1 # SOME DESCRIPTIVE TITLE
2 # Copyright (C) YEAR Free Software Foundation, Inc.
3 # This file is distributed under the same license as the PACKAGE package.
4 # FIRST AUTHOR <EMAIL@ADDRESS>, YEAR.
9 "Project-Id-Version: PACKAGE VERSION\n"
10 "POT-Creation-Date: 2014-06-08 01:30+0900\n"
11 "PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
12 "Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
13 "Language-Team: LANGUAGE <LL@li.org>\n"
16 "Content-Type: text/plain; charset=UTF-8\n"
17 "Content-Transfer-Encoding: 8bit\n"
20 #: build/C/man3/bsd_signal.3:25
26 #: build/C/man3/bsd_signal.3:25
32 #: build/C/man3/bsd_signal.3:25 build/C/man2/eventfd.2:22 build/C/man2/getitimer.2:12 build/C/man3/gsignal.3:27 build/C/man2/kill.2:44 build/C/man2/killpg.2:42 build/C/man2/pause.2:30 build/C/man2/prctl.2:52 build/C/man3/profil.3:28 build/C/man3/psignal.3:30 build/C/man3/raise.3:29 build/C/man2/restart_syscall.2:33 build/C/man2/rt_sigqueueinfo.2:25 build/C/man2/s390_runtime_instr.2:25 build/C/man2/sgetmask.2:26 build/C/man2/sigaction.2:47 build/C/man2/sigaltstack.2:27 build/C/man7/sigevent.7:26 build/C/man3/siginterrupt.3:31 build/C/man2/signal.2:36 build/C/man7/signal.7:46 build/C/man2/signalfd.2:20 build/C/man3/sigpause.3:25 build/C/man2/sigpending.2:29 build/C/man2/sigprocmask.2:29 build/C/man3/sigqueue.3:28 build/C/man2/sigreturn.2:29 build/C/man3/sigset.3:26 build/C/man3/sigsetops.3:31 build/C/man2/sigsuspend.2:29 build/C/man3/sigvec.3:26 build/C/man3/sigwait.3:26 build/C/man2/sigwaitinfo.2:25 build/C/man3/sysv_signal.3:25 build/C/man2/timer_create.2:31 build/C/man2/timer_delete.2:26 build/C/man2/timer_getoverrun.2:26 build/C/man2/timer_settime.2:26 build/C/man2/timerfd_create.2:21 build/C/man2/tkill.2:29 build/C/man2/wait.2:49 build/C/man2/wait4.2:33
34 msgid "Linux Programmer's Manual"
38 #: build/C/man3/bsd_signal.3:26 build/C/man2/eventfd.2:23 build/C/man2/getitimer.2:13 build/C/man3/gsignal.3:28 build/C/man2/kill.2:45 build/C/man2/killpg.2:43 build/C/man2/pause.2:31 build/C/man2/prctl.2:53 build/C/man3/profil.3:29 build/C/man3/psignal.3:31 build/C/man3/raise.3:30 build/C/man2/restart_syscall.2:34 build/C/man2/rt_sigqueueinfo.2:26 build/C/man2/s390_runtime_instr.2:26 build/C/man2/sgetmask.2:27 build/C/man2/sigaction.2:48 build/C/man2/sigaltstack.2:28 build/C/man7/sigevent.7:27 build/C/man3/siginterrupt.3:32 build/C/man2/signal.2:37 build/C/man7/signal.7:47 build/C/man2/signalfd.2:21 build/C/man3/sigpause.3:26 build/C/man2/sigpending.2:30 build/C/man2/sigprocmask.2:30 build/C/man3/sigqueue.3:29 build/C/man2/sigreturn.2:30 build/C/man3/sigset.3:27 build/C/man3/sigsetops.3:32 build/C/man2/sigsuspend.2:30 build/C/man3/sigvec.3:27 build/C/man3/sigwait.3:27 build/C/man2/sigwaitinfo.2:26 build/C/man3/sysv_signal.3:26 build/C/man2/timer_create.2:32 build/C/man2/timer_delete.2:27 build/C/man2/timer_getoverrun.2:27 build/C/man2/timer_settime.2:27 build/C/man2/timerfd_create.2:22 build/C/man2/tkill.2:30 build/C/man2/wait.2:50 build/C/man2/wait4.2:34
44 #: build/C/man3/bsd_signal.3:28
45 msgid "bsd_signal - signal handling with BSD semantics"
49 #: build/C/man3/bsd_signal.3:28 build/C/man2/eventfd.2:25 build/C/man2/getitimer.2:15 build/C/man3/gsignal.3:30 build/C/man2/kill.2:47 build/C/man2/killpg.2:45 build/C/man2/pause.2:33 build/C/man2/prctl.2:55 build/C/man3/profil.3:31 build/C/man3/psignal.3:33 build/C/man3/raise.3:32 build/C/man2/restart_syscall.2:36 build/C/man2/rt_sigqueueinfo.2:28 build/C/man2/s390_runtime_instr.2:28 build/C/man2/sgetmask.2:29 build/C/man2/sigaction.2:50 build/C/man2/sigaltstack.2:30 build/C/man7/sigevent.7:29 build/C/man3/siginterrupt.3:34 build/C/man2/signal.2:39 build/C/man2/signalfd.2:23 build/C/man3/sigpause.3:28 build/C/man2/sigpending.2:32 build/C/man2/sigprocmask.2:32 build/C/man3/sigqueue.3:31 build/C/man2/sigreturn.2:32 build/C/man3/sigset.3:29 build/C/man3/sigsetops.3:35 build/C/man2/sigsuspend.2:32 build/C/man3/sigvec.3:29 build/C/man3/sigwait.3:29 build/C/man2/sigwaitinfo.2:28 build/C/man3/sysv_signal.3:28 build/C/man2/timer_create.2:34 build/C/man2/timer_delete.2:29 build/C/man2/timer_getoverrun.2:29 build/C/man2/timer_settime.2:30 build/C/man2/timerfd_create.2:25 build/C/man2/tkill.2:32 build/C/man2/wait.2:52 build/C/man2/wait4.2:36
55 #: build/C/man3/bsd_signal.3:30
56 msgid "B<#define _XOPEN_SOURCE> /* See feature_test_macros(7) */"
60 #: build/C/man3/bsd_signal.3:32 build/C/man2/killpg.2:47 build/C/man2/sigaltstack.2:32 build/C/man2/signal.2:41 build/C/man2/sigpending.2:34 build/C/man2/sigprocmask.2:34 build/C/man3/sigqueue.3:33 build/C/man3/sigset.3:31 build/C/man3/sigsetops.3:37 build/C/man2/sigsuspend.2:34 build/C/man3/sigvec.3:31 build/C/man3/sysv_signal.3:32
61 msgid "B<#include E<lt>signal.hE<gt>>"
65 #: build/C/man3/bsd_signal.3:34 build/C/man2/signal.2:43 build/C/man3/sigset.3:33 build/C/man3/sysv_signal.3:34
66 msgid "B<typedef void (*sighandler_t)(int);>"
70 #: build/C/man3/bsd_signal.3:36
71 msgid "B<sighandler_t bsd_signal(int >I<signum>B<, sighandler_t >I<handler>B<);>"
75 #: build/C/man3/bsd_signal.3:36 build/C/man2/eventfd.2:29 build/C/man2/getitimer.2:24 build/C/man3/gsignal.3:49 build/C/man2/kill.2:65 build/C/man2/killpg.2:60 build/C/man2/pause.2:37 build/C/man2/prctl.2:62 build/C/man3/profil.3:46 build/C/man3/psignal.3:56 build/C/man3/raise.3:38 build/C/man2/restart_syscall.2:41 build/C/man2/rt_sigqueueinfo.2:38 build/C/man2/s390_runtime_instr.2:34 build/C/man2/sgetmask.2:36 build/C/man2/sigaction.2:70 build/C/man2/sigaltstack.2:51 build/C/man7/sigevent.7:52 build/C/man3/siginterrupt.3:55 build/C/man2/signal.2:45 build/C/man7/signal.7:49 build/C/man2/signalfd.2:27 build/C/man3/sigpause.3:36 build/C/man2/sigpending.2:46 build/C/man2/sigprocmask.2:47 build/C/man3/sigqueue.3:43 build/C/man2/sigreturn.2:34 build/C/man3/sigset.3:58 build/C/man3/sigsetops.3:63 build/C/man2/sigsuspend.2:46 build/C/man3/sigvec.3:49 build/C/man3/sigwait.3:45 build/C/man2/sigwaitinfo.2:46 build/C/man3/sysv_signal.3:36 build/C/man2/timer_create.2:52 build/C/man2/timer_delete.2:45 build/C/man2/timer_getoverrun.2:45 build/C/man2/timer_settime.2:50 build/C/man2/timerfd_create.2:37 build/C/man2/tkill.2:41 build/C/man2/wait.2:83 build/C/man2/wait4.2:67
81 #: build/C/man3/bsd_signal.3:41
83 "The B<bsd_signal>() function takes the same arguments, and performs the "
84 "same task, as B<signal>(2)."
