accessing shared memory objects via the file system"
+"System-wide limit on the number of shared memory segments. In Linux 2.2, "
+"the default value for this limit was 128; since Linux 2.4, the default value "
+"is 4096."
msgstr ""
+#. Kernels between 2.4.x and 2.6.8 had an off-by-one error that meant
+#. that we could create one more segment than SHMMNI -- MTK
+#. This /proc file is not available in Linux 2.2 and earlier -- MTK
#. type: Plain text
-#: build/C/man7/shm_overview.7:101
+#: build/C/man2/shmget.2:366
msgid ""
-"On Linux, shared memory objects are created in a (I<tmpfs>) virtual file "
-"system, normally mounted under I</dev/shm>. Since kernel 2.6.19, Linux "
-"supports the use of access control lists (ACLs) to control the permissions "
-"of objects in the virtual file system."
+"On Linux, this limit can be read and modified via "
+"I</proc/sys/kernel/shmmni>."
msgstr ""
#. type: Plain text
-#: build/C/man7/shm_overview.7:106
+#: build/C/man2/shmget.2:370
msgid ""
-"Typically, processes must synchronize their access to a shared memory "
-"object, using, for example, POSIX semaphores."
+"The implementation has no specific limits for the per-process maximum number "
+"of shared memory segments (B<SHMSEG>)."
msgstr ""
#. type: Plain text
-#: build/C/man7/shm_overview.7:114
+#: build/C/man2/shmget.2:376
msgid ""
-"System V shared memory (B<shmget>(2), B<shmop>(2), etc.) is an older shared "
-"memory API. POSIX shared memory provides a simpler, and better designed "
-"interface; on the other hand POSIX shared memory is somewhat less widely "
-"available (especially on older systems) than System V shared memory."
+"Until version 2.3.30, Linux would return B<EIDRM> for a B<shmget>() on a "
+"shared memory segment scheduled for deletion."
msgstr ""
#. type: Plain text
-#: build/C/man7/shm_overview.7:126
+#: build/C/man2/shmget.2:382
msgid ""
-"B<fchmod>(2), B<fchown>(2), B<fstat>(2), B<ftruncate>(2), B<mmap>(2), "
-"B<mprotect>(2), B<munmap>(2), B<shmget>(2), B<shmop>(2), B<shm_open>(3), "
-"B<shm_unlink>(3), B<sem_overview>(7)"
+"The name choice B<IPC_PRIVATE> was perhaps unfortunate, B<IPC_NEW> would "
+"more clearly show its function."
msgstr ""
-#. type: TH
-#: build/C/man2/shmctl.2:43
-#, no-wrap
-msgid "SHMCTL"
+#. type: Plain text
+#: build/C/man2/shmget.2:391
+msgid ""
+"B<memfd_create>(2), B<shmat>(2), B<shmctl>(2), B<shmdt>(2), B<ftok>(3), "
+"B<capabilities>(7), B<shm_overview>(7), B<svipc>(7)"
msgstr ""
#. type: TH
-#: build/C/man2/shmctl.2:43
+#: build/C/man2/shmop.2:41
#, no-wrap
-msgid "2008-08-07"
+msgid "SHMOP"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:46
-msgid "shmctl - shared memory control"
+#: build/C/man2/shmop.2:44
+msgid "shmat, shmdt - System V shared memory operations"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:49 build/C/man2/shmget.2:42
-msgid "B<#include E<lt>sys/ipc.hE<gt>>"
+#: build/C/man2/shmop.2:48
+#, no-wrap
+msgid ""
+"B<#include E<lt>sys/types.hE<gt>>\n"
+"B<#include E<lt>sys/shm.hE<gt>>\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:51 build/C/man2/shmget.2:44
-msgid "B<#include E<lt>sys/shm.hE<gt>>"
+#: build/C/man2/shmop.2:50
+#, no-wrap
+msgid ""
+"B<void *shmat(int >I<shmid>B<, const void *>I<shmaddr>B<, int "
+">I<shmflg>B<);>\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:53
-msgid "B<int shmctl(int >I<shmid>B<, int >I<cmd>B<, struct shmid_ds *>I<buf>B<);>"
+#: build/C/man2/shmop.2:52
+#, no-wrap
+msgid "B<int shmdt(const void *>I<shmaddr>B<);>\n"
msgstr ""
-#. type: Plain text
-#: build/C/man2/shmctl.2:60
-msgid ""
-"B<shmctl>() performs the control operation specified by I<cmd> on the "
-"shared memory segment whose identifier is given in I<shmid>."
+#. type: SS
+#: build/C/man2/shmop.2:54
+#, no-wrap
+msgid "shmat()"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:65
+#: build/C/man2/shmop.2:62
msgid ""
-"The I<buf> argument is a pointer to a I<shmid_ds> structure, defined in "
-"I<E<lt>sys/shm.hE<gt>> as follows:"
+"B<shmat>() attaches the System\\ V shared memory segment identified by "
+"I<shmid> to the address space of the calling process. The attaching address "
+"is specified by I<shmaddr> with one of the following criteria:"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:79
-#, no-wrap
+#: build/C/man2/shmop.2:68
msgid ""
-"struct shmid_ds {\n"
-" struct ipc_perm shm_perm; /* Ownership and permissions */\n"
-" size_t shm_segsz; /* Size of segment (bytes) */\n"
-" time_t shm_atime; /* Last attach time */\n"
-" time_t shm_dtime; /* Last detach time */\n"
-" time_t shm_ctime; /* Last change time */\n"
-" pid_t shm_cpid; /* PID of creator */\n"
-" pid_t shm_lpid; /* PID of last shmat(2)/shmdt(2) */\n"
-" shmatt_t shm_nattch; /* No. of current attaches */\n"
-" ...\n"
-"};\n"
+"If I<shmaddr> is NULL, the system chooses a suitable (unused) address at "
+"which to attach the segment."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:87
+#: build/C/man2/shmop.2:80
msgid ""
-"The I<ipc_perm> structure is defined in I<E<lt>sys/ipc.hE<gt>> as follows "
-"(the highlighted fields are settable using B<IPC_SET>):"
+"If I<shmaddr> isn't NULL and B<SHM_RND> is specified in I<shmflg>, the "
+"attach occurs at the address equal to I<shmaddr> rounded down to the nearest "
+"multiple of B<SHMLBA>."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:100
-#, no-wrap
+#: build/C/man2/shmop.2:84
msgid ""
-"struct ipc_perm {\n"
-" key_t __key; /* Key supplied to shmget(2) */\n"
-" uid_t B<uid>; /* Effective UID of owner */\n"
-" gid_t B<gid>; /* Effective GID of owner */\n"
-" uid_t cuid; /* Effective UID of creator */\n"
-" gid_t cgid; /* Effective GID of creator */\n"
-" unsigned short B<mode>; /* B<Permissions> + SHM_DEST and\n"
-" SHM_LOCKED flags */\n"
-" unsigned short __seq; /* Sequence number */\n"
-"};\n"
+"Otherwise, I<shmaddr> must be a page-aligned address at which the attach "
+"occurs."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:106
-msgid "Valid values for I<cmd> are:"
+#: build/C/man2/shmop.2:90
+msgid ""
+"In addition to B<SHM_RND>, the following flags may be specified in the "
+"I<shmflg> bit-mask argument:"
msgstr ""
#. type: TP
-#: build/C/man2/shmctl.2:107
+#: build/C/man2/shmop.2:90
#, no-wrap
-msgid "B<IPC_STAT>"
+msgid "B<SHM_EXEC> (Linux-specific; since Linux 2.6.9)"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:116
+#: build/C/man2/shmop.2:94
msgid ""
-"Copy information from the kernel data structure associated with I<shmid> "
-"into the I<shmid_ds> structure pointed to by I<buf>. The caller must have "
-"read permission on the shared memory segment."
+"Allow the contents of the segment to be executed. The caller must have "
+"execute permission on the segment."
msgstr ""
#. type: TP
-#: build/C/man2/shmctl.2:116
+#: build/C/man2/shmop.2:94
#, no-wrap
-msgid "B<IPC_SET>"
+msgid "B<SHM_RDONLY>"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:134
+#: build/C/man2/shmop.2:102
msgid ""
-"Write the values of some members of the I<shmid_ds> structure pointed to by "
-"I<buf> to the kernel data structure associated with this shared memory "
-"segment, updating also its I<shm_ctime> member. The following fields can be "
-"changed: I<shm_perm.uid>, I<shm_perm.gid>, and (the least significant 9 bits "
-"of) I<shm_perm.mode>. The effective UID of the calling process must match "
-"the owner (I<shm_perm.uid>) or creator (I<shm_perm.cuid>) of the shared "
-"memory segment, or the caller must be privileged."
+"Attach the segment for read-only access. The process must have read "
+"permission for the segment. If this flag is not specified, the segment is "
+"attached for read and write access, and the process must have read and write "
+"permission for the segment. There is no notion of a write-only shared "
+"memory segment."
msgstr ""
#. type: TP
-#: build/C/man2/shmctl.2:134
+#: build/C/man2/shmop.2:102
#, no-wrap
-msgid "B<IPC_RMID>"
+msgid "B<SHM_REMAP> (Linux-specific)"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:151
+#: build/C/man2/shmop.2:115
msgid ""
-"Mark the segment to be destroyed. The segment will only actually be "
-"destroyed after the last process detaches it (i.e., when the I<shm_nattch> "
-"member of the associated structure I<shmid_ds> is zero). The caller must be "
-"the owner or creator, or be privileged. If a segment has been marked for "
-"destruction, then the (nonstandard) B<SHM_DEST> flag of the "
-"I<shm_perm.mode> field in the associated data structure retrieved by "
-"B<IPC_STAT> will be set."
+"This flag specifies that the mapping of the segment should replace any "
+"existing mapping in the range starting at I<shmaddr> and continuing for the "
+"size of the segment. (Normally, an B<EINVAL> error would result if a "
+"mapping already exists in this address range.) In this case, I<shmaddr> "
+"must not be NULL."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:154
+#: build/C/man2/shmop.2:122
msgid ""
-"The caller I<must> ensure that a segment is eventually destroyed; otherwise "
-"its pages that were faulted in will remain in memory or swap."
+"The B<brk>(2) value of the calling process is not altered by the attach. "
+"The segment will automatically be detached at process exit. The same "
+"segment may be attached as a read and as a read-write one, and more than "
+"once, in the process's address space."
msgstr ""
-#. type: TP
-#: build/C/man2/shmctl.2:154
-#, no-wrap
-msgid "B<IPC_INFO> (Linux-specific)"
+#. type: Plain text
+#: build/C/man2/shmop.2:130
+msgid ""
+"A successful B<shmat>() call updates the members of the I<shmid_ds> "
+"structure (see B<shmctl>(2)) associated with the shared memory segment as "
+"follows:"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:167
-msgid ""
-"Returns information about system-wide shared memory limits and parameters in "
-"the structure pointed to by I<buf>. This structure is of type I<shminfo> "
-"(thus, a cast is required), defined in I<E<lt>sys/shm.hE<gt>> if the "
-"B<_GNU_SOURCE> feature test macro is defined:"
+#: build/C/man2/shmop.2:133
+msgid "I<shm_atime> is set to the current time."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:181
+#: build/C/man2/shmop.2:136 build/C/man2/shmop.2:163
+msgid "I<shm_lpid> is set to the process-ID of the calling process."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/shmop.2:140
+msgid "I<shm_nattch> is incremented by one."
+msgstr ""
+
+#. type: SS
+#: build/C/man2/shmop.2:140
#, no-wrap
+msgid "shmdt()"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/shmop.2:151
msgid ""
-"struct shminfo {\n"
-" unsigned long shmmax; /* Maximum segment size */\n"
-" unsigned long shmmin; /* Minimum segment size;\n"
-" always 1 */\n"
-" unsigned long shmmni; /* Maximum number of segments */\n"
-" unsigned long shmseg; /* Maximum number of segments\n"
-" that a process can attach;\n"
-" unused within kernel */\n"
-" unsigned long shmall; /* Maximum number of pages of\n"
-" shared memory, system-wide */\n"
-"};\n"
+"B<shmdt>() detaches the shared memory segment located at the address "
+"specified by I<shmaddr> from the address space of the calling process. The "
+"to-be-detached segment must be currently attached with I<shmaddr> equal to "
+"the value returned by the attaching B<shmat>() call."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:194
+#: build/C/man2/shmop.2:157
msgid ""
-"The I<shmmni>, I<shmmax>, and I<shmall> settings can be changed via I</proc> "
-"files of the same name; see B<proc>(5) for details."
+"On a successful B<shmdt>() call, the system updates the members of the "
+"I<shmid_ds> structure associated with the shared memory segment as follows:"
msgstr ""
-#. type: TP
-#: build/C/man2/shmctl.2:194
-#, no-wrap
-msgid "B<SHM_INFO> (Linux-specific)"
+#. type: Plain text
+#: build/C/man2/shmop.2:160
+msgid "I<shm_dtime> is set to the current time."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:205
+#: build/C/man2/shmop.2:168
msgid ""
-"Returns a I<shm_info> structure whose fields contain information about "
-"system resources consumed by shared memory. This structure is defined in "
-"I<E<lt>sys/shm.hE<gt>> if the B<_GNU_SOURCE> feature test macro is defined:"
+"I<shm_nattch> is decremented by one. If it becomes 0 and the segment is "
+"marked for deletion, the segment is deleted."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:222
-#, no-wrap
+#: build/C/man2/shmop.2:176
msgid ""
-"struct shm_info {\n"
-" int used_ids; /* # of currently existing\n"
-" segments */\n"
-" unsigned long shm_tot; /* Total number of shared\n"
-" memory pages */\n"
-" unsigned long shm_rss; /* # of resident shared\n"
-" memory pages */\n"
-" unsigned long shm_swp; /* # of swapped shared\n"
-" memory pages */\n"
-" unsigned long swap_attempts;\n"
-" /* Unused since Linux 2.4 */\n"
-" unsigned long swap_successes;\n"
-" /* Unused since Linux 2.4 */\n"
-"};\n"
+"On success, B<shmat>() returns the address of the attached shared memory "
+"segment; on error, I<(void\\ *)\\ -1> is returned, and I<errno> is set to "
+"indicate the cause of the error."
msgstr ""
-#. type: TP
-#: build/C/man2/shmctl.2:224
-#, no-wrap
-msgid "B<SHM_STAT> (Linux-specific)"
+#. type: Plain text
+#: build/C/man2/shmop.2:182
+msgid ""
+"On success, B<shmdt>() returns 0; on error -1 is returned, and I<errno> is "
+"set to indicate the cause of the error."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:235
+#: build/C/man2/shmop.2:188
+msgid "When B<shmat>() fails, I<errno> is set to one of the following:"
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/shmop.2:194
msgid ""
-"Returns a I<shmid_ds> structure as for B<IPC_STAT>. However, the I<shmid> "
-"argument is not a segment identifier, but instead an index into the kernel's "
-"internal array that maintains information about all shared memory segments "
-"on the system."
+"The calling process does not have the required permissions for the requested "
+"attach type, and does not have the B<CAP_IPC_OWNER> capability."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:238
+#: build/C/man2/shmop.2:211
msgid ""
-"The caller can prevent or allow swapping of a shared memory segment with the "
-"following I<cmd> values:"
+"Invalid I<shmid> value, unaligned (i.e., not page-aligned and B<SHM_RND> was "
+"not specified) or invalid I<shmaddr> value, or can't attach segment at "
+"I<shmaddr>, or B<SHM_REMAP> was specified and I<shmaddr> was NULL."
msgstr ""
-#. type: TP
-#: build/C/man2/shmctl.2:239
-#, no-wrap
-msgid "B<SHM_LOCK> (Linux-specific)"
+#. type: Plain text
+#: build/C/man2/shmop.2:214
+msgid "Could not allocate memory for the descriptor or for the page tables."
+msgstr ""
+
+#. type: Plain text
+#: build/C/man2/shmop.2:220
+msgid "When B<shmdt>() fails, I<errno> is set as follows:"
msgstr ""
+#. The following since 2.6.17-rc1:
#. type: Plain text
-#: build/C/man2/shmctl.2:251
+#: build/C/man2/shmop.2:228
msgid ""
-"Prevent swapping of the shared memory segment. The caller must fault in any "
-"pages that are required to be present after locking is enabled. If a "
-"segment has been locked, then the (nonstandard) B<SHM_LOCKED> flag of the "
-"I<shm_perm.mode> field in the associated data structure retrieved by "
-"B<IPC_STAT> will be set."
+"There is no shared memory segment attached at I<shmaddr>; or, I<shmaddr> is "
+"not aligned on a page boundary."
msgstr ""
-#. type: TP
-#: build/C/man2/shmctl.2:251
-#, no-wrap
-msgid "B<SHM_UNLOCK> (Linux-specific)"
+#. type: Plain text
+#: build/C/man2/shmop.2:243
+msgid ""
+"In SVID 3 (or perhaps earlier), the type of the I<shmaddr> argument was "
+"changed from I<char\\ *> into I<const void\\ *>, and the returned type of "
+"B<shmat>() from I<char\\ *> into I<void\\ *>."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:254
-msgid "Unlock the segment, allowing it to be swapped out."
+#: build/C/man2/shmop.2:248
+msgid "After a B<fork>(2), the child inherits the attached shared memory segments."
msgstr ""
-#. There was some weirdness in 2.6.9: SHM_LOCK and SHM_UNLOCK could
-#. be applied to a segment, regardless of ownership of the segment.
-#. This was a botch-up in the move to RLIMIT_MEMLOCK, and was fixed
-#. in 2.6.10. MTK, May 2005
#. type: Plain text
-#: build/C/man2/shmctl.2:272
+#: build/C/man2/shmop.2:252
msgid ""
-"In kernels before 2.6.10, only a privileged process could employ B<SHM_LOCK> "
-"and B<SHM_UNLOCK>. Since kernel 2.6.10, an unprivileged process can employ "
-"these operations if its effective UID matches the owner or creator UID of "
-"the segment, and (for B<SHM_LOCK>) the amount of memory to be locked falls "
-"within the B<RLIMIT_MEMLOCK> resource limit (see B<setrlimit>(2))."
+"After an B<execve>(2), all attached shared memory segments are detached from "
+"the process."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:290
+#: build/C/man2/shmop.2:256
msgid ""
-"A successful B<IPC_INFO> or B<SHM_INFO> operation returns the index of the "
-"highest used entry in the kernel's internal array recording information "
-"about all shared memory segments. (This information can be used with "
-"repeated B<SHM_STAT> operations to obtain information about all shared "
-"memory segments on the system.) A successful B<SHM_STAT> operation returns "
-"the identifier of the shared memory segment whose index was given in "
-"I<shmid>. Other operations return 0 on success."
+"Upon B<_exit>(2), all attached shared memory segments are detached from the "
+"process."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:294
-msgid "On error, -1 is returned, and I<errno> is set appropriately."
+#: build/C/man2/shmop.2:268
+msgid ""
+"Using B<shmat>() with I<shmaddr> equal to NULL is the preferred, portable "
+"way of attaching a shared memory segment. Be aware that the shared memory "
+"segment attached in this way may be attached at different addresses in "
+"different processes. Therefore, any pointers maintained within the shared "
+"memory must be made relative (typically to the starting address of the "
+"segment), rather than absolute."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:303
+#: build/C/man2/shmop.2:273
msgid ""
-"B<IPC_STAT> or B<SHM_STAT> is requested and I<shm_perm.mode> does not allow "
-"read access for I<shmid>, and the calling process does not have the "
-"B<CAP_IPC_OWNER> capability."
+"On Linux, it is possible to attach a shared memory segment even if it is "
+"already marked to be deleted. However, POSIX.1-2001 does not specify this "
+"behavior and many other implementations do not support it."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:314
-msgid ""
-"The argument I<cmd> has value B<IPC_SET> or B<IPC_STAT> but the address "
-"pointed to by I<buf> isn't accessible."
+#: build/C/man2/shmop.2:276
+msgid "The following system parameter affects B<shmat>():"
msgstr ""
#. type: TP
-#: build/C/man2/shmctl.2:314
+#: build/C/man2/shmop.2:276
#, no-wrap
-msgid "B<EIDRM>"
+msgid "B<SHMLBA>"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:317
-msgid "I<shmid> points to a removed identifier."
+#: build/C/man2/shmop.2:289
+msgid ""
+"Segment low boundary address multiple. When explicitly specifying an attach "
+"address in a call to B<shmat>(), the caller should ensure that the address "
+"is a multiple of this value. This is necessary on some architectures, in "
+"order either to ensure good CPU cache performance or to ensure that "
+"different attaches of the same segment have consistent views within the CPU "
+"cache. B<SHMLBA> is normally some multiple of the system page size (on many "
+"Linux architectures, it is the same as the system page size)."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:326
+#: build/C/man2/shmop.2:293
msgid ""
-"I<shmid> is not a valid identifier, or I<cmd> is not a valid command. Or: "
-"for a B<SHM_STAT> operation, the index value specified in I<shmid> referred "
-"to an array slot that is currently unused."
+"The implementation places no intrinsic per-process limit on the number of "
+"shared memory segments (B<SHMSEG>)."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:337
+#: build/C/man2/shmop.2:301
msgid ""
-"(In kernels since 2.6.9), B<SHM_LOCK> was specified and the size of the "
-"to-be-locked segment would mean that the total bytes in locked shared memory "
-"segments would exceed the limit for the real user ID of the calling "
-"process. This limit is defined by the B<RLIMIT_MEMLOCK> soft resource limit "
-"(see B<setrlimit>(2))."
+"B<brk>(2), B<mmap>(2), B<shmctl>(2), B<shmget>(2), B<capabilities>(7), "
+"B<shm_overview>(7), B<svipc>(7)"
msgstr ""
-#. type: TP
-#: build/C/man2/shmctl.2:337
+#. type: TH
+#: build/C/man2/subpage_prot.2:30
#, no-wrap
-msgid "B<EOVERFLOW>"
+msgid "SUBPAGE_PROT"
msgstr ""
-#. type: Plain text
-#: build/C/man2/shmctl.2:342
-msgid ""
-"B<IPC_STAT> is attempted, and the GID or UID value is too large to be stored "
-"in the structure pointed to by I<buf>."