88 #: build/C/man3/bsd_signal.3:54
90 "The difference between the two is that B<bsd_signal>() is guaranteed to "
91 "provide reliable signal semantics, that is: a) the disposition of the signal "
92 "is not reset to the default when the handler is invoked; b) delivery of "
93 "further instances of the signal is blocked while the signal handler is "
94 "executing; and c) if the handler interrupts a blocking system call, then the "
95 "system call is automatically restarted. A portable application cannot rely "
96 "on B<signal>(2) to provide these guarantees."
100 #: build/C/man3/bsd_signal.3:54 build/C/man2/eventfd.2:222 build/C/man2/getitimer.2:122 build/C/man2/kill.2:100 build/C/man2/killpg.2:89 build/C/man2/pause.2:42 build/C/man2/prctl.2:802 build/C/man3/profil.3:68 build/C/man3/psignal.3:89 build/C/man3/raise.3:61 build/C/man2/restart_syscall.2:84 build/C/man2/rt_sigqueueinfo.2:129 build/C/man2/s390_runtime_instr.2:54 build/C/man2/sgetmask.2:59 build/C/man2/sigaction.2:660 build/C/man2/sigaltstack.2:133 build/C/man3/siginterrupt.3:73 build/C/man2/signal.2:97 build/C/man2/signalfd.2:251 build/C/man3/sigpause.3:48 build/C/man2/sigpending.2:53 build/C/man2/sigprocmask.2:93 build/C/man3/sigqueue.3:83 build/C/man2/sigreturn.2:53 build/C/man3/sigset.3:129 build/C/man3/sigsetops.3:107 build/C/man2/sigsuspend.2:70 build/C/man3/sigvec.3:199 build/C/man3/sigwait.3:69 build/C/man2/sigwaitinfo.2:105 build/C/man3/sysv_signal.3:51 build/C/man2/timer_create.2:167 build/C/man2/timer_delete.2:53 build/C/man2/timer_getoverrun.2:82 build/C/man2/timer_settime.2:173 build/C/man2/timerfd_create.2:287 build/C/man2/tkill.2:95 build/C/man2/wait.2:355 build/C/man2/wait4.2:132
106 #: build/C/man3/bsd_signal.3:60
108 "The B<bsd_signal>() function returns the previous value of the signal "
109 "handler, or B<SIG_ERR> on error."
113 #: build/C/man3/bsd_signal.3:60 build/C/man2/eventfd.2:229 build/C/man2/getitimer.2:127 build/C/man2/kill.2:105 build/C/man2/killpg.2:94 build/C/man2/pause.2:53 build/C/man2/prctl.2:822 build/C/man2/restart_syscall.2:88 build/C/man2/rt_sigqueueinfo.2:134 build/C/man2/s390_runtime_instr.2:65 build/C/man2/sgetmask.2:64 build/C/man2/sigaction.2:665 build/C/man2/sigaltstack.2:137 build/C/man3/siginterrupt.3:83 build/C/man2/signal.2:105 build/C/man2/signalfd.2:265 build/C/man2/sigpending.2:59 build/C/man2/sigprocmask.2:99 build/C/man3/sigqueue.3:91 build/C/man3/sigset.3:154 build/C/man3/sigsetops.3:126 build/C/man2/sigsuspend.2:76 build/C/man3/sigvec.3:216 build/C/man3/sigwait.3:74 build/C/man2/sigwaitinfo.2:114 build/C/man3/sysv_signal.3:57 build/C/man2/timer_create.2:175 build/C/man2/timer_delete.2:60 build/C/man2/timer_getoverrun.2:90 build/C/man2/timer_settime.2:182 build/C/man2/timerfd_create.2:302 build/C/man2/tkill.2:99 build/C/man2/wait.2:384 build/C/man2/wait4.2:135
119 #: build/C/man3/bsd_signal.3:63 build/C/man3/sysv_signal.3:60
120 msgid "As for B<signal>(2)."
124 #: build/C/man3/bsd_signal.3:63 build/C/man3/raise.3:64 build/C/man3/sigpause.3:56 build/C/man3/sigqueue.3:114 build/C/man3/sigsetops.3:131 build/C/man3/sigvec.3:221 build/C/man3/sigwait.3:80 build/C/man3/sysv_signal.3:60
130 #: build/C/man3/bsd_signal.3:64 build/C/man3/raise.3:65 build/C/man3/sigpause.3:57 build/C/man3/sigqueue.3:115 build/C/man3/sigsetops.3:132 build/C/man3/sigvec.3:222 build/C/man3/sigwait.3:81 build/C/man3/sysv_signal.3:61
132 msgid "Multithreading (see pthreads(7))"
136 #: build/C/man3/bsd_signal.3:68
137 msgid "The B<bsd_signal>() function is thread-safe."
141 #: build/C/man3/bsd_signal.3:68 build/C/man2/eventfd.2:266 build/C/man2/getitimer.2:148 build/C/man3/gsignal.3:95 build/C/man2/kill.2:121 build/C/man2/killpg.2:111 build/C/man2/pause.2:57 build/C/man2/prctl.2:1068 build/C/man3/profil.3:70 build/C/man3/psignal.3:99 build/C/man3/raise.3:69 build/C/man2/restart_syscall.2:96 build/C/man2/rt_sigqueueinfo.2:176 build/C/man2/s390_runtime_instr.2:81 build/C/man2/sgetmask.2:66 build/C/man2/sigaction.2:677 build/C/man2/sigaltstack.2:158 build/C/man7/sigevent.7:130 build/C/man3/siginterrupt.3:87 build/C/man2/signal.2:110 build/C/man7/signal.7:838 build/C/man2/signalfd.2:307 build/C/man3/sigpause.3:61 build/C/man2/sigpending.2:64 build/C/man2/sigprocmask.2:112 build/C/man3/sigqueue.3:119 build/C/man2/sigreturn.2:60 build/C/man3/sigset.3:173 build/C/man3/sigsetops.3:144 build/C/man2/sigsuspend.2:84 build/C/man3/sigvec.3:234 build/C/man3/sigwait.3:85 build/C/man2/sigwaitinfo.2:133 build/C/man3/sysv_signal.3:65 build/C/man2/timer_create.2:193 build/C/man2/timer_delete.2:67 build/C/man2/timer_getoverrun.2:97 build/C/man2/timer_settime.2:207 build/C/man2/timerfd_create.2:371 build/C/man2/tkill.2:116 build/C/man2/wait.2:422 build/C/man2/wait4.2:138
143 msgid "CONFORMING TO"
147 #: build/C/man3/bsd_signal.3:75
149 "4.2BSD, POSIX.1-2001. POSIX.1-2008 removes the specification of "
150 "B<bsd_signal>(), recommending the use of B<sigaction>(2) instead."
154 #: build/C/man3/bsd_signal.3:75 build/C/man2/eventfd.2:271 build/C/man2/getitimer.2:158 build/C/man2/kill.2:123 build/C/man2/killpg.2:115 build/C/man3/raise.3:71 build/C/man2/restart_syscall.2:98 build/C/man2/rt_sigqueueinfo.2:178 build/C/man2/s390_runtime_instr.2:84 build/C/man2/sgetmask.2:68 build/C/man2/sigaction.2:680 build/C/man2/sigaltstack.2:160 build/C/man2/signal.2:112 build/C/man2/signalfd.2:312 build/C/man3/sigpause.3:65 build/C/man2/sigpending.2:66 build/C/man2/sigprocmask.2:114 build/C/man3/sigqueue.3:121 build/C/man2/sigreturn.2:64 build/C/man3/sigset.3:190 build/C/man3/sigsetops.3:146 build/C/man2/sigsuspend.2:86 build/C/man3/sigvec.3:240 build/C/man3/sigwait.3:87 build/C/man2/sigwaitinfo.2:135 build/C/man3/sysv_signal.3:67 build/C/man2/timer_create.2:195 build/C/man2/timer_getoverrun.2:99 build/C/man2/tkill.2:122 build/C/man2/wait.2:424 build/C/man2/wait4.2:147
160 #: build/C/man3/bsd_signal.3:81
161 msgid "Use of B<bsd_signal>() should be avoided; use B<sigaction>(2) instead."
165 #: build/C/man3/bsd_signal.3:92
167 "On modern Linux systems, B<bsd_signal>() and B<signal>(2) are equivalent. "
168 "But on older systems, B<signal>(2) provided unreliable signal semantics; "
169 "see B<signal>(2) for details."
173 #: build/C/man3/bsd_signal.3:99 build/C/man3/sysv_signal.3:92
175 "The use of I<sighandler_t> is a GNU extension; this type is defined only if "
176 "the B<_GNU_SOURCE> feature test macro is defined."