+#. type: TH
+#: build/C/man2/subpage_prot.2:30
+#, no-wrap
+msgid "2012-07-13"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:354
-msgid ""
-"B<IPC_SET> or B<IPC_RMID> is attempted, and the effective user ID of the "
-"calling process is not that of the creator (found in I<shm_perm.cuid>), or "
-"the owner (found in I<shm_perm.uid>), and the process was not privileged "
-"(Linux: did not have the B<CAP_SYS_ADMIN> capability)."
+#: build/C/man2/subpage_prot.2:33
+msgid "subpage_prot - define a subpage protection for an address range"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:366
+#: build/C/man2/subpage_prot.2:37
+#, no-wrap
msgid ""
-"Or (in kernels before 2.6.9), B<SHM_LOCK> or B<SHM_UNLOCK> was specified, "
-"but the process was not privileged (Linux: did not have the B<CAP_IPC_LOCK> "
-"capability). (Since Linux 2.6.9, this error can also occur if the "
-"B<RLIMIT_MEMLOCK> is 0 and the caller is not privileged.)"
+"B<long subpage_prot(unsigned long >I<addr>B<, unsigned long >I<len>B<,>\n"
+"B< uint32_t *>I<map>B<);>\n"
msgstr ""
-#. SVr4 documents an additional error condition EMFILE.
#. type: Plain text
-#: build/C/man2/shmctl.2:371 build/C/man2/shmget.2:232 build/C/man2/shmop.2:229
-msgid "SVr4, POSIX.1-2001."
+#: build/C/man2/subpage_prot.2:41
+msgid "I<Note>: There is no glibc wrapper for this system call; see NOTES."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:382
+#: build/C/man2/subpage_prot.2:47
msgid ""
-"The B<IPC_INFO>, B<SHM_STAT> and B<SHM_INFO> operations are used by the "
-"B<ipcs>(1) program to provide information on allocated resources. In the "
-"future these may modified or moved to a /proc file system interface."
+"The PowerPC-specific B<subpage_prot>() system call provides the facility to "
+"control the access permissions on individual 4kB subpages on systems "
+"configured with a page size of 64kB."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:390
+#: build/C/man2/subpage_prot.2:54
msgid ""
-"Linux permits a process to attach (B<shmat>(2)) a shared memory segment "
-"that has already been marked for deletion using I<shmctl(IPC_RMID)>. This "
-"feature is not available on other UNIX implementations; portable "
-"applications should avoid relying on it."
+"The protection map is applied to the memory pages in the region starting at "
+"I<addr> and continuing for I<len> bytes. Both of these arguments must be "
+"aligned to a 64-kB boundary."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:403
+#: build/C/man2/subpage_prot.2:66
msgid ""
-"Various fields in a I<struct shmid_ds> were typed as I<short> under Linux "
-"2.2 and have become I<long> under Linux 2.4. To take advantage of this, a "
-"recompilation under glibc-2.1.91 or later should suffice. (The kernel "
-"distinguishes old and new calls by an B<IPC_64> flag in I<cmd>.)"
+"The protection map is specified in the buffer pointed to by I<map>. The map "
+"has 2 bits per 4kB subpage; thus each 32-bit word specifies the protections "
+"of 16 4kB subpages inside a 64kB page (so, the number of 32-bit words "
+"pointed to by I<map> should equate to the number of 64-kB pages specified by "
+"I<len>). Each 2-bit field in the protection map is either 0 to allow any "
+"access, 1 to prevent writes, or 2 or 3 to prevent all accesses."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmctl.2:409
+#: build/C/man2/subpage_prot.2:71
msgid ""
-"B<mlock>(2), B<setrlimit>(2), B<shmget>(2), B<shmop>(2), B<capabilities>(7), "
-"B<svipc>(7)"
-msgstr ""
-
-#. type: TH
-#: build/C/man2/shmget.2:36
-#, no-wrap
-msgid "SHMGET"
+"On success, B<subpage_prot>() returns 0. Otherwise, one of the error codes "
+"specified below is returned."
msgstr ""
-#. type: TH
-#: build/C/man2/shmget.2:36
-#, no-wrap
-msgid "2006-05-02"
+#. type: Plain text
+#: build/C/man2/subpage_prot.2:77
+msgid "The buffer referred to by I<map> is not accessible."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:39
-msgid "shmget - allocates a shared memory segment"
+#: build/C/man2/subpage_prot.2:87
+msgid ""
+"The I<addr> or I<len> arguments are incorrect. Both of these arguments must "
+"be aligned to a multiple of the system page size, and they must not refer to "
+"a region outside of the address space of the process or to a region that "
+"consists of huge pages."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:46
-msgid "B<int shmget(key_t >I<key>B<, size_t >I<size>B<, int >I<shmflg>B<);>"
+#: build/C/man2/subpage_prot.2:90 build/C/man2/sync_file_range.2:166
+msgid "Out of memory."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:70
+#: build/C/man2/subpage_prot.2:96
msgid ""
-"B<shmget>() returns the identifier of the shared memory segment associated "
-"with the value of the argument I<key>. A new shared memory segment, with "
-"size equal to the value of I<size> rounded up to a multiple of B<PAGE_SIZE>, "
-"is created if I<key> has the value B<IPC_PRIVATE> or I<key> isn't "
-"B<IPC_PRIVATE>, no shared memory segment corresponding to I<key> exists, and "
-"B<IPC_CREAT> is specified in I<shmflg>."
+"This system call is provided on the PowerPC architecture since Linux "
+"2.6.25. The system call is provided only if the kernel is configured with "
+"B<CONFIG_PPC_64K_PAGES>. No library support is provided."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:89
+#: build/C/man2/subpage_prot.2:101
msgid ""
-"If I<shmflg> specifies both B<IPC_CREAT> and B<IPC_EXCL> and a shared memory "
-"segment already exists for I<key>, then B<shmget>() fails with I<errno> set "
-"to B<EEXIST>. (This is analogous to the effect of the combination B<O_CREAT "
-"| O_EXCL> for B<open>(2).)"
+"Glibc does not provide a wrapper for this system call; call it using "
+"B<syscall>(2)."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:93
-msgid "The value I<shmflg> is composed of:"
+#: build/C/man2/subpage_prot.2:106
+msgid ""
+"Normal page protections (at the 64-kB page level) also apply; the subpage "
+"protection mechanism is an additional constraint, so putting 0 in a 2-bit "
+"field won't allow writes to a page that is otherwise write-protected."
msgstr ""
-#. type: TP
-#: build/C/man2/shmget.2:93
+#. type: SS
+#: build/C/man2/subpage_prot.2:106
#, no-wrap
-msgid "B<IPC_CREAT>"
+msgid "Rationale"
msgstr ""
+#. In the initial implementation, it was the case that:
+#. In fact the whole process is switched to use 4k hardware pages when the
+#. subpage_prot system call is used, but this could be improved in future
+#. to switch only the affected segments.
+#. But Paul Mackerass says (Oct 2010): I'm pretty sure we now only switch
+#. the affected segment, not the whole process.
#. type: Plain text
-#: build/C/man2/shmget.2:100
+#: build/C/man2/subpage_prot.2:128
msgid ""
-"to create a new segment. If this flag is not used, then B<shmget>() will "
-"find the segment associated with I<key> and check to see if the user has "
-"permission to access the segment."
+"This system call is provided to assist writing emulators that operate using "
+"64-kB pages on PowerPC systems. When emulating systems such as x86, which "
+"uses a smaller page size, the emulator can no longer use the "
+"memory-management unit (MMU) and normal system calls for controlling page "
+"protections. (The emulator could emulate the MMU by checking and possibly "
+"remapping the address for each memory access in software, but that is slow.) "
+"The idea is that the emulator supplies an array of protection masks to apply "
+"to a specified range of virtual addresses. These masks are applied at the "
+"level where hardware page-table entries (PTEs) are inserted into the "
+"hardware page table based on the Linux PTEs, so the Linux PTEs are not "
+"affected. Implicit in this is that the regions of the address space that "
+"are protected are switched to use 4-kB hardware pages rather than 64-kB "
+"hardware pages (on machines with hardware 64-kB page support)."
msgstr ""
-#. type: TP
-#: build/C/man2/shmget.2:100
-#, no-wrap
-msgid "B<IPC_EXCL>"
+#. type: Plain text
+#: build/C/man2/subpage_prot.2:131
+msgid "B<mprotect>(2), B<syscall>(2)"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:103
-msgid "used with B<IPC_CREAT> to ensure failure if the segment already exists."
+#: build/C/man2/subpage_prot.2:134
+msgid "I<Documentation/vm/hugetlbpage.txt> in the Linux kernel source tree"
msgstr ""
-#. type: TP
-#: build/C/man2/shmget.2:103
+#. type: TH
+#: build/C/man2/sync_file_range.2:30
#, no-wrap
-msgid "I<mode_flags>"
+msgid "SYNC_FILE_RANGE"
msgstr ""
-#. type: Plain text
-#: build/C/man2/shmget.2:113
-msgid ""
-"(least significant 9 bits) specifying the permissions granted to the owner, "
-"group, and world. These bits have the same format, and the same meaning, as "
-"the I<mode> argument of B<open>(2). Presently, the execute permissions are "
-"not used by the system."
+#. type: TH
+#: build/C/man2/sync_file_range.2:30
+#, no-wrap
+msgid "2014-08-19"
msgstr ""
-#. type: TP
-#: build/C/man2/shmget.2:113
-#, no-wrap
-msgid "B<SHM_HUGETLB> (since Linux 2.6)"
+#. type: Plain text
+#: build/C/man2/sync_file_range.2:33
+msgid "sync_file_range - sync a file segment with disk"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:119
+#: build/C/man2/sync_file_range.2:37
+#, no-wrap
msgid ""
-"Allocate the segment using \"huge pages.\" See the kernel source file "
-"I<Documentation/vm/hugetlbpage.txt> for further information."
+"B<#define _GNU_SOURCE> /* See feature_test_macros(7) */\n"
+"B<#include E<lt>fcntl.hE<gt>>\n"
msgstr ""
-#. type: TP
-#: build/C/man2/shmget.2:119
+#. type: Plain text
+#: build/C/man2/sync_file_range.2:40
#, no-wrap
-msgid "B<SHM_NORESERVE> (since Linux 2.6.15)"
+msgid ""
+"B<int sync_file_range(int >I<fd>B<, off64_t >I<offset>B<, off64_t "
+">I<nbytes>B<,>\n"
+"B< unsigned int >I<flags>B<);>\n"
msgstr ""
-#. As at 2.6.17-rc2, this flag has no effect if SHM_HUGETLB was also
-#. specified.
#. type: Plain text
-#: build/C/man2/shmget.2:138
+#: build/C/man2/sync_file_range.2:47
msgid ""
-"This flag serves the same purpose as the B<mmap>(2) B<MAP_NORESERVE> flag. "
-"Do not reserve swap space for this segment. When swap space is reserved, "
-"one has the guarantee that it is possible to modify the segment. When swap "
-"space is not reserved one might get B<SIGSEGV> upon a write if no physical "
-"memory is available. See also the discussion of the file "
-"I</proc/sys/vm/overcommit_memory> in B<proc>(5)."