180 #: build/C/man3/bsd_signal.3:99 build/C/man2/eventfd.2:417 build/C/man2/getitimer.2:239 build/C/man3/gsignal.3:103 build/C/man2/kill.2:171 build/C/man2/killpg.2:134 build/C/man2/pause.2:59 build/C/man2/prctl.2:1082 build/C/man3/profil.3:81 build/C/man3/psignal.3:113 build/C/man3/raise.3:82 build/C/man2/restart_syscall.2:123 build/C/man2/rt_sigqueueinfo.2:188 build/C/man2/s390_runtime_instr.2:88 build/C/man2/sgetmask.2:82 build/C/man2/sigaction.2:793 build/C/man2/sigaltstack.2:234 build/C/man7/sigevent.7:132 build/C/man3/siginterrupt.3:96 build/C/man2/signal.2:278 build/C/man7/signal.7:850 build/C/man2/signalfd.2:433 build/C/man3/sigpause.3:111 build/C/man2/sigpending.2:91 build/C/man2/sigprocmask.2:144 build/C/man3/sigqueue.3:154 build/C/man2/sigreturn.2:74 build/C/man3/sigset.3:266 build/C/man3/sigsetops.3:185 build/C/man2/sigsuspend.2:108 build/C/man3/sigvec.3:265 build/C/man3/sigwait.3:94 build/C/man2/sigwaitinfo.2:187 build/C/man3/sysv_signal.3:92 build/C/man2/timer_create.2:407 build/C/man2/timer_delete.2:69 build/C/man2/timer_getoverrun.2:131 build/C/man2/timer_settime.2:212 build/C/man2/timerfd_create.2:541 build/C/man2/tkill.2:131 build/C/man2/wait.2:634 build/C/man2/wait4.2:165
186 #: build/C/man3/bsd_signal.3:104
187 msgid "B<sigaction>(2), B<signal>(2), B<sysv_signal>(3), B<signal>(7)"
191 #: build/C/man3/bsd_signal.3:104 build/C/man2/eventfd.2:428 build/C/man2/getitimer.2:246 build/C/man3/gsignal.3:107 build/C/man2/kill.2:181 build/C/man2/killpg.2:140 build/C/man2/pause.2:64 build/C/man2/prctl.2:1085 build/C/man3/profil.3:86 build/C/man3/psignal.3:118 build/C/man3/raise.3:89 build/C/man2/restart_syscall.2:131 build/C/man2/rt_sigqueueinfo.2:196 build/C/man2/s390_runtime_instr.2:91 build/C/man2/sgetmask.2:85 build/C/man2/sigaction.2:813 build/C/man2/sigaltstack.2:241 build/C/man7/sigevent.7:142 build/C/man3/siginterrupt.3:98 build/C/man2/signal.2:297 build/C/man7/signal.7:884 build/C/man2/signalfd.2:446 build/C/man3/sigpause.3:119 build/C/man2/sigpending.2:99 build/C/man2/sigprocmask.2:155 build/C/man3/sigqueue.3:162 build/C/man2/sigreturn.2:80 build/C/man3/sigset.3:276 build/C/man3/sigsetops.3:190 build/C/man2/sigsuspend.2:118 build/C/man3/sigvec.3:275 build/C/man3/sigwait.3:102 build/C/man2/sigwaitinfo.2:199 build/C/man3/sysv_signal.3:97 build/C/man2/timer_create.2:422 build/C/man2/timer_delete.2:75 build/C/man2/timer_getoverrun.2:141 build/C/man2/timer_settime.2:216 build/C/man2/timerfd_create.2:553 build/C/man2/tkill.2:136 build/C/man2/wait.2:646 build/C/man2/wait4.2:172
197 #: build/C/man3/bsd_signal.3:112 build/C/man2/eventfd.2:436 build/C/man2/getitimer.2:254 build/C/man3/gsignal.3:115 build/C/man2/kill.2:189 build/C/man2/killpg.2:148 build/C/man2/pause.2:72 build/C/man2/prctl.2:1093 build/C/man3/profil.3:94 build/C/man3/psignal.3:126 build/C/man3/raise.3:97 build/C/man2/restart_syscall.2:139 build/C/man2/rt_sigqueueinfo.2:204 build/C/man2/s390_runtime_instr.2:99 build/C/man2/sgetmask.2:93 build/C/man2/sigaction.2:821 build/C/man2/sigaltstack.2:249 build/C/man7/sigevent.7:150 build/C/man3/siginterrupt.3:106 build/C/man2/signal.2:305 build/C/man7/signal.7:892 build/C/man2/signalfd.2:454 build/C/man3/sigpause.3:127 build/C/man2/sigpending.2:107 build/C/man2/sigprocmask.2:163 build/C/man3/sigqueue.3:170 build/C/man2/sigreturn.2:88 build/C/man3/sigset.3:284 build/C/man3/sigsetops.3:198 build/C/man2/sigsuspend.2:126 build/C/man3/sigvec.3:283 build/C/man3/sigwait.3:110 build/C/man2/sigwaitinfo.2:207 build/C/man3/sysv_signal.3:105 build/C/man2/timer_create.2:430 build/C/man2/timer_delete.2:83 build/C/man2/timer_getoverrun.2:149 build/C/man2/timer_settime.2:224 build/C/man2/timerfd_create.2:561 build/C/man2/tkill.2:144 build/C/man2/wait.2:654 build/C/man2/wait4.2:180
199 "This page is part of release 3.68 of the Linux I<man-pages> project. A "
200 "description of the project, information about reporting bugs, and the latest "
201 "version of this page, can be found at "
202 "\\%http://www.kernel.org/doc/man-pages/."
206 #: build/C/man2/eventfd.2:22
212 #: build/C/man2/eventfd.2:22
218 #: build/C/man2/eventfd.2:22 build/C/man2/getitimer.2:12 build/C/man2/kill.2:44 build/C/man2/killpg.2:42 build/C/man2/pause.2:30 build/C/man2/prctl.2:52 build/C/man3/profil.3:28 build/C/man2/restart_syscall.2:33 build/C/man2/rt_sigqueueinfo.2:25 build/C/man2/sgetmask.2:26 build/C/man2/sigaction.2:47 build/C/man2/sigaltstack.2:27 build/C/man2/signal.2:36 build/C/man7/signal.7:46 build/C/man2/signalfd.2:20 build/C/man3/sigpause.3:25 build/C/man2/sigpending.2:29 build/C/man2/sigprocmask.2:29 build/C/man3/sigqueue.3:28 build/C/man2/sigreturn.2:29 build/C/man3/sigset.3:26 build/C/man3/sigsetops.3:31 build/C/man2/sigsuspend.2:29 build/C/man3/sigvec.3:26 build/C/man3/sigwait.3:26 build/C/man2/sigwaitinfo.2:25 build/C/man2/timer_create.2:31 build/C/man2/timer_delete.2:26 build/C/man2/timer_getoverrun.2:26 build/C/man2/timer_settime.2:26 build/C/man2/timerfd_create.2:21 build/C/man2/tkill.2:29 build/C/man2/wait.2:49 build/C/man2/wait4.2:33
224 #: build/C/man2/eventfd.2:25
225 msgid "eventfd - create a file descriptor for event notification"
229 #: build/C/man2/eventfd.2:27
230 msgid "B<#include E<lt>sys/eventfd.hE<gt>>"
234 #: build/C/man2/eventfd.2:29
235 msgid "B<int eventfd(unsigned int >I<initval>B<, int >I<flags>B<);>"
239 #: build/C/man2/eventfd.2:39
241 "B<eventfd>() creates an \"eventfd object\" that can be used as an event "
242 "wait/notify mechanism by user-space applications, and by the kernel to "
243 "notify user-space applications of events. The object contains an unsigned "
244 "64-bit integer (I<uint64_t>) counter that is maintained by the kernel. "
245 "This counter is initialized with the value specified in the argument "
250 #: build/C/man2/eventfd.2:44
252 "The following values may be bitwise ORed in I<flags> to change the behaviour "
257 #: build/C/man2/eventfd.2:44
259 msgid "B<EFD_CLOEXEC> (since Linux 2.6.27)"
263 #: build/C/man2/eventfd.2:54 build/C/man2/signalfd.2:95 build/C/man2/timerfd_create.2:103
265 "Set the close-on-exec (B<FD_CLOEXEC>) flag on the new file descriptor. See "
266 "the description of the B<O_CLOEXEC> flag in B<open>(2) for reasons why this "
271 #: build/C/man2/eventfd.2:54
273 msgid "B<EFD_NONBLOCK> (since Linux 2.6.27)"
277 #: build/C/man2/eventfd.2:62 build/C/man2/signalfd.2:85 build/C/man2/timerfd_create.2:93
279 "Set the B<O_NONBLOCK> file status flag on the new open file description. "
280 "Using this flag saves extra calls to B<fcntl>(2) to achieve the same "
285 #: build/C/man2/eventfd.2:62
287 msgid "B<EFD_SEMAPHORE> (since Linux 2.6.30)"
291 #: build/C/man2/eventfd.2:66
293 "Provide semaphore-like semantics for reads from the new file descriptor. "
298 #: build/C/man2/eventfd.2:70 build/C/man2/signalfd.2:99
300 "In Linux up to version 2.6.26, the I<flags> argument is unused, and must be "
305 #: build/C/man2/eventfd.2:76
307 "As its return value, B<eventfd>() returns a new file descriptor that can be "
308 "used to refer to the eventfd object. The following operations can be "
309 "performed on the file descriptor:"
313 #: build/C/man2/eventfd.2:76 build/C/man2/signalfd.2:102 build/C/man2/timerfd_create.2:211
319 #: build/C/man2/eventfd.2:86
321 "Each successful B<read>(2) returns an 8-byte integer. A B<read>(2) will "
322 "fail with the error B<EINVAL> if the size of the supplied buffer is less "
327 #: build/C/man2/eventfd.2:91
329 "The value returned by B<read>(2) is in host byte order\\(emthat is, the "
330 "native byte order for integers on the host machine."
334 #: build/C/man2/eventfd.2:98
336 "The semantics of B<read>(2) depend on whether the eventfd counter currently "
337 "has a nonzero value and whether the B<EFD_SEMAPHORE> flag was specified when "
338 "creating the eventfd file descriptor:"
342 #: build/C/man2/eventfd.2:99 build/C/man2/eventfd.2:106 build/C/man2/eventfd.2:113 build/C/man2/eventfd.2:158 build/C/man2/eventfd.2:168 build/C/man2/eventfd.2:178 build/C/man2/prctl.2:865 build/C/man2/prctl.2:870 build/C/man2/prctl.2:875 build/C/man2/prctl.2:885 build/C/man3/psignal.3:105 build/C/man3/psignal.3:109 build/C/man2/sigaction.2:298 build/C/man2/sigaction.2:313 build/C/man2/sigaction.2:329 build/C/man2/sigaction.2:344 build/C/man2/sigaction.2:391 build/C/man2/sigaction.2:427 build/C/man2/signal.2:68 build/C/man2/signal.2:73 build/C/man2/signal.2:80 build/C/man2/signal.2:224 build/C/man2/signal.2:228 build/C/man2/signal.2:267 build/C/man7/signal.7:149 build/C/man7/signal.7:157 build/C/man7/signal.7:615 build/C/man7/signal.7:617 build/C/man7/signal.7:638 build/C/man7/signal.7:653 build/C/man7/signal.7:657 build/C/man7/signal.7:664 build/C/man7/signal.7:680 build/C/man7/signal.7:686 build/C/man7/signal.7:693 build/C/man7/signal.7:698 build/C/man7/signal.7:717 build/C/man7/signal.7:736 build/C/man7/signal.7:743 build/C/man7/signal.7:752 build/C/man7/signal.7:760 build/C/man7/signal.7:766 build/C/man7/signal.7:771 build/C/man7/signal.7:791 build/C/man7/signal.7:810 build/C/man7/signal.7:813 build/C/man7/signal.7:816 build/C/man7/signal.7:819 build/C/man7/signal.7:824 build/C/man7/signal.7:830 build/C/man7/signal.7:834 build/C/man3/sigwait.3:62 build/C/man3/sigwait.3:67 build/C/man2/timer_create.2:216 build/C/man2/timer_create.2:219 build/C/man2/timer_create.2:222 build/C/man2/timer_create.2:226 build/C/man2/timer_create.2:229 build/C/man2/timer_create.2:235 build/C/man2/timer_create.2:239
348 #: build/C/man2/eventfd.2:106
350 "If B<EFD_SEMAPHORE> was not specified and the eventfd counter has a nonzero "
351 "value, then a B<read>(2) returns 8 bytes containing that value, and the "
352 "counter's value is reset to zero."
356 #: build/C/man2/eventfd.2:113
358 "If B<EFD_SEMAPHORE> was specified and the eventfd counter has a nonzero "
359 "value, then a B<read>(2) returns 8 bytes containing the value 1, and the "
360 "counter's value is decremented by 1."
364 #: build/C/man2/eventfd.2:123
366 "If the eventfd counter is zero at the time of the call to B<read>(2), then "
367 "the call either blocks until the counter becomes nonzero (at which time, the "
368 "B<read>(2) proceeds as described above) or fails with the error B<EAGAIN> "
369 "if the file descriptor has been made nonblocking."
373 #: build/C/man2/eventfd.2:124
379 #: build/C/man2/eventfd.2:141
381 "A B<write>(2) call adds the 8-byte integer value supplied in its buffer to "
382 "the counter. The maximum value that may be stored in the counter is the "
383 "largest unsigned 64-bit value minus 1 (i.e., 0xfffffffffffffffe). If the "
384 "addition would cause the counter's value to exceed the maximum, then the "
385 "B<write>(2) either blocks until a B<read>(2) is performed on the file "
386 "descriptor, or fails with the error B<EAGAIN> if the file descriptor has "
387 "been made nonblocking."
391 #: build/C/man2/eventfd.2:148
393 "A B<write>(2) will fail with the error B<EINVAL> if the size of the "
394 "supplied buffer is less than 8 bytes, or if an attempt is made to write the "
395 "value 0xffffffffffffffff."
399 #: build/C/man2/eventfd.2:148 build/C/man2/signalfd.2:140 build/C/man2/timerfd_create.2:244
401 msgid "B<poll>(2), B<select>(2) (and similar)"
405 #: build/C/man2/eventfd.2:157
407 "The returned file descriptor supports B<poll>(2) (and analogously "
408 "B<epoll>(7)) and B<select>(2), as follows:"
412 #: build/C/man2/eventfd.2:168
414 "The file descriptor is readable (the B<select>(2) I<readfds> argument; the "
415 "B<poll>(2) B<POLLIN> flag) if the counter has a value greater than 0."
419 #: build/C/man2/eventfd.2:178
421 "The file descriptor is writable (the B<select>(2) I<writefds> argument; the "
422 "B<poll>(2) B<POLLOUT> flag) if it is possible to write a value of at least "
423 "\"1\" without blocking."
427 #: build/C/man2/eventfd.2:198
429 "If an overflow of the counter value was detected, then B<select>(2) "
430 "indicates the file descriptor as being both readable and writable, and "
431 "B<poll>(2) returns a B<POLLERR> event. As noted above, B<write>(2) can "
432 "never overflow the counter. However an overflow can occur if 2^64 eventfd "
433 "\"signal posts\" were performed by the KAIO subsystem (theoretically "
434 "possible, but practically unlikely). If an overflow has occurred, then "
435 "B<read>(2) will return that maximum I<uint64_t> value (i.e., "
436 "0xffffffffffffffff)."
440 #: build/C/man2/eventfd.2:205
442 "The eventfd file descriptor also supports the other file-descriptor "
443 "multiplexing APIs: B<pselect>(2) and B<ppoll>(2)."
447 #: build/C/man2/eventfd.2:205 build/C/man2/signalfd.2:160 build/C/man2/timerfd_create.2:262
453 #: build/C/man2/eventfd.2:210
455 "When the file descriptor is no longer required it should be closed. When "
456 "all file descriptors associated with the same eventfd object have been "
457 "closed, the resources for object are freed by the kernel."
461 #: build/C/man2/eventfd.2:222
463 "A copy of the file descriptor created by B<eventfd>() is inherited by the "
464 "child produced by B<fork>(2). The duplicate file descriptor is associated "
465 "with the same eventfd object. File descriptors created by B<eventfd>() are "
466 "preserved across B<execve>(2), unless the close-on-exec flag has been set."
470 #: build/C/man2/eventfd.2:229
472 "On success, B<eventfd>() returns a new eventfd file descriptor. On error, "
473 "-1 is returned and I<errno> is set to indicate the error."