+"B<sync_file_range>() permits fine control when synchronizing the open file "
+"referred to by the file descriptor I<fd> with disk."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:146
+#: build/C/man2/sync_file_range.2:61
msgid ""
-"When a new shared memory segment is created, its contents are initialized to "
-"zero values, and its associated data structure, I<shmid_ds> (see "
-"B<shmctl>(2)), is initialized as follows:"
+"I<offset> is the starting byte of the file range to be synchronized. "
+"I<nbytes> specifies the length of the range to be synchronized, in bytes; if "
+"I<nbytes> is zero, then all bytes from I<offset> through to the end of file "
+"are synchronized. Synchronization is in units of the system page size: "
+"I<offset> is rounded down to a page boundary; I<(offset+nbytes-1)> is "
+"rounded up to a page boundary."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:151
-msgid ""
-"I<shm_perm.cuid> and I<shm_perm.uid> are set to the effective user ID of the "
-"calling process."
+#: build/C/man2/sync_file_range.2:65
+msgid "The I<flags> bit-mask argument can include any of the following values:"
+msgstr ""
+
+#. type: TP
+#: build/C/man2/sync_file_range.2:65
+#, no-wrap
+msgid "B<SYNC_FILE_RANGE_WAIT_BEFORE>"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:156
+#: build/C/man2/sync_file_range.2:70
msgid ""
-"I<shm_perm.cgid> and I<shm_perm.gid> are set to the effective group ID of "
-"the calling process."
+"Wait upon write-out of all pages in the specified range that have already "
+"been submitted to the device driver for write-out before performing any "
+"write."
+msgstr ""
+
+#. type: TP
+#: build/C/man2/sync_file_range.2:70 build/C/man2/sync_file_range.2:120
+#, no-wrap
+msgid "B<SYNC_FILE_RANGE_WRITE>"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:161
+#: build/C/man2/sync_file_range.2:76
msgid ""
-"The least significant 9 bits of I<shm_perm.mode> are set to the least "
-"significant 9 bit of I<shmflg>."
+"Initiate write-out of all dirty pages in the specified range which are not "
+"presently submitted write-out. Note that even this may block if you attempt "
+"to write more than request queue size."
msgstr ""
-#. type: Plain text
-#: build/C/man2/shmget.2:165
-msgid "I<shm_segsz> is set to the value of I<size>."
+#. type: TP
+#: build/C/man2/sync_file_range.2:76
+#, no-wrap
+msgid "B<SYNC_FILE_RANGE_WAIT_AFTER>"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:172
-msgid "I<shm_lpid>, I<shm_nattch>, I<shm_atime> and I<shm_dtime> are set to 0."
+#: build/C/man2/sync_file_range.2:80
+msgid "Wait upon write-out of all pages in the range after performing any write."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:175
-msgid "I<shm_ctime> is set to the current time."
+#: build/C/man2/sync_file_range.2:84
+msgid "Specifying I<flags> as 0 is permitted, as a no-op."
+msgstr ""
+
+#. type: SS
+#: build/C/man2/sync_file_range.2:84
+#, no-wrap
+msgid "Warning"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:178
+#: build/C/man2/sync_file_range.2:100
msgid ""
-"If the shared memory segment already exists, the permissions are verified, "
-"and a check is made to see if it is marked for destruction."
+"This system call is extremely dangerous and should not be used in portable "
+"programs. None of these operations writes out the file's metadata. "
+"Therefore, unless the application is strictly performing overwrites of "
+"already-instantiated disk blocks, there are no guarantees that the data will "
+"be available after a crash. There is no user interface to know if a write "
+"is purely an overwrite. On filesystems using copy-on-write semantics (e.g., "
+"I<btrfs>) an overwrite of existing allocated blocks is impossible. When "
+"writing into preallocated space, many filesystems also require calls into "
+"the block allocator, which this system call does not sync out to disk. This "
+"system call does not flush disk write caches and thus does not provide any "
+"data integrity on systems with volatile disk write caches."
msgstr ""
-#. type: Plain text
-#: build/C/man2/shmget.2:182
-msgid "A valid segment identifier, I<shmid>, is returned on success, -1 on error."
+#. type: SS
+#: build/C/man2/sync_file_range.2:100
+#, no-wrap
+msgid "Some details"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:186
-msgid "On failure, I<errno> is set to one of the following:"
+#: build/C/man2/sync_file_range.2:108
+msgid ""
+"B<SYNC_FILE_RANGE_WAIT_BEFORE> and B<SYNC_FILE_RANGE_WAIT_AFTER> will detect "
+"any I/O errors or B<ENOSPC> conditions and will return these to the caller."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:192
-msgid ""
-"The user does not have permission to access the shared memory segment, and "
-"does not have the B<CAP_IPC_OWNER> capability."
+#: build/C/man2/sync_file_range.2:112
+msgid "Useful combinations of the I<flags> bits are:"
msgstr ""
-#. type: Plain text
-#: build/C/man2/shmget.2:196
-msgid "B<IPC_CREAT | IPC_EXCL> was specified and the segment exists."
+#. type: TP
+#: build/C/man2/sync_file_range.2:112
+#, no-wrap
+msgid "B<SYNC_FILE_RANGE_WAIT_BEFORE | SYNC_FILE_RANGE_WRITE>"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:202
+#: build/C/man2/sync_file_range.2:120
msgid ""
-"A new segment was to be created and I<size> E<lt> B<SHMMIN> or I<size> E<gt> "
-"B<SHMMAX>, or no new segment was to be created, a segment with given key "
-"existed, but I<size> is greater than the size of that segment."
+"Ensures that all pages in the specified range which were dirty when "
+"B<sync_file_range>() was called are placed under write-out. This is a "
+"start-write-for-data-integrity operation."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:211
-msgid "No segment exists for the given I<key>, and B<IPC_CREAT> was not specified."
+#: build/C/man2/sync_file_range.2:127
+msgid ""
+"Start write-out of all dirty pages in the specified range which are not "
+"presently under write-out. This is an asynchronous flush-to-disk "
+"operation. This is not suitable for data integrity operations."
msgstr ""
-#. type: Plain text
-#: build/C/man2/shmget.2:214
-msgid "No memory could be allocated for segment overhead."
+#. type: TP
+#: build/C/man2/sync_file_range.2:127
+#, no-wrap
+msgid "B<SYNC_FILE_RANGE_WAIT_BEFORE> (or B<SYNC_FILE_RANGE_WAIT_AFTER>)"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:222
+#: build/C/man2/sync_file_range.2:134
msgid ""
-"All possible shared memory IDs have been taken (B<SHMMNI>), or allocating a "
-"segment of the requested I<size> would cause the system to exceed the "
-"system-wide limit on shared memory (B<SHMALL>)."
+"Wait for completion of write-out of all pages in the specified range. This "
+"can be used after an earlier B<SYNC_FILE_RANGE_WAIT_BEFORE | "
+"SYNC_FILE_RANGE_WRITE> operation to wait for completion of that operation, "
+"and obtain its result."
msgstr ""
-#. type: Plain text
-#: build/C/man2/shmget.2:229
+#. type: TP
+#: build/C/man2/sync_file_range.2:134
+#, no-wrap
msgid ""
-"The B<SHM_HUGETLB> flag was specified, but the caller was not privileged "
-"(did not have the B<CAP_IPC_LOCK> capability)."
+"B<SYNC_FILE_RANGE_WAIT_BEFORE | SYNC_FILE_RANGE_WRITE | "
+"SYNC_FILE_RANGE_WAIT_AFTER>"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:235
-msgid "B<SHM_HUGETLB> is a nonportable Linux extension."
+#: build/C/man2/sync_file_range.2:141
+msgid ""
+"This is a write-for-data-integrity operation that will ensure that all pages "
+"in the specified range which were dirty when B<sync_file_range>() was "
+"called are committed to disk."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:245
+#: build/C/man2/sync_file_range.2:147
msgid ""
-"B<IPC_PRIVATE> isn't a flag field but a I<key_t> type. If this special "
-"value is used for I<key>, the system call ignores everything but the least "
-"significant 9 bits of I<shmflg> and creates a new shared memory segment (on "
-"success)."
+"On success, B<sync_file_range>() returns 0; on failure -1 is returned and "
+"I<errno> is set to indicate the error."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:249
-msgid ""
-"The following limits on shared memory segment resources affect the "
-"B<shmget>() call:"
+#: build/C/man2/sync_file_range.2:152
+msgid "I<fd> is not a valid file descriptor."
msgstr ""
-#. type: TP
-#: build/C/man2/shmget.2:249
-#, no-wrap
-msgid "B<SHMALL>"
+#. type: Plain text
+#: build/C/man2/sync_file_range.2:160
+msgid "I<flags> specifies an invalid bit; or I<offset> or I<nbytes> is invalid."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:254
-msgid ""
-"System wide maximum of shared memory pages (on Linux, this limit can be read "
-"and modified via I</proc/sys/kernel/shmall>)."
+#: build/C/man2/sync_file_range.2:163
+msgid "I/O error."
msgstr ""
-#. type: TP
-#: build/C/man2/shmget.2:254
-#, no-wrap
-msgid "B<SHMMAX>"
+#. type: Plain text
+#: build/C/man2/sync_file_range.2:169
+msgid "Out of disk space."
msgstr ""
+#. FIXME . (bug?) Actually, how can 'fd' refer to a symbolic link (S_ISLNK)?
+#. (In user space at least) it isn't possible to obtain a file descriptor
+#. for a symbolic link.
#. type: Plain text
-#: build/C/man2/shmget.2:259
+#: build/C/man2/sync_file_range.2:177
msgid ""
-"Maximum size in bytes for a shared memory segment: policy dependent (on "
-"Linux, this limit can be read and modified via I</proc/sys/kernel/shmmax>)."
+"I<fd> refers to something other than a regular file, a block device, a "
+"directory, or a symbolic link."
msgstr ""
-#. type: TP
-#: build/C/man2/shmget.2:259
-#, no-wrap
-msgid "B<SHMMIN>"
+#. type: Plain text
+#: build/C/man2/sync_file_range.2:180
+msgid "B<sync_file_range>() appeared on Linux in kernel 2.6.17."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:265
+#: build/C/man2/sync_file_range.2:183
msgid ""
-"Minimum size in bytes for a shared memory segment: implementation dependent "
-"(currently 1 byte, though B<PAGE_SIZE> is the effective minimum size)."
+"This system call is Linux-specific, and should be avoided in portable "
+"programs."
msgstr ""
-#. type: TP
-#: build/C/man2/shmget.2:265
+#. type: SS
+#: build/C/man2/sync_file_range.2:184
#, no-wrap
-msgid "B<SHMMNI>"
+msgid "sync_file_range2()"
msgstr ""
-#. Kernels between 2.4.x and 2.6.8 had an off-by-one error that meant
-#. that we could create one more segment than SHMMNI -- MTK
-#. This /proc file is not available in Linux 2.2 and earlier -- MTK
+#. See kernel commit edd5cd4a9424f22b0fa08bef5e299d41befd5622
#. type: Plain text
-#: build/C/man2/shmget.2:274
+#: build/C/man2/sync_file_range.2:201
msgid ""
-"System wide maximum number of shared memory segments: implementation "
-"dependent (currently 4096, was 128 before Linux 2.3.99; on Linux, this limit "
-"can be read and modified via I</proc/sys/kernel/shmmni>)."
+"Some architectures (e.g., PowerPC, ARM) need 64-bit arguments to be aligned "
+"in a suitable pair of registers. On such architectures, the call signature "
+"of B<sync_file_range>() shown in the SYNOPSIS would force a register to be "
+"wasted as padding between the I<fd> and I<offset> arguments. (See "
+"B<syscall>(2) for details.) Therefore, these architectures define a "
+"different system call that orders the arguments suitably:"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:278
+#: build/C/man2/sync_file_range.2:206
+#, no-wrap
msgid ""
-"The implementation has no specific limits for the per-process maximum number "
-"of shared memory segments (B<SHMSEG>)."
+"B<int sync_file_range2(int >I<fd>B<, unsigned int >I<flags>B<,>\n"
+"B< off64_t >I<offset>B<, off64_t >I<nbytes>B<);>\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:284
+#: build/C/man2/sync_file_range.2:211
msgid ""
-"Until version 2.3.30 Linux would return B<EIDRM> for a B<shmget>() on a "
-"shared memory segment scheduled for deletion."
+"The behavior of this system call is otherwise exactly the same as "
+"B<sync_file_range>()."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:290
+#: build/C/man2/sync_file_range.2:222
msgid ""
-"The name choice B<IPC_PRIVATE> was perhaps unfortunate, B<IPC_NEW> would "
-"more clearly show its function."
+"A system call with this signature first appeared on the ARM architecture in "
+"Linux 2.6.20, with the name B<arm_sync_file_range>(). It was renamed in "
+"Linux 2.6.22, when the analogous system call was added for PowerPC. On "
+"architectures where glibc support is provided, glibc transparently wraps "
+"B<sync_file_range2>() under the name B<sync_file_range>()."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmget.2:297
-msgid ""
-"B<shmat>(2), B<shmctl>(2), B<shmdt>(2), B<ftok>(3), B<capabilities>(7), "
-"B<shm_overview>(7), B<svipc>(7)"
+#: build/C/man2/sync_file_range.2:227
+msgid "B<fdatasync>(2), B<fsync>(2), B<msync>(2), B<sync>(2)"
msgstr ""
#. type: TH
-#: build/C/man2/shmop.2:39
+#: build/C/man2/memfd_create.2:21
#, no-wrap
-msgid "SHMOP"
+msgid "MEMFD_CREATE"
msgstr ""
-#. type: TH
-#: build/C/man2/shmop.2:39
-#, no-wrap
-msgid "2008-06-03"
+#. type: Plain text
+#: build/C/man2/memfd_create.2:24
+msgid "memfd_create - create an anonymous file"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmop.2:42
-msgid "shmat, shmdt - shared memory operations"
+#: build/C/man2/memfd_create.2:26
+msgid "B<#include E<lt>sys/memfd.hE<gt>>"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmop.2:46
-#, no-wrap
-msgid ""
-"B<#include E<lt>sys/types.hE<gt>>\n"
-"B<#include E<lt>sys/shm.hE<gt>>\n"
+#: build/C/man2/memfd_create.2:28
+msgid "B<int memfd_create(const char *>I<name>B<, unsigned int >I<flags>B<);>"
msgstr ""
+#. David Herrmann:
+#. memfd uses VM_NORESERVE so each page is accounted on first access.
+#. This means, the overcommit-limits (see __vm_enough_memory()) and the
+#. memory-cgroup limits (mem_cgroup_try_charge()) are applied. Note that
+#. those are accounted on "current" and "current->mm", that is, the
+#. process doing the first page access.
#. type: Plain text
-#: build/C/man2/shmop.2:48
-#, no-wrap
+#: build/C/man2/memfd_create.2:51
msgid ""
-"B<void *shmat(int >I<shmid>B<, const void *>I<shmaddr>B<, int "
-">I<shmflg>B<);>\n"
+"B<memfd_create>() creates an anonymous file and returns a file descriptor "
+"that refers to it. The file behaves like a regular file, and so can be "
+"modified, truncated, memory-mapped, and so on. However, unlike a regular "
+"file, it lives in RAM and has a volatile backing storage. Once all "
+"references to the file are dropped, it is automatically released. Anonymous "
+"memory is used for all backing pages of the file. Therefore, files created "
+"by B<memfd_create>() have the same semantics as other anonymous memory "
+"allocations such as those allocated using B<mmap>(2) with the "
+"B<MAP_ANONYMOUS> flag."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmop.2:50
-#, no-wrap
-msgid "B<int shmdt(const void *>I<shmaddr>B<);>\n"
+#: build/C/man2/memfd_create.2:58
+msgid ""
+"The initial size of the file is set to 0. Following the call, the file size "
+"should be set using B<ftruncate>(2). (Alternatively, the file may be "
+"populated by calls to B<write>(2) or similar.)"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmop.2:59
+#: build/C/man2/memfd_create.2:69
msgid ""
-"B<shmat>() attaches the shared memory segment identified by I<shmid> to the "
-"address space of the calling process. The attaching address is specified by "
-"I<shmaddr> with one of the following criteria:"
+"The name supplied in I<name> is used as a filename and will be displayed as "
+"the target of the corresponding symbolic link in the directory "
+"I</proc/self/fd/>. The displayed name is always prefixed with I<memfd:> and "
+"serves only for debugging purposes. Names do not affect the behavior of the "
+"file descriptor, and as such multiple files can have the same name without "
+"any side effects."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmop.2:65
+#: build/C/man2/memfd_create.2:74
msgid ""
-"If I<shmaddr> is NULL, the system chooses a suitable (unused) address at "
-"which to attach the segment."
+"The following values may be bitwise ORed in I<flags> to change the behaviour "
+"of B<memfd_create>():"
msgstr ""
-#. type: Plain text
-#: build/C/man2/shmop.2:80
-msgid ""
-"If I<shmaddr> isn't NULL and B<SHM_RND> is specified in I<shmflg>, the "
-"attach occurs at the address equal to I<shmaddr> rounded down to the nearest "
-"multiple of B<SHMLBA>. Otherwise I<shmaddr> must be a page-aligned address "
-"at which the attach occurs."
+#. type: TP
+#: build/C/man2/memfd_create.2:74
+#, no-wrap
+msgid "B<MFD_CLOEXEC>"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmop.2:90
+#: build/C/man2/memfd_create.2:84
msgid ""
-"If B<SHM_RDONLY> is specified in I<shmflg>, the segment is attached for "
-"reading and the process must have read permission for the segment. "
-"Otherwise the segment is attached for read and write and the process must "
-"have read and write permission for the segment. There is no notion of a "
-"write-only shared memory segment."
+"Set the close-on-exec (B<FD_CLOEXEC>) flag on the new file descriptor. See "
+"the description of the B<O_CLOEXEC> flag in B<open>(2) for reasons why this "
+"may be useful."
msgstr ""
-#. type: Plain text
-#: build/C/man2/shmop.2:105
-msgid ""
-"The (Linux-specific) B<SHM_REMAP> flag may be specified in I<shmflg> to "
-"indicate that the mapping of the segment should replace any existing mapping "
-"in the range starting at I<shmaddr> and continuing for the size of the "
-"segment. (Normally an B<EINVAL> error would result if a mapping already "
-"exists in this address range.) In this case, I<shmaddr> must not be NULL."
+#. type: TP
+#: build/C/man2/memfd_create.2:84
+#, no-wrap
+msgid "B<MFD_ALLOW_SEALING>"
msgstr ""
+#. FIXME Why is the MFD_ALLOW_SEALING behavior not simply the default?
+#. Is it worth adding some text explaining this?
#. type: Plain text
-#: build/C/man2/shmop.2:112
+#: build/C/man2/memfd_create.2:100
msgid ""
-"The B<brk>(2) value of the calling process is not altered by the attach. "
-"The segment will automatically be detached at process exit. The same "
-"segment may be attached as a read and as a read-write one, and more than "
-"once, in the process's address space."
+"Allow sealing operations on this file. See the discussion of the "
+"B<F_ADD_SEALS> and B<F_GET_SEALS> operations in B<fcntl>(2), and also NOTES, "
+"below. The initial set of seals is empty. If this flag is not set, the "
+"initial set of seals will be B<F_SEAL_SEAL>, meaning that no other seals can "
+"be set on the file."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmop.2:120
-msgid ""
-"A successful B<shmat>() call updates the members of the I<shmid_ds> "
-"structure (see B<shmctl>(2)) associated with the shared memory segment as "
-"follows:"
+#: build/C/man2/memfd_create.2:104
+msgid "Unused bits in I<flags> must be 0."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmop.2:123
-msgid "I<shm_atime> is set to the current time."
+#: build/C/man2/memfd_create.2:113
+msgid ""
+"As its return value, B<memfd_create>() returns a new file descriptor that "
+"can be used to refer to the file. This file descriptor is opened for both "
+"reading and writing (B<O_RDWR>) and B<O_LARGEFILE> is set for the "
+"descriptor."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmop.2:126 build/C/man2/shmop.2:152
-msgid "I<shm_lpid> is set to the process-ID of the calling process."
+#: build/C/man2/memfd_create.2:126
+msgid ""
+"With respect to B<fork>(2) and B<execve>(2), the usual semantics apply for "
+"the file descriptor created by B<memfd_create>(). A copy of the file "
+"descriptor is inherited by the child produced by B<fork>(2) and refers to "
+"the same file. The file descriptor is preserved across B<execve>(2), unless "
+"the close-on-exec flag has been set."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmop.2:129
-msgid "I<shm_nattch> is incremented by one."
+#: build/C/man2/memfd_create.2:133
+msgid ""
+"On success, B<memfd_create>() returns a new file descriptor. On error, -1 "
+"is returned and I<errno> is set to indicate the error."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmop.2:140
-msgid ""
-"B<shmdt>() detaches the shared memory segment located at the address "
-"specified by I<shmaddr> from the address space of the calling process. The "
-"to-be-detached segment must be currently attached with I<shmaddr> equal to "
-"the value returned by the attaching B<shmat>() call."
+#: build/C/man2/memfd_create.2:139
+msgid "The address in I<name> points to invalid memory."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmop.2:146
+#: build/C/man2/memfd_create.2:146
msgid ""
-"On a successful B<shmdt>() call the system updates the members of the "
-"I<shmid_ds> structure associated with the shared memory segment as follows:"
+"An unsupported value was specified in one of the arguments: I<flags> "
+"included unknown bits, or I<name> was too long."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmop.2:149
-msgid "I<shm_dtime> is set to the current time."
+#: build/C/man2/memfd_create.2:149
+msgid "The per-process limit on open file descriptors has been reached."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmop.2:157
-msgid ""
-"I<shm_nattch> is decremented by one. If it becomes 0 and the segment is "
-"marked for deletion, the segment is deleted."
+#: build/C/man2/memfd_create.2:152
+msgid "The system-wide limit on the total number of open files has been reached."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmop.2:161
-msgid "After a B<fork>(2) the child inherits the attached shared memory segments."
+#: build/C/man2/memfd_create.2:155
+msgid "There was insufficient memory to create a new anonymous file."
msgstr ""
+#. FIXME . When glibc support appears, update the following sentence:
#. type: Plain text
-#: build/C/man2/shmop.2:165
+#: build/C/man2/memfd_create.2:161
msgid ""
-"After an B<execve>(2) all attached shared memory segments are detached from "
-"the process."
+"The B<memfd_create>() system call first appeared in Linux 3.17. Support in "
+"the GNU C library is pending."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmop.2:169
-msgid ""
-"Upon B<_exit>(2) all attached shared memory segments are detached from the "
-"process."