477 #: build/C/man2/eventfd.2:230 build/C/man2/getitimer.2:135 build/C/man2/kill.2:106 build/C/man2/killpg.2:95 build/C/man2/prctl.2:827 build/C/man2/prctl.2:832 build/C/man2/prctl.2:844 build/C/man2/prctl.2:849 build/C/man2/prctl.2:858 build/C/man2/prctl.2:898 build/C/man2/prctl.2:908 build/C/man2/prctl.2:916 build/C/man2/prctl.2:927 build/C/man2/prctl.2:936 build/C/man2/prctl.2:950 build/C/man2/prctl.2:962 build/C/man2/prctl.2:973 build/C/man2/rt_sigqueueinfo.2:141 build/C/man2/s390_runtime_instr.2:66 build/C/man2/sigaction.2:670 build/C/man2/sigaltstack.2:142 build/C/man3/siginterrupt.3:84 build/C/man2/signal.2:106 build/C/man2/signalfd.2:271 build/C/man2/signalfd.2:279 build/C/man2/sigprocmask.2:107 build/C/man3/sigqueue.3:98 build/C/man3/sigsetops.3:127 build/C/man3/sigwait.3:75 build/C/man2/sigwaitinfo.2:129 build/C/man2/timer_create.2:179 build/C/man2/timer_delete.2:61 build/C/man2/timer_getoverrun.2:91 build/C/man2/timer_settime.2:191 build/C/man2/timer_settime.2:199 build/C/man2/timerfd_create.2:305 build/C/man2/timerfd_create.2:313 build/C/man2/timerfd_create.2:349 build/C/man2/timerfd_create.2:356 build/C/man2/timerfd_create.2:362 build/C/man2/tkill.2:100 build/C/man2/wait.2:417
483 #: build/C/man2/eventfd.2:234
484 msgid "An unsupported value was specified in I<flags>."
488 #: build/C/man2/eventfd.2:234 build/C/man2/signalfd.2:286 build/C/man2/timerfd_create.2:320
494 #: build/C/man2/eventfd.2:237
495 msgid "The per-process limit on open file descriptors has been reached."
499 #: build/C/man2/eventfd.2:237 build/C/man2/signalfd.2:289 build/C/man2/timerfd_create.2:323
505 #: build/C/man2/eventfd.2:241 build/C/man2/signalfd.2:293 build/C/man2/timerfd_create.2:327
506 msgid "The system-wide limit on the total number of open files has been reached."
510 #: build/C/man2/eventfd.2:241 build/C/man2/signalfd.2:293 build/C/man2/timerfd_create.2:327
516 #: build/C/man2/eventfd.2:249 build/C/man2/signalfd.2:296 build/C/man2/timerfd_create.2:330
517 msgid "Could not mount (internal) anonymous inode device."
521 #: build/C/man2/eventfd.2:249 build/C/man2/s390_runtime_instr.2:73 build/C/man2/sigaltstack.2:147 build/C/man2/signalfd.2:296 build/C/man2/timer_create.2:187 build/C/man2/timerfd_create.2:330
527 #: build/C/man2/eventfd.2:253
528 msgid "There was insufficient memory to create a new eventfd file descriptor."
532 #: build/C/man2/eventfd.2:253 build/C/man2/prctl.2:1063 build/C/man3/psignal.3:95 build/C/man2/restart_syscall.2:92 build/C/man2/rt_sigqueueinfo.2:169 build/C/man2/s390_runtime_instr.2:79 build/C/man2/signalfd.2:299 build/C/man3/sigqueue.3:112 build/C/man2/timer_create.2:191 build/C/man2/timer_delete.2:65 build/C/man2/timer_getoverrun.2:95 build/C/man2/timer_settime.2:205 build/C/man2/timerfd_create.2:368 build/C/man2/tkill.2:111
537 #. eventfd() is in glibc 2.7, but reportedly does not build
539 #: build/C/man2/eventfd.2:266
541 "B<eventfd>() is available on Linux since kernel 2.6.22. Working support is "
542 "provided in glibc since version 2.8. The B<eventfd2>() system call (see "
543 "NOTES) is available on Linux since kernel 2.6.27. Since version 2.9, the "
544 "glibc B<eventfd>() wrapper will employ the B<eventfd2>() system call, if "
545 "it is supported by the kernel."
549 #: build/C/man2/eventfd.2:271
550 msgid "B<eventfd>() and B<eventfd2>() are Linux-specific."
554 #: build/C/man2/eventfd.2:279
556 "Applications can use an eventfd file descriptor instead of a pipe (see "
557 "B<pipe>(2)) in all cases where a pipe is used simply to signal events. The "
558 "kernel overhead of an eventfd file descriptor is much lower than that of a "
559 "pipe, and only one file descriptor is required (versus the two required for "
563 #. or eventually syslets/threadlets
565 #: build/C/man2/eventfd.2:285
567 "When used in the kernel, an eventfd file descriptor can provide a bridge "
568 "from kernel to user space, allowing, for example, functionalities like KAIO "
569 "(kernel AIO) to signal to a file descriptor that some operation is "
574 #: build/C/man2/eventfd.2:302
576 "A key point about an eventfd file descriptor is that it can be monitored "
577 "just like any other file descriptor using B<select>(2), B<poll>(2), or "
578 "B<epoll>(7). This means that an application can simultaneously monitor the "
579 "readiness of \"traditional\" files and the readiness of other kernel "
580 "mechanisms that support the eventfd interface. (Without the B<eventfd>() "
581 "interface, these mechanisms could not be multiplexed via B<select>(2), "
582 "B<poll>(2), or B<epoll>(7).)"
586 #: build/C/man2/eventfd.2:302 build/C/man2/signalfd.2:336
588 msgid "Underlying Linux system calls"
592 #: build/C/man2/eventfd.2:316
594 "There are two underlying Linux system calls: B<eventfd>() and the more "
595 "recent B<eventfd2>(). The former system call does not implement a I<flags> "
596 "argument. The latter system call implements the I<flags> values described "
597 "above. The glibc wrapper function will use B<eventfd2>() where it is "
602 #: build/C/man2/eventfd.2:316
604 msgid "Additional glibc features"
608 #: build/C/man2/eventfd.2:320
610 "The GNU C library defines an additional type, and two functions that attempt "
611 "to abstract some of the details of reading and writing on an eventfd file "
616 #: build/C/man2/eventfd.2:324
618 msgid "typedef uint64_t eventfd_t;\n"
622 #: build/C/man2/eventfd.2:327
625 "int eventfd_read(int fd, eventfd_t *value);\n"
626 "int eventfd_write(int fd, eventfd_t value);\n"
630 #: build/C/man2/eventfd.2:334
632 "The functions perform the read and write operations on an eventfd file "
633 "descriptor, returning 0 if the correct number of bytes was transferred, or "
638 #: build/C/man2/eventfd.2:334 build/C/man2/sigaction.2:790 build/C/man2/sigaltstack.2:217 build/C/man2/signalfd.2:360 build/C/man3/sigwait.3:91 build/C/man2/timer_create.2:261 build/C/man2/timer_getoverrun.2:128 build/C/man2/timer_settime.2:209 build/C/man2/timerfd_create.2:379 build/C/man2/wait.2:551
644 #: build/C/man2/eventfd.2:343
646 "The following program creates an eventfd file descriptor and then forks to "
647 "create a child process. While the parent briefly sleeps, the child writes "
648 "each of the integers supplied in the program's command-line arguments to the "
649 "eventfd file descriptor. When the parent has finished sleeping, it reads "
650 "from the eventfd file descriptor."
654 #: build/C/man2/eventfd.2:345
655 msgid "The following shell session shows a sample run of the program:"
659 #: build/C/man2/eventfd.2:357
662 "$B< ./a.out 1 2 4 7 14>\n"
663 "Child writing 1 to efd\n"
664 "Child writing 2 to efd\n"
665 "Child writing 4 to efd\n"
666 "Child writing 7 to efd\n"
667 "Child writing 14 to efd\n"
668 "Child completed write loop\n"
669 "Parent about to read\n"
670 "Parent read 28 (0x1c) from efd\n"
674 #: build/C/man2/eventfd.2:359 build/C/man2/signalfd.2:383 build/C/man2/timer_create.2:292 build/C/man2/timerfd_create.2:407 build/C/man2/wait.2:586
676 msgid "Program source"
680 #: build/C/man2/eventfd.2:367
683 "#include E<lt>sys/eventfd.hE<gt>\n"
684 "#include E<lt>unistd.hE<gt>\n"
685 "#include E<lt>stdlib.hE<gt>\n"
686 "#include E<lt>stdio.hE<gt>\n"
687 "#include E<lt>stdint.hE<gt> /* Definition of uint64_t */\n"
691 #: build/C/man2/eventfd.2:370 build/C/man2/signalfd.2:394
694 "#define handle_error(msg) \\e\n"
695 " do { perror(msg); exit(EXIT_FAILURE); } while (0)\n"
699 #: build/C/man2/eventfd.2:377
703 "main(int argc, char *argv[])\n"
711 #: build/C/man2/eventfd.2:382
714 " if (argc E<lt> 2) {\n"
715 " fprintf(stderr, \"Usage: %s E<lt>numE<gt>...\\en\", argv[0]);\n"
716 " exit(EXIT_FAILURE);\n"
721 #: build/C/man2/eventfd.2:386
724 " efd = eventfd(0, 0);\n"
726 " handle_error(\"eventfd\");\n"
730 #: build/C/man2/eventfd.2:398
733 " switch (fork()) {\n"
735 " for (j = 1; j E<lt> argc; j++) {\n"
736 " printf(\"Child writing %s to efd\\en\", argv[j]);\n"
737 " u = strtoull(argv[j], NULL, 0);\n"
738 " /* strtoull() allows various bases */\n"
739 " s = write(efd, &u, sizeof(uint64_t));\n"
740 " if (s != sizeof(uint64_t))\n"
741 " handle_error(\"write\");\n"
743 " printf(\"Child completed write loop\\en\");\n"
747 #: build/C/man2/eventfd.2:400
749 msgid " exit(EXIT_SUCCESS);\n"
753 #: build/C/man2/eventfd.2:403
761 #: build/C/man2/eventfd.2:411
764 " printf(\"Parent about to read\\en\");\n"
765 " s = read(efd, &u, sizeof(uint64_t));\n"
766 " if (s != sizeof(uint64_t))\n"
767 " handle_error(\"read\");\n"
768 " printf(\"Parent read %llu (0x%llx) from efd\\en\",\n"
769 " (unsigned long long) u, (unsigned long long) u);\n"
770 " exit(EXIT_SUCCESS);\n"
774 #: build/C/man2/eventfd.2:416
778 " handle_error(\"fork\");\n"
784 #: build/C/man2/eventfd.2:428
786 "B<futex>(2), B<pipe>(2), B<poll>(2), B<read>(2), B<select>(2), "
787 "B<signalfd>(2), B<timerfd_create>(2), B<write>(2), B<epoll>(7), "
792 #: build/C/man2/getitimer.2:12
798 #: build/C/man2/getitimer.2:12
804 #: build/C/man2/getitimer.2:15
805 msgid "getitimer, setitimer - get or set value of an interval timer"
809 #: build/C/man2/getitimer.2:18
811 msgid "B<#include E<lt>sys/time.hE<gt>>\n"
815 #: build/C/man2/getitimer.2:20
817 msgid "B<int getitimer(int >I<which>B<, struct itimerval *>I<curr_value>B<);>\n"
821 #: build/C/man2/getitimer.2:23
824 "B<int setitimer(int >I<which>B<, const struct itimerval *>I<new_value>B<,>\n"
825 "B< struct itimerval *>I<old_value>B<);>\n"
829 #: build/C/man2/getitimer.2:29
831 "The system provides each process with three interval timers, each "
832 "decrementing in a distinct time domain. When any timer expires, a signal is "
833 "sent to the process, and the timer (potentially) restarts."
837 #: build/C/man2/getitimer.2:29
839 msgid "B<ITIMER_REAL>"
843 #: build/C/man2/getitimer.2:34
844 msgid "decrements in real time, and delivers B<SIGALRM> upon expiration."
848 #: build/C/man2/getitimer.2:34
850 msgid "B<ITIMER_VIRTUAL>"
854 #: build/C/man2/getitimer.2:39
856 "decrements only when the process is executing, and delivers B<SIGVTALRM> "
861 #: build/C/man2/getitimer.2:39
863 msgid "B<ITIMER_PROF>"
867 #: build/C/man2/getitimer.2:49
869 "decrements both when the process executes and when the system is executing "
870 "on behalf of the process. Coupled with B<ITIMER_VIRTUAL>, this timer is "
871 "usually used to profile the time spent by the application in user and kernel "
872 "space. B<SIGPROF> is delivered upon expiration."
876 #: build/C/man2/getitimer.2:51
877 msgid "Timer values are defined by the following structures:"
881 #: build/C/man2/getitimer.2:59
884 "struct itimerval {\n"
885 " struct timeval it_interval; /* next value */\n"
886 " struct timeval it_value; /* current value */\n"
891 #: build/C/man2/getitimer.2:64
895 " time_t tv_sec; /* seconds */\n"
896 " suseconds_t tv_usec; /* microseconds */\n"
901 #: build/C/man2/getitimer.2:86
903 "The function B<getitimer>() fills the structure pointed to by I<curr_value> "
904 "with the current setting for the timer specified by I<which> (one of "
905 "B<ITIMER_REAL>, B<ITIMER_VIRTUAL>, or B<ITIMER_PROF>). The element "
906 "I<it_value> is set to the amount of time remaining on the timer, or zero if "
907 "the timer is disabled. Similarly, I<it_interval> is set to the reset value."
911 #: build/C/man2/getitimer.2:94
913 "The function B<setitimer>() sets the specified timer to the value in "
914 "I<new_value>. If I<old_value> is non-NULL, the old value of the timer is "
919 #: build/C/man2/getitimer.2:104
921 "Timers decrement from I<it_value> to zero, generate a signal, and reset to "
922 "I<it_interval>. A timer which is set to zero (I<it_value> is zero or the "
923 "timer expires and I<it_interval> is zero) stops."
927 #: build/C/man2/getitimer.2:110
929 "Both I<tv_sec> and I<tv_usec> are significant in determining the duration of "
934 #: build/C/man2/getitimer.2:122
936 "Timers will never expire before the requested time, but may expire some "
937 "(short) time afterward, which depends on the system timer resolution and on "
938 "the system load; see B<time>(7). (But see BUGS below.) Upon expiration, a "
939 "signal will be generated and the timer reset. If the timer expires while "
940 "the process is active (always true for B<ITIMER_VIRTUAL>), the signal will "
941 "be delivered immediately when generated. Otherwise, the delivery will be "
942 "offset by a small time dependent on the system loading."
946 #: build/C/man2/getitimer.2:127 build/C/man2/killpg.2:94 build/C/man2/tkill.2:99
948 "On success, zero is returned. On error, -1 is returned, and I<errno> is set "
953 #: build/C/man2/getitimer.2:128 build/C/man2/prctl.2:823 build/C/man2/sigaction.2:666 build/C/man2/sigaltstack.2:138 build/C/man2/sigpending.2:60 build/C/man2/sigprocmask.2:100 build/C/man2/sigsuspend.2:77 build/C/man2/timer_settime.2:184 build/C/man2/timerfd_create.2:342
959 #: build/C/man2/getitimer.2:135 build/C/man2/timerfd_create.2:349
960 msgid "I<new_value>, I<old_value>, or I<curr_value> is not valid a pointer."
964 #: build/C/man2/getitimer.2:148
966 "I<which> is not one of B<ITIMER_REAL>, B<ITIMER_VIRTUAL>, or B<ITIMER_PROF>; "
967 "or (since Linux 2.6.22) one of the I<tv_usec> fields in the structure "
968 "pointed to by I<new_value> contains a value outside the range 0 to 999999."
972 #: build/C/man2/getitimer.2:158
974 "POSIX.1-2001, SVr4, 4.4BSD (this call first appeared in 4.2BSD). "
975 "POSIX.1-2008 marks B<getitimer>() and B<setitimer>() obsolete, "
976 "recommending the use of the POSIX timers API (B<timer_gettime>(2), "
977 "B<timer_settime>(2), etc.) instead."
981 #: build/C/man2/getitimer.2:164
983 "A child created via B<fork>(2) does not inherit its parent's interval "
984 "timers. Interval timers are preserved across an B<execve>(2)."
988 #: build/C/man2/getitimer.2:174
990 "POSIX.1 leaves the interaction between B<setitimer>() and the three "
991 "interfaces B<alarm>(2), B<sleep>(3), and B<usleep>(3) unspecified."
995 #: build/C/man2/getitimer.2:176
996 msgid "The standards are silent on the meaning of the call:"
1000 #: build/C/man2/getitimer.2:178
1002 msgid " setitimer(which, NULL, &old_value);\n"
1006 #: build/C/man2/getitimer.2:181
1008 "Many systems (Solaris, the BSDs, and perhaps others) treat this as "
1013 #: build/C/man2/getitimer.2:183
1015 msgid " getitimer(which, &old_value);\n"
1019 #: build/C/man2/getitimer.2:189
1021 "In Linux, this is treated as being equivalent to a call in which the "
1022 "I<new_value> fields are zero; that is, the timer is disabled. I<Don't use "
1023 "this Linux misfeature>: it is nonportable and unnecessary."
1027 #: build/C/man2/getitimer.2:189 build/C/man2/kill.2:161 build/C/man3/profil.3:72 build/C/man3/psignal.3:101 build/C/man2/sigaction.2:781 build/C/man2/signalfd.2:352 build/C/man2/sigpending.2:85 build/C/man3/sigset.3:232 build/C/man2/timer_getoverrun.2:115 build/C/man2/timerfd_create.2:373 build/C/man2/wait.2:536
1033 #: build/C/man2/getitimer.2:198
1035 "The generation and delivery of a signal are distinct, and only one instance "
1036 "of each of the signals listed above may be pending for a process. Under "
1037 "very heavy loading, an B<ITIMER_REAL> timer may expire before the signal "
1038 "from a previous expiration has been delivered. The second signal in such an "
1039 "event will be lost."