+#: build/C/man2/memfd_create.2:165
+msgid "The B<memfd_create>() system call is Linux-specific."
msgstr ""
+#. See also http://lwn.net/Articles/593918/
+#. and http://lwn.net/Articles/594919/ and http://lwn.net/Articles/591108/
#. type: Plain text
-#: build/C/man2/shmop.2:177
+#: build/C/man2/memfd_create.2:178
msgid ""
-"On success B<shmat>() returns the address of the attached shared memory "
-"segment; on error I<(void\\ *)\\ -1> is returned, and I<errno> is set to "
-"indicate the cause of the error."
+"The B<memfd_create>() system call provides a simple alternative to manually "
+"mounting a I<tmpfs> filesystem and creating and opening a file in that "
+"filesystem. The primary purpose of B<memfd_create>() is to create files "
+"and associated file descriptors that are used with the file-sealing APIs "
+"provided by B<fcntl>(2)."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmop.2:183
+#: build/C/man2/memfd_create.2:192
msgid ""
-"On success B<shmdt>() returns 0; on error -1 is returned, and I<errno> is "
-"set to indicate the cause of the error."
+"The B<memfd_create>() system call also has uses without file sealing (which "
+"is why file-sealing is disabled, unless explicitly requested with the "
+"B<MFD_ALLOW_SEALING> flag). In particular, it can be used as an alternative "
+"to creating files in I<tmp> or as an alternative to using the B<open>(2) "
+"B<O_TMPFILE> in cases where there is no intention to actually link the "
+"resulting file into the filesystem."
msgstr ""
-#. type: Plain text
-#: build/C/man2/shmop.2:189
-msgid "When B<shmat>() fails, I<errno> is set to one of the following:"
+#. type: SS
+#: build/C/man2/memfd_create.2:192
+#, no-wrap
+msgid "File sealing"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmop.2:195
+#: build/C/man2/memfd_create.2:210
msgid ""
-"The calling process does not have the required permissions for the requested "
-"attach type, and does not have the B<CAP_IPC_OWNER> capability."
+"In the absence of file sealing, processes that communicate via shared memory "
+"must either trust each other, or take measures to deal with the possibility "
+"that an untrusted peer may manipulate the shared memory region in "
+"problematic ways. For example, an untrusted peer might modify the contents "
+"of the shared memory at any time, or shrink the shared memory region. The "
+"former possibility leaves the local process vulnerable to "
+"time-of-check-to-time-of-use race conditions (typically dealt with by "
+"copying data from the shared memory region before checking and using it). "
+"The latter possibility leaves the local process vulnerable to B<SIGBUS> "
+"signals when an attempt is made to access a now-nonexistent location in the "
+"shared memory region. (Dealing with this possibility necessitates the use "
+"of a handler for the B<SIGBUS> signal.)"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmop.2:209
+#: build/C/man2/memfd_create.2:216
msgid ""
-"Invalid I<shmid> value, unaligned (i.e., not page-aligned and B<SHM_RND> was "
-"not specified) or invalid I<shmaddr> value, or can't attach segment at "
-"I<shmaddr>, or B<SHM_REMAP> was specified and I<shmaddr> was NULL."
+"Dealing with untrusted peers imposes extra complexity on code that employs "
+"shared memory. Memory sealing enables that extra complexity to be "
+"eliminated, by allowing a process to operate secure in the knowledge that "
+"its peer can't modify the shared memory in an undesired fashion."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmop.2:212
-msgid "Could not allocate memory for the descriptor or for the page tables."
-msgstr ""
-
-#. type: Plain text
-#: build/C/man2/shmop.2:218
-msgid "When B<shmdt>() fails, I<errno> is set as follows:"
+#: build/C/man2/memfd_create.2:218
+msgid "An example of the usage of the sealing mechanism is as follows:"
msgstr ""
-#. The following since 2.6.17-rc1:
#. type: Plain text
-#: build/C/man2/shmop.2:226
+#: build/C/man2/memfd_create.2:225
msgid ""
-"There is no shared memory segment attached at I<shmaddr>; or, I<shmaddr> is "
-"not aligned on a page boundary."
+"The first process creates a I<tmpfs> file using B<memfd_create>(). The call "
+"yields a file descriptor used in subsequent steps."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmop.2:245
+#: build/C/man2/memfd_create.2:232
msgid ""
-"In SVID 3 (or perhaps earlier) the type of the I<shmaddr> argument was "
-"changed from I<char *> into I<const void *>, and the returned type of "
-"B<shmat>() from I<char *> into I<void *>. (Linux libc4 and libc5 have the "
-"I<char *> prototypes; glibc2 has I<void *>.)"
+"The first process sizes the file created in the previous step using "
+"B<ftruncate>(2), maps it using B<mmap>(2), and populates the shared memory "
+"with the desired data."
msgstr ""
-#. type: Plain text
-#: build/C/man2/shmop.2:257
-msgid ""
-"Using B<shmat>() with I<shmaddr> equal to NULL is the preferred, portable "
-"way of attaching a shared memory segment. Be aware that the shared memory "
-"segment attached in this way may be attached at different addresses in "
-"different processes. Therefore, any pointers maintained within the shared "
-"memory must be made relative (typically to the starting address of the "
-"segment), rather than absolute."
+#. type: IP
+#: build/C/man2/memfd_create.2:232
+#, no-wrap
+msgid "3."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmop.2:262
+#: build/C/man2/memfd_create.2:242
msgid ""
-"On Linux, it is possible to attach a shared memory segment even if it is "
-"already marked to be deleted. However, POSIX.1-2001 does not specify this "
-"behavior and many other implementations do not support it."
-msgstr ""
-
-#. type: Plain text
-#: build/C/man2/shmop.2:265
-msgid "The following system parameter affects B<shmat>():"
+"The first process uses the B<fcntl>(2) B<F_ADD_SEALS> operation to place "
+"one or more seals on the file, in order to restrict further modifications on "
+"the file. (If placing the seal B<F_SEAL_WRITE>, then it will be necessary "
+"to first unmap the shared writable mapping created in the previous step.)"
msgstr ""
-#. FIXME A good explanation of the rationale for the existence
-#. of SHMLBA would be useful here
-#. type: TP
-#: build/C/man2/shmop.2:265
+#. type: IP
+#: build/C/man2/memfd_create.2:242
#, no-wrap
-msgid "B<SHMLBA>"
+msgid "4."
msgstr ""
-#. FIXME That last sentence isn't true for all Linux
-#. architectures (i.e., SHMLBA != PAGE_SIZE for some architectures)
-#. -- MTK, Nov 04
#. type: Plain text
-#: build/C/man2/shmop.2:278
+#: build/C/man2/memfd_create.2:247
msgid ""
-"Segment low boundary address multiple. Must be page aligned. For the "
-"current implementation the B<SHMLBA> value is B<PAGE_SIZE>."
+"A second process obtains a file descriptor for the I<tmpfs> file and maps "
+"it. Among the possible ways in which this could happen are the following:"
msgstr ""
#. type: Plain text
-#: build/C/man2/shmop.2:282
+#: build/C/man2/memfd_create.2:258
msgid ""
-"The implementation places no intrinsic limit on the per-process maximum "
-"number of shared memory segments (B<SHMSEG>)."
+"The process that called B<memfd_create>() could transfer the resulting file "
+"descriptor to the second process via a UNIX domain socket (see B<unix>(7) "
+"and B<cmsg>(3)). The second process then maps the file using B<mmap>(2)."
msgstr ""
#. type: Plain text
-#: build/C/man2/shmop.2:289
+#: build/C/man2/memfd_create.2:266
msgid ""
-"B<brk>(2), B<mmap>(2), B<shmctl>(2), B<shmget>(2), B<capabilities>(7), "
-"B<shm_overview>(7), B<svipc>(7)"
-msgstr ""
-
-#. type: TH
-#: build/C/man2/subpage_prot.2:28
-#, no-wrap
-msgid "SUBPAGE_PROT"
-msgstr ""
-
-#. type: TH
-#: build/C/man2/subpage_prot.2:28
-#, no-wrap
-msgid "2010-10-30"
+"The second process is created via B<fork>(2) and thus automatically "
+"inherits the file descriptor and mapping. (Note that in this case and the "
+"next, there is a natural trust relationship between the two processes, since "
+"they are running under the same user ID. Therefore, file sealing would not "
+"normally be necessary.)"
msgstr ""
#. type: Plain text
-#: build/C/man2/subpage_prot.2:31
-msgid "subpage_prot - define a subpage protection for an address range"
+#: build/C/man2/memfd_create.2:280
+msgid ""
+"The second process opens the file I</proc/E<lt>pdE<gt>/fd/E<lt>fdE<gt>>, "
+"where I<E<lt>pidE<gt>> is the PID of the first process (the one that called "
+"B<memfd_create>()), and I<E<lt>fdE<gt>> is the number of the file descriptor "
+"returned by the call to B<memfd_create>() in that process. The second "
+"process then maps the file using B<mmap>(2)."
msgstr ""
-#. type: Plain text
-#: build/C/man2/subpage_prot.2:35
-#, no-wrap
-msgid ""
-"B<long subpage_prot(unsigned long >I<addr>B<, unsigned long >I<len>B<,>\n"
-"B< uint32_t *>I<map>B<);>\n"
+#. type: IP
+#: build/C/man2/memfd_create.2:281
+#, no-wrap
+msgid "5."
msgstr ""
#. type: Plain text
-#: build/C/man2/subpage_prot.2:42
+#: build/C/man2/memfd_create.2:293
msgid ""
-"The PowerPC-specific B<subpage_prot>() system call provides the facility to "
-"control the access permissions on individual 4kB subpages on systems "
-"configured with a page size of 64kB."
+"The second process uses the B<fcntl>(2) B<F_GET_SEALS> operation to "
+"retrieve the bit mask of seals that has been applied to the file. This bit "
+"mask can be inspected in order to determine what kinds of restrictions have "
+"been placed on file modifications. If desired, the second process can apply "
+"further seals to impose additional restrictions (so long as the "
+"B<F_SEAL_SEAL> seal has not yet been applied)."
msgstr ""
#. type: Plain text
-#: build/C/man2/subpage_prot.2:49
+#: build/C/man2/memfd_create.2:297
msgid ""
-"The protection map is applied to the memory pages in the region starting at "
-"I<addr> and continuing for I<len> bytes. Both of these arguments must be "
-"aligned to a 64-kB boundary."
+"Below are shown two example programs that demonstrate the use of "
+"B<memfd_create>() and the file sealing API."
msgstr ""
#. type: Plain text
-#: build/C/man2/subpage_prot.2:61
+#: build/C/man2/memfd_create.2:312
msgid ""
-"The protection map is specified in the buffer pointed to by I<map>. The map "
-"has 2 bits per 4kB subpage; thus each 32-bit word specifies the protections "
-"of 16 4kB subpages inside a 64kB page (so, the number of 32-bit words "
-"pointed to by I<map> should equate to the number of 64-kB pages specified by "
-"I<len>). Each 2-bit field in the protection map is either 0 to allow any "
-"access, 1 to prevent writes, or 2 or 3 to prevent all accesses."
+"The first program, I<t_memfd_create.c>, creates a I<tmpfs> file using "
+"B<memfd_create>(), sets a size for the file, maps it into memory, and "
+"optionally places some seals on the file. The program accepts up to three "
+"command-line arguments, of which the first two are required. The first "
+"argument is the name to associate with the file, the second argument is the "
+"size to be set for the file, and the optional third is a string of "
+"characters that specify seals to be set on file."
msgstr ""
#. type: Plain text
-#: build/C/man2/subpage_prot.2:66
+#: build/C/man2/memfd_create.2:318
msgid ""
-"On success, B<subpage_prot>() returns 0. Otherwise, one of the error codes "
-"specified below is returned."