1043 #: build/C/man2/getitimer.2:213
1045 "On Linux kernels before 2.6.16, timer values are represented in jiffies. If "
1046 "a request is made set a timer with a value whose jiffies representation "
1047 "exceeds B<MAX_SEC_IN_JIFFIES> (defined in I<include/linux/jiffies.h>), then "
1048 "the timer is silently truncated to this ceiling value. On Linux/i386 "
1049 "(where, since Linux 2.6.13, the default jiffy is 0.004 seconds), this means "
1050 "that the ceiling value for a timer is approximately 99.42 days. Since Linux "
1051 "2.6.16, the kernel uses a different internal representation for times, and "
1052 "this ceiling is removed."
1055 #. 4 Jul 2005: It looks like this bug may remain in 2.4.x.
1056 #. http://lkml.org/lkml/2005/7/1/165
1058 #: build/C/man2/getitimer.2:220
1060 "On certain systems (including i386), Linux kernels before version 2.6.12 "
1061 "have a bug which will produce premature timer expirations of up to one jiffy "
1062 "under some circumstances. This bug is fixed in kernel 2.6.12."
1065 #. Bugzilla report 25 Apr 2006:
1066 #. http://bugzilla.kernel.org/show_bug.cgi?id=6443
1067 #. "setitimer() should reject noncanonical arguments"
1069 #: build/C/man2/getitimer.2:239
1071 "POSIX.1-2001 says that B<setitimer>() should fail if a I<tv_usec> value is "
1072 "specified that is outside of the range 0 to 999999. However, in kernels up "
1073 "to and including 2.6.21, Linux does not give an error, but instead silently "
1074 "adjusts the corresponding seconds value for the timer. From kernel 2.6.22 "
1075 "onward, this nonconformance has been repaired: an improper I<tv_usec> value "
1076 "results in an B<EINVAL> error."
1080 #: build/C/man2/getitimer.2:246
1082 "B<gettimeofday>(2), B<sigaction>(2), B<signal>(2), B<timer_create>(2), "
1083 "B<timerfd_create>(2), B<time>(7)"
1087 #: build/C/man3/gsignal.3:27
1093 #: build/C/man3/gsignal.3:27 build/C/man3/profil.3:28
1099 #: build/C/man3/gsignal.3:30
1100 msgid "gsignal, ssignal - software signal facility"
1104 #: build/C/man3/gsignal.3:33 build/C/man2/kill.2:52 build/C/man3/psignal.3:36 build/C/man3/raise.3:35 build/C/man2/sigaction.2:53 build/C/man3/siginterrupt.3:37 build/C/man3/sigpause.3:31 build/C/man3/sigwait.3:32 build/C/man2/sigwaitinfo.2:31
1106 msgid "B<#include E<lt>signal.hE<gt>>\n"
1110 #: build/C/man3/gsignal.3:35
1112 msgid "B<typedef void (*sighandler_t)(int);>\n"
1116 #: build/C/man3/gsignal.3:37
1118 msgid "B<int gsignal(int >I<signum>B<);>\n"
1122 #: build/C/man3/gsignal.3:39
1124 msgid "B<sighandler_t ssignal(int >I<signum>B<, sighandler_t >I<action>B<);>\n"
1128 #: build/C/man3/gsignal.3:44 build/C/man2/kill.2:59 build/C/man2/killpg.2:53 build/C/man3/profil.3:42 build/C/man3/psignal.3:46 build/C/man2/sigaction.2:61 build/C/man2/sigaltstack.2:38 build/C/man3/siginterrupt.3:44 build/C/man2/sigpending.2:40 build/C/man2/sigprocmask.2:41 build/C/man3/sigqueue.3:39 build/C/man3/sigset.3:45 build/C/man3/sigsetops.3:51 build/C/man2/sigsuspend.2:40 build/C/man3/sigvec.3:45 build/C/man3/sigwait.3:39 build/C/man2/sigwaitinfo.2:41 build/C/man2/timer_create.2:48 build/C/man2/timer_delete.2:41 build/C/man2/timer_getoverrun.2:41 build/C/man2/timer_settime.2:45 build/C/man2/wait.2:69 build/C/man2/wait4.2:53
1129 msgid "Feature Test Macro Requirements for glibc (see B<feature_test_macros>(7)):"
1133 #: build/C/man3/gsignal.3:49
1134 msgid "B<gsignal>(), B<ssignal>(): _SVID_SOURCE"
1138 #: build/C/man3/gsignal.3:57
1140 "Don't use these functions under Linux. Due to a historical mistake, under "
1141 "Linux these functions are aliases for B<raise>(3) and B<signal>(2), "
1146 #: build/C/man3/gsignal.3:95
1148 "Elsewhere, on System V-like systems, these functions implement software "
1149 "signaling, entirely independent of the classical B<signal>(2) and "
1150 "B<kill>(2) functions. The function B<ssignal>() defines the action to "
1151 "take when the software signal with number I<signum> is raised using the "
1152 "function B<gsignal>(), and returns the previous such action or B<SIG_DFL>. "
1153 "The function B<gsignal>() does the following: if no action (or the action "
1154 "B<SIG_DFL>) was specified for I<signum>, then it does nothing and returns "
1155 "0. If the action B<SIG_IGN> was specified for I<signum>, then it does "
1156 "nothing and returns 1. Otherwise, it resets the action to B<SIG_DFL> and "
1157 "calls the action function with argument I<signum>, and returns the value "
1158 "returned by that function. The range of possible values I<signum> varies "
1159 "(often 1-15 or 1-17)."
1163 #: build/C/man3/gsignal.3:103
1165 "These functions are available under AIX, DG/UX, HP-UX, SCO, Solaris, Tru64. "
1166 "They are called obsolete under most of these systems, and are broken under "
1167 "Linux libc and glibc. Some systems also have B<gsignal_r>() and "
1172 #: build/C/man3/gsignal.3:107
1173 msgid "B<kill>(2), B<signal>(2), B<raise>(3)"
1177 #: build/C/man2/kill.2:44
1183 #: build/C/man2/kill.2:44
1189 #: build/C/man2/kill.2:47
1190 msgid "kill - send signal to a process"
1194 #: build/C/man2/kill.2:50
1196 msgid "B<#include E<lt>sys/types.hE<gt>>\n"
1200 #: build/C/man2/kill.2:54
1202 msgid "B<int kill(pid_t >I<pid>B<, int >I<sig>B<);>\n"
1206 #: build/C/man2/kill.2:64
1207 msgid "B<kill>(): _POSIX_C_SOURCE\\ E<gt>=\\ 1 || _XOPEN_SOURCE || _POSIX_SOURCE"
1211 #: build/C/man2/kill.2:70
1213 "The B<kill>() system call can be used to send any signal to any process "
1218 #: build/C/man2/kill.2:73
1220 "If I<pid> is positive, then signal I<sig> is sent to the process with the ID "
1221 "specified by I<pid>."
1225 #: build/C/man2/kill.2:76
1227 "If I<pid> equals 0, then I<sig> is sent to every process in the process "
1228 "group of the calling process."
1232 #: build/C/man2/kill.2:80
1234 "If I<pid> equals -1, then I<sig> is sent to every process for which the "
1235 "calling process has permission to send signals, except for process 1 "
1236 "(I<init>), but see below."
1240 #: build/C/man2/kill.2:83
1242 "If I<pid> is less than -1, then I<sig> is sent to every process in the "
1243 "process group whose ID is I<-pid>."
1247 #: build/C/man2/kill.2:88
1249 "If I<sig> is 0, then no signal is sent, but error checking is still "
1250 "performed; this can be used to check for the existence of a process ID or "
1255 #: build/C/man2/kill.2:100
1257 "For a process to have permission to send a signal it must either be "
1258 "privileged (under Linux: have the B<CAP_KILL> capability), or the real or "
1259 "effective user ID of the sending process must equal the real or saved "
1260 "set-user-ID of the target process. In the case of B<SIGCONT> it suffices "
1261 "when the sending and receiving processes belong to the same session. "
1262 "(Historically, the rules were different; see NOTES.)"
1266 #: build/C/man2/kill.2:105
1268 "On success (at least one signal was sent), zero is returned. On error, -1 "
1269 "is returned, and I<errno> is set appropriately."
1273 #: build/C/man2/kill.2:109
1274 msgid "An invalid signal was specified."
1278 #: build/C/man2/kill.2:109 build/C/man2/killpg.2:99 build/C/man2/prctl.2:985 build/C/man2/prctl.2:997 build/C/man2/prctl.2:1007 build/C/man2/prctl.2:1015 build/C/man2/rt_sigqueueinfo.2:148 build/C/man2/sigaltstack.2:153 build/C/man3/sigqueue.3:102 build/C/man2/tkill.2:103
1284 #: build/C/man2/kill.2:113 build/C/man2/killpg.2:103
1286 "The process does not have permission to send the signal to any of the target "
1291 #: build/C/man2/kill.2:113 build/C/man2/killpg.2:103 build/C/man2/killpg.2:107 build/C/man2/rt_sigqueueinfo.2:156 build/C/man3/sigqueue.3:108 build/C/man2/tkill.2:108
1297 #: build/C/man2/kill.2:121
1299 "The pid or process group does not exist. Note that an existing process "
1300 "might be a zombie, a process which already committed termination, but has "
1301 "not yet been B<wait>(2)ed for."