+"The second program, I<t_get_seals.c>, can be used to open an existing file "
+"that was created via B<memfd_create>() and inspect the set of seals that "
+"have been applied to that file."
msgstr ""
#. type: Plain text
-#: build/C/man2/subpage_prot.2:72
-msgid "The buffer referred to by I<map> is not accessible."
-msgstr ""
-
-#. type: Plain text
-#: build/C/man2/subpage_prot.2:82
+#: build/C/man2/memfd_create.2:323
msgid ""
-"The I<addr> or I<len> arguments are incorrect. Both of these arguments must "
-"be aligned to a multiple of the system page size, and they must not refer to "
-"a region outside of the address space of the process or to a region that "
-"consists of huge pages."
+"The following shell session demonstrates the use of these programs. First "
+"we create a I<tmpfs> file and set some seals on it:"
msgstr ""
#. type: Plain text
-#: build/C/man2/subpage_prot.2:85 build/C/man2/sync_file_range.2:166
-msgid "Out of memory."
+#: build/C/man2/memfd_create.2:329
+#, no-wrap
+msgid ""
+"$ B<./t_memfd_create my_memfd_file 4096 sw &>\n"
+"[1] 11775\n"
+"PID: 11775; fd: 3; /proc/11775/fd/3\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/subpage_prot.2:91
+#: build/C/man2/memfd_create.2:347
msgid ""
-"This system call is provided on the PowerPC architecture since Linux "
-"2.6.25. The system call is provided only if the kernel is configured with "
-"B<CONFIG_PPC_64K_PAGES>. No library support is provided."
+"At this point, the I<t_memfd_create> program continues to run in the "
+"background. From another program, we can obtain a file descriptor for the "
+"file created by B<memfd_create>() by opening the I</proc/PID/fd> file that "
+"corresponds to the descriptor opened by B<memfd_create>(). Using that "
+"pathname, we inspect the content of the I</proc/PID/fd> symbolic link, and "
+"use our I<t_get_seals> program to view the seals that have been placed on "
+"the file:"
msgstr ""
#. type: Plain text
-#: build/C/man2/subpage_prot.2:98
+#: build/C/man2/memfd_create.2:354
+#, no-wrap
msgid ""
-"Normal page protections (at the 64-kB page level) also apply; the subpage "
-"protection mechanism is an additional constraint, so putting 0 in a 2-bit "
-"field won't allow writes to a page that is otherwise write-protected."
+"$ B<readlink /proc/11775/fd/3>\n"
+"/memfd:my_memfd_file (deleted)\n"
+"$ B<./t_get_seals /proc/11775/fd/3>\n"
+"Existing seals: WRITE SHRINK\n"
msgstr ""
#. type: SS
-#: build/C/man2/subpage_prot.2:98
+#: build/C/man2/memfd_create.2:356
#, no-wrap
-msgid "Rationale"
+msgid "Program source: t_memfd_create.c"
msgstr ""
-#. In the initial implementation, it was the case that:
-#. In fact the whole process is switched to use 4k hardware pages when the
-#. subpage_prot system call is used, but this could be improved in future
-#. to switch only the affected segments.
-#. But Paul Mackerass says (Oct 2010): I'm pretty sure we now only switch
-#. the affected segment, not the whole process.
#. type: Plain text
-#: build/C/man2/subpage_prot.2:120
+#: build/C/man2/memfd_create.2:365
+#, no-wrap
msgid ""
-"This system call is provided to assist writing emulators that operate using "
-"64-kB pages on PowerPC systems. When emulating systems such as x86, which "
-"uses a smaller page size, the emulator can no longer use the "
-"memory-management unit (MMU) and normal system calls for controlling page "
-"protections. (The emulator could emulate the MMU by checking and possibly "
-"remapping the address for each memory access in software, but that is slow.) "
-"The idea is that the emulator supplies an array of protection masks to apply "
-"to a specified range of virtual addresses. These masks are applied at the "
-"level where hardware page-table entries (PTEs) are inserted into the "
-"hardware page table based on the Linux PTEs, so the Linux PTEs are not "
-"affected. Implicit in this is that the regions of the address space that "
-"are protected are switched to use 4-kB hardware pages rather than 64-kB "
-"hardware pages (on machines with hardware 64-kB page support)."
+"#include E<lt>sys/memfd.hE<gt>\n"
+"#include E<lt>fcntl.hE<gt>\n"
+"#include E<lt>stdlib.hE<gt>\n"
+"#include E<lt>unistd.hE<gt>\n"
+"#include E<lt>string.hE<gt>\n"
+"#include E<lt>stdio.hE<gt>\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/subpage_prot.2:123
-msgid "B<mprotect>(2), B<syscall>(2);"
+#: build/C/man2/memfd_create.2:377
+#, no-wrap
+msgid ""
+"int\n"
+"main(int argc, char *argv[])\n"
+"{\n"
+" int fd;\n"
+" unsigned int seals;\n"
+" char *addr;\n"
+" char *name, *seals_arg;\n"
+" ssize_t len;\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/subpage_prot.2:125
-msgid "the kernel source file I<Documentation/vm/hugetlbpage.txt>."
-msgstr ""
-
-#. type: TH
-#: build/C/man2/sync_file_range.2:30
+#: build/C/man2/memfd_create.2:388
#, no-wrap
-msgid "SYNC_FILE_RANGE"
+msgid ""
+" if (argc E<lt> 3) {\n"
+" fprintf(stderr, \"%s name size [seals]\\en\", argv[0]);\n"
+" fprintf(stderr, \"\\et\\(aqseals\\(aq can contain any of the \"\n"
+" \"following characters:\\en\");\n"
+" fprintf(stderr, \"\\et\\etg - F_SEAL_GROW\\en\");\n"
+" fprintf(stderr, \"\\et\\ets - F_SEAL_SHRINK\\en\");\n"
+" fprintf(stderr, \"\\et\\etw - F_SEAL_WRITE\\en\");\n"
+" fprintf(stderr, \"\\et\\etS - F_SEAL_SEAL\\en\");\n"
+" exit(EXIT_FAILURE);\n"
+" }\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:33
-msgid "sync_file_range - sync a file segment with disk"
+#: build/C/man2/memfd_create.2:392
+#, no-wrap
+msgid ""
+" name = argv[1];\n"
+" len = atoi(argv[2]);\n"
+" seals_arg = argv[3];\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:37
+#: build/C/man2/memfd_create.2:395
#, no-wrap
msgid ""
-"B<#define _GNU_SOURCE> /* See feature_test_macros(7) */\n"
-"B<#include E<lt>fcntl.hE<gt>>\n"
+" /* Create an anonymous file in tmpfs; allow seals to be\n"
+" placed on the file */\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:40
+#: build/C/man2/memfd_create.2:399
#, no-wrap
msgid ""
-"B<int sync_file_range(int >I<fd>B<, off64_t >I<offset>B<, off64_t "
-">I<nbytes>B<,>\n"
-"B< unsigned int >I<flags>B<);>\n"
+" fd = memfd_create(name, MFD_ALLOW_SEALING);\n"
+" if (fd == -1)\n"
+" errExit(\"memfd_create\");\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:47
-msgid ""
-"B<sync_file_range>() permits fine control when synchronizing the open file "
-"referred to by the file descriptor I<fd> with disk."
+#: build/C/man2/memfd_create.2:401
+#, no-wrap
+msgid " /* Size the file as specified on the command line */\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:61
+#: build/C/man2/memfd_create.2:404
+#, no-wrap
msgid ""
-"I<offset> is the starting byte of the file range to be synchronized. "
-"I<nbytes> specifies the length of the range to be synchronized, in bytes; if "
-"I<nbytes> is zero, then all bytes from I<offset> through to the end of file "
-"are synchronized. Synchronization is in units of the system page size: "
-"I<offset> is rounded down to a page boundary; I<(offset+nbytes-1)> is "
-"rounded up to a page boundary."
+" if (ftruncate(fd, len) == -1)\n"
+" errExit(\"truncate\");\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:65
-msgid "The I<flags> bit-mask argument can include any of the following values:"
+#: build/C/man2/memfd_create.2:407
+#, no-wrap
+msgid ""
+" printf(\"PID: %ld; fd: %d; /proc/%ld/fd/%d\\en\",\n"
+" (long) getpid(), fd, (long) getpid(), fd);\n"
msgstr ""
-#. type: TP
-#: build/C/man2/sync_file_range.2:65
+#. type: Plain text
+#: build/C/man2/memfd_create.2:410
#, no-wrap
-msgid "B<SYNC_FILE_RANGE_WAIT_BEFORE>"
+msgid ""
+" /* Code to map the file and populate the mapping with data\n"
+" omitted */\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:70
+#: build/C/man2/memfd_create.2:413
+#, no-wrap
msgid ""
-"Wait upon write-out of all pages in the specified range that have already "
-"been submitted to the device driver for write-out before performing any "
-"write."
+" /* If a \\(aqseals\\(aq command-line argument was supplied, set some\n"
+" seals on the file */\n"
msgstr ""
-#. type: TP
-#: build/C/man2/sync_file_range.2:70 build/C/man2/sync_file_range.2:120
+#. type: Plain text
+#: build/C/man2/memfd_create.2:416
#, no-wrap
-msgid "B<SYNC_FILE_RANGE_WRITE>"
+msgid ""
+" if (seals_arg != NULL) {\n"
+" seals = 0;\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:76
+#: build/C/man2/memfd_create.2:425
+#, no-wrap
msgid ""
-"Initiate write-out of all dirty pages in the specified range which are not "
-"presently submitted write-out. Note that even this may block if you attempt "
-"to write more than request queue size."
+" if (strchr(seals_arg, \\(aqg\\(aq) != NULL)\n"
+" seals |= F_SEAL_GROW;\n"
+" if (strchr(seals_arg, \\(aqs\\(aq) != NULL)\n"
+" seals |= F_SEAL_SHRINK;\n"
+" if (strchr(seals_arg, \\(aqw\\(aq) != NULL)\n"
+" seals |= F_SEAL_WRITE;\n"
+" if (strchr(seals_arg, \\(aqS\\(aq) != NULL)\n"
+" seals |= F_SEAL_SEAL;\n"
msgstr ""
-#. type: TP
-#: build/C/man2/sync_file_range.2:76
+#. type: Plain text
+#: build/C/man2/memfd_create.2:429
#, no-wrap
-msgid "B<SYNC_FILE_RANGE_WAIT_AFTER>"
+msgid ""
+" if (fcntl(fd, F_ADD_SEALS, seals) == -1)\n"
+" errExit(\"fcntl\");\n"
+" }\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:80
-msgid "Wait upon write-out of all pages in the range after performing any write."
+#: build/C/man2/memfd_create.2:432
+#, no-wrap
+msgid ""
+" /* Keep running, so that the file created by memfd_create()\n"
+" continues to exist */\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:84
-msgid "Specifying I<flags> as 0 is permitted, as a no-op."
+#: build/C/man2/memfd_create.2:434
+#, no-wrap
+msgid " pause();\n"
msgstr ""
#. type: SS
-#: build/C/man2/sync_file_range.2:84
+#: build/C/man2/memfd_create.2:438
#, no-wrap
-msgid "Warning"
+msgid "Program source: t_get_seals.c"
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:100
+#: build/C/man2/memfd_create.2:447
+#, no-wrap
msgid ""
-"This system call is extremely dangerous and should not be used in portable "
-"programs. None of these operations writes out the file's metadata. "
-"Therefore, unless the application is strictly performing overwrites of "
-"already-instantiated disk blocks, there are no guarantees that the data will "
-"be available after a crash. There is no user interface to know if a write "
-"is purely an overwrite. On file systems using copy-on-write semantics "
-"(e.g., I<btrfs>) an overwrite of existing allocated blocks is impossible. "
-"When writing into preallocated space, many file systems also require calls "
-"into the block allocator, which this system call does not sync out to disk. "
-"This system call does not flush disk write caches and thus does not provide "
-"any data integrity on systems with volatile disk write caches."
+"#include E<lt>sys/memfd.hE<gt>\n"
+"#include E<lt>fcntl.hE<gt>\n"
+"#include E<lt>unistd.hE<gt>\n"
+"#include E<lt>stdlib.hE<gt>\n"
+"#include E<lt>string.hE<gt>\n"
+"#include E<lt>stdio.hE<gt>\n"
msgstr ""
-#. type: SS
-#: build/C/man2/sync_file_range.2:100
+#. type: Plain text
+#: build/C/man2/memfd_create.2:456
#, no-wrap
-msgid "Some details"
+msgid ""
+"int\n"
+"main(int argc, char *argv[])\n"
+"{\n"
+" int fd;\n"
+" unsigned int seals;\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:108
+#: build/C/man2/memfd_create.2:461
+#, no-wrap
msgid ""
-"B<SYNC_FILE_RANGE_WAIT_BEFORE> and B<SYNC_FILE_RANGE_WAIT_AFTER> will detect "
-"any I/O errors or B<ENOSPC> conditions and will return these to the caller."
+" if (argc != 2) {\n"
+" fprintf(stderr, \"%s /proc/PID/fd/FD\\en\", argv[0]);\n"
+" exit(EXIT_FAILURE);\n"
+" }\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:112
-msgid "Useful combinations of the I<flags> bits are:"
+#: build/C/man2/memfd_create.2:465
+#, no-wrap
+msgid ""
+" fd = open(argv[1], O_RDWR);\n"
+" if (fd == -1)\n"
+" errExit(\"open\");\n"
msgstr ""
-#. type: TP
-#: build/C/man2/sync_file_range.2:112
+#. type: Plain text
+#: build/C/man2/memfd_create.2:469
#, no-wrap
-msgid "B<SYNC_FILE_RANGE_WAIT_BEFORE | SYNC_FILE_RANGE_WRITE>"
+msgid ""
+" seals = fcntl(fd, F_GET_SEALS);\n"
+" if (seals == -1)\n"
+" errExit(\"fcntl\");\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:120
+#: build/C/man2/memfd_create.2:480
+#, no-wrap
msgid ""
-"Ensures that all pages in the specified range which were dirty when "
-"B<sync_file_range>() was called are placed under write-out. This is a "
-"start-write-for-data-integrity operation."
+" printf(\"Existing seals:\");\n"
+" if (seals & F_SEAL_SEAL)\n"
+" printf(\" SEAL\");\n"
+" if (seals & F_SEAL_GROW)\n"
+" printf(\" GROW\");\n"
+" if (seals & F_SEAL_WRITE)\n"
+" printf(\" WRITE\");\n"
+" if (seals & F_SEAL_SHRINK)\n"
+" printf(\" SHRINK\");\n"
+" printf(\"\\en\");\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:127
+#: build/C/man2/memfd_create.2:483
+#, no-wrap
msgid ""
-"Start write-out of all dirty pages in the specified range which are not "
-"presently under write-out. This is an asynchronous flush-to-disk "
-"operation. This is not suitable for data integrity operations."
+" /* Code to map the file and access the contents of the\n"
+" resulting mapping omitted */\n"
msgstr ""
-#. type: TP
-#: build/C/man2/sync_file_range.2:127
+#. type: Plain text
+#: build/C/man2/memfd_create.2:493
+msgid "B<fcntl>(2), B<ftruncate>(2), B<mmap>(2), B<shmget>(2), B<shm_open>(3)"
+msgstr ""
+
+#. type: TH
+#: build/C/man2/s390_pci_mmio_write.2:25
#, no-wrap
-msgid "B<SYNC_FILE_RANGE_WAIT_BEFORE> (or B<SYNC_FILE_RANGE_WAIT_AFTER>)"
+msgid "S390_PCI_MMIO_WRITE"
+msgstr ""
+
+#. type: TH
+#: build/C/man2/s390_pci_mmio_write.2:25
+#, no-wrap
+msgid "2015-01-15"
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:134
+#: build/C/man2/s390_pci_mmio_write.2:29
msgid ""
-"Wait for completion of write-out of all pages in the specified range. This "
-"can be used after an earlier B<SYNC_FILE_RANGE_WAIT_BEFORE | "
-"SYNC_FILE_RANGE_WRITE> operation to wait for completion of that operation, "
-"and obtain its result."
+"s390_pci_mmio_write, s390_pci_mmio_read - transfer data to/from PCI MMIO "
+"memory page"
msgstr ""
-#. type: TP
-#: build/C/man2/sync_file_range.2:134
+#. type: Plain text
+#: build/C/man2/s390_pci_mmio_write.2:32
#, no-wrap
-msgid ""
-"B<SYNC_FILE_RANGE_WAIT_BEFORE | SYNC_FILE_RANGE_WRITE | "
-"SYNC_FILE_RANGE_WAIT_AFTER>"
+msgid "B<#include E<lt>asm/unistd.hE<gt>>\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:141
+#: build/C/man2/s390_pci_mmio_write.2:35
+#, no-wrap
msgid ""
-"This is a write-for-data-integrity operation that will ensure that all pages "
-"in the specified range which were dirty when B<sync_file_range>() was "
-"called are committed to disk."
+"B<int s390_pci_mmio_write(unsigned long >I<mmio_addr>B<,>\n"
+"B< void *>I<user_buffer>B<, size_t >I<length>B<);>\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:147
+#: build/C/man2/s390_pci_mmio_write.2:38
+#, no-wrap
msgid ""
-"On success, B<sync_file_range>() returns 0; on failure -1 is returned and "
-"I<errno> is set to indicate the error."
+"B<int s390_pci_mmio_read(unsigned long >I<mmio_addr>B<,>\n"
+"B< void *>I<user_buffer>B<, size_t >I<length>B<);>\n"
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:152
-msgid "I<fd> is not a valid file descriptor."
+#: build/C/man2/s390_pci_mmio_write.2:57
+msgid ""
+"The B<s390_pci_mmio_write>() system call writes I<length> bytes of data "
+"from the user-space buffer I<user_buffer> to the PCI MMIO memory location "
+"specified by I<mmio_addr>. The B<s390_pci_mmio_read>() system call reads "
+"I<length> bytes of data from the PCI MMIO memory location specified by "
+"I<mmio_addr> to the user-space buffer I<user_buffer>."
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:160
-msgid "I<flags> specifies an invalid bit; or I<offset> or I<nbytes> is invalid."
+#: build/C/man2/s390_pci_mmio_write.2:68
+msgid ""
+"These system calls must be used instead of the simple assignment or "
+"data-transfer operations that are used to access the PCI MMIO memory areas "
+"mapped to user space on the Linux System z platform. The address specified "
+"by I<mmio_addr> must belong to a PCI MMIO memory page mapping in the "
+"caller's address space, and the data being written or read must not cross a "
+"page boundary. The I<length> value cannot be greater than the system page "
+"size."
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:163
-msgid "I/O error."
+#: build/C/man2/s390_pci_mmio_write.2:77
+msgid ""
+"On success, B<s390_pci_mmio_write>() and B<s390_pci_mmio_read>() return "
+"0. On error, -1 is returned and I<errno> is set to one of the error codes "
+"listed below."
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:169
-msgid "Out of disk space."
+#: build/C/man2/s390_pci_mmio_write.2:83
+msgid "The address in I<mmio_addr> is invalid."
msgstr ""
-#. FIXME . (bug?) Actually, how can 'fd' refer to a symbolic link (S_ISLNK)?
-#. (In userspace at least) it isn't possible to obtain a file descriptor
-#. for a symbolic link.
#. type: Plain text
-#: build/C/man2/sync_file_range.2:177
+#: build/C/man2/s390_pci_mmio_write.2:87
msgid ""
-"I<fd> refers to something other than a regular file, a block device, a "
-"directory, or a symbolic link."
+"I<user_buffer> does not point to a valid location in the caller's address "
+"space."
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:180
-msgid "B<sync_file_range>() appeared on Linux in kernel 2.6.17."
+#: build/C/man2/s390_pci_mmio_write.2:92
+msgid "Invalid I<length> argument."
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:183
-msgid ""
-"This system call is Linux-specific, and should be avoided in portable "
-"programs."
+#: build/C/man2/s390_pci_mmio_write.2:95
+msgid "PCI support is not enabled."
msgstr ""
-#. See kernel commit edd5cd4a9424f22b0fa08bef5e299d41befd5622
#. type: Plain text
-#: build/C/man2/sync_file_range.2:196
-msgid ""
-"Some architectures (e.g., PowerPC, ARM) need 64-bit arguments to be aligned "
-"in a suitable pair of registers. On such architectures, the call signature "
-"of B<sync_file_range>() is flawed, since it forces a register to be wasted "
-"as padding between the I<fd> and I<offset> arguments. Therefore, these "
-"architectures define a different system call that orders the arguments "
-"suitably:"
+#: build/C/man2/s390_pci_mmio_write.2:98
+msgid "Insufficient memory."
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:201
-#, no-wrap
-msgid ""
-"B<int sync_file_range2(int >I<fd>B<, unsigned int >I<flags>B<,>\n"
-"B< off64_t >I<offset>B<, off64_t >I<nbytes>B<);>\n"
+#: build/C/man2/s390_pci_mmio_write.2:100
+msgid "These system calls are available since Linux 3.19."
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:206
+#: build/C/man2/s390_pci_mmio_write.2:103
msgid ""
-"The behavior of this system call is otherwise exactly the same as "
-"B<sync_file_range>()."
+"This Linux-specific system call is available only on the s390 architecture. "
+"The required PCI support is available beginning with System z EC12."
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:217
+#: build/C/man2/s390_pci_mmio_write.2:107
msgid ""
-"A system call with this signature first appeared on the ARM architecture in "
-"Linux 2.6.20, with the name B<arm_sync_file_range>(). It was renamed in "
-"Linux 2.6.22, when the analogous system call was added for PowerPC. On "
-"architectures where glibc support is provided, glibc transparently wraps "
-"B<sync_file_range2>() under the name B<sync_file_range>()."
+"Glibc does not provide a wrapper for this system call, use B<syscall>(2) to "
+"call it."
msgstr ""
#. type: Plain text
-#: build/C/man2/sync_file_range.2:221
-msgid "B<fdatasync>(2), B<fsync>(2), B<msync>(2), B<sync>(2)"
+#: build/C/man2/s390_pci_mmio_write.2:109
+msgid "B<syscall>(2)"
msgstr ""
OSDN Git Service