1305 #: build/C/man2/kill.2:123 build/C/man2/pause.2:59 build/C/man2/wait.2:424
1306 msgid "SVr4, 4.3BSD, POSIX.1-2001."
1310 #: build/C/man2/kill.2:131
1312 "The only signals that can be sent to process ID 1, the I<init> process, are "
1313 "those for which I<init> has explicitly installed signal handlers. This is "
1314 "done to assure the system is not brought down accidentally."
1318 #: build/C/man2/kill.2:137
1320 "POSIX.1-2001 requires that I<kill(-1,sig)> send I<sig> to all processes that "
1321 "the calling process may send signals to, except possibly for some "
1322 "implementation-defined system processes. Linux allows a process to signal "
1323 "itself, but on Linux the call I<kill(-1,sig)> does not signal the calling "
1328 #: build/C/man2/kill.2:147
1330 "POSIX.1-2001 requires that if a process sends a signal to itself, and the "
1331 "sending thread does not have the signal blocked, and no other thread has it "
1332 "unblocked or is waiting for it in B<sigwait>(3), at least one unblocked "
1333 "signal must be delivered to the sending thread before the B<kill>() "
1338 #: build/C/man2/kill.2:147 build/C/man3/sigpause.3:82 build/C/man2/wait.2:479
1343 #. In the 0.* kernels things chopped and changed quite
1344 #. a bit - MTK, 24 Jul 02
1346 #: build/C/man2/kill.2:161
1348 "Across different kernel versions, Linux has enforced different rules for the "
1349 "permissions required for an unprivileged process to send a signal to another "
1350 "process. In kernels 1.0 to 1.2.2, a signal could be sent if the effective "
1351 "user ID of the sender matched effective user ID of the target, or the real "
1352 "user ID of the sender matched the real user ID of the target. From kernel "
1353 "1.2.3 until 1.3.77, a signal could be sent if the effective user ID of the "
1354 "sender matched either the real or effective user ID of the target. The "
1355 "current rules, which conform to POSIX.1-2001, were adopted in kernel 1.3.78."
1359 #: build/C/man2/kill.2:171
1361 "In 2.6 kernels up to and including 2.6.7, there was a bug that meant that "
1362 "when sending signals to a process group, B<kill>() failed with the error "
1363 "B<EPERM> if the caller did not have permission to send the signal to I<any> "
1364 "(rather than I<all>) of the members of the process group. Notwithstanding "
1365 "this error return, the signal was still delivered to all of the processes "
1366 "for which the caller had permission to signal."
1370 #: build/C/man2/kill.2:181
1372 "B<_exit>(2), B<killpg>(2), B<signal>(2), B<tkill>(2), B<exit>(3), "
1373 "B<sigqueue>(3), B<capabilities>(7), B<credentials>(7), B<signal>(7)"
1377 #: build/C/man2/killpg.2:42
1383 #: build/C/man2/killpg.2:42 build/C/man3/sigset.3:26
1389 #: build/C/man2/killpg.2:45
1390 msgid "killpg - send signal to a process group"
1394 #: build/C/man2/killpg.2:49
1395 msgid "B<int killpg(int >I<pgrp>B<, int >I<sig>B<);>"
1399 #: build/C/man2/killpg.2:55
1401 msgid "B<killpg>():"
1405 #: build/C/man2/killpg.2:59 build/C/man2/sigaltstack.2:46 build/C/man3/siginterrupt.3:51 build/C/man2/wait4.2:60
1407 "_BSD_SOURCE || _XOPEN_SOURCE\\ E<gt>=\\ 500 || _XOPEN_SOURCE\\ &&\\ "
1408 "_XOPEN_SOURCE_EXTENDED"
1412 #: build/C/man2/killpg.2:69
1414 "B<killpg>() sends the signal I<sig> to the process group I<pgrp>. See "
1415 "B<signal>(7) for a list of signals."
1419 #: build/C/man2/killpg.2:78
1421 "If I<pgrp> is 0, B<killpg>() sends the signal to the calling process's "
1422 "process group. (POSIX says: If I<pgrp> is less than or equal to 1, the "
1423 "behavior is undefined.)"
1427 #: build/C/man2/killpg.2:89
1429 "For a process to have permission to send a signal it must either be "
1430 "privileged (under Linux: have the B<CAP_KILL> capability), or the real or "
1431 "effective user ID of the sending process must equal the real or saved "
1432 "set-user-ID of the target process. In the case of B<SIGCONT> it suffices "
1433 "when the sending and receiving processes belong to the same session."
1437 #: build/C/man2/killpg.2:99
1438 msgid "I<sig> is not a valid signal number."
1442 #: build/C/man2/killpg.2:107
1443 msgid "No process can be found in the process group specified by I<pgrp>."
1447 #: build/C/man2/killpg.2:111
1449 "The process group was given as 0 but the sending process does not have a "
1454 #: build/C/man2/killpg.2:115
1456 "SVr4, 4.4BSD (the B<killpg>() function call first appeared in 4BSD), "
1461 #: build/C/man2/killpg.2:129
1463 "There are various differences between the permission checking in BSD-type "
1464 "systems and System\\ V-type systems. See the POSIX rationale for "
1465 "B<kill>(). A difference not mentioned by POSIX concerns the return value "
1466 "B<EPERM>: BSD documents that no signal is sent and B<EPERM> returned when "
1467 "the permission check failed for at least one target process, while POSIX "
1468 "documents B<EPERM> only when the permission check failed for all target "
1473 #: build/C/man2/killpg.2:134
1475 "On Linux, B<killpg>() is implemented as a library function that makes the "
1476 "call I<kill(-pgrp,\\ sig)>."
1480 #: build/C/man2/killpg.2:140
1482 "B<getpgrp>(2), B<kill>(2), B<signal>(2), B<capabilities>(7), "
1487 #: build/C/man2/pause.2:30
1493 #: build/C/man2/pause.2:30
1499 #: build/C/man2/pause.2:33
1500 msgid "pause - wait for signal"
1504 #: build/C/man2/pause.2:35
1505 msgid "B<#include E<lt>unistd.hE<gt>>"
1509 #: build/C/man2/pause.2:37
1510 msgid "B<int pause(void);>"
1514 #: build/C/man2/pause.2:42
1516 "B<pause>() causes the calling process (or thread) to sleep until a signal "
1517 "is delivered that either terminates the process or causes the invocation of "
1518 "a signal-catching function."
1521 #. .BR ERESTARTNOHAND .
1523 #: build/C/man2/pause.2:53
1525 "B<pause>() returns only when a signal was caught and the signal-catching "
1526 "function returned. In this case, B<pause>() returns -1, and I<errno> is "
1531 #: build/C/man2/pause.2:54 build/C/man2/sigsuspend.2:81 build/C/man2/sigwaitinfo.2:123 build/C/man2/wait.2:410
1537 #: build/C/man2/pause.2:57
1538 msgid "a signal was caught and the signal-catching function returned."
1542 #: build/C/man2/pause.2:64
1543 msgid "B<kill>(2), B<select>(2), B<signal>(2), B<sigsuspend>(2)"
1547 #: build/C/man2/prctl.2:52
1553 #: build/C/man2/prctl.2:52 build/C/man3/sigsetops.3:31
1559 #: build/C/man2/prctl.2:55
1560 msgid "prctl - operations on a process"
1564 #: build/C/man2/prctl.2:58
1566 msgid "B<#include E<lt>sys/prctl.hE<gt>>\n"
1570 #: build/C/man2/prctl.2:61
1573 "B<int prctl(int >I<option>B<, unsigned long >I<arg2>B<, unsigned long "
1575 "B< unsigned long >I<arg4>B<, unsigned long >I<arg5>B<);>\n"
1579 #: build/C/man2/prctl.2:68
1581 "B<prctl>() is called with a first argument describing what to do (with "
1582 "values defined in I<E<lt>linux/prctl.hE<gt>>), and further arguments with a "
1583 "significance depending on the first one. The first argument can be:"
1587 #: build/C/man2/prctl.2:68
1589 msgid "B<PR_CAPBSET_READ> (since Linux 2.6.25)"
1593 #: build/C/man2/prctl.2:80
1595 "Return (as the function result) 1 if the capability specified in I<arg2> is "
1596 "in the calling thread's capability bounding set, or 0 if it is not. (The "
1597 "capability constants are defined in I<E<lt>linux/capability.hE<gt>>.) The "
1598 "capability bounding set dictates whether the process can receive the "
1599 "capability through a file's permitted capability set on a subsequent call to "
1604 #: build/C/man2/prctl.2:85
1606 "If the capability specified in I<arg2> is not valid, then the call fails "
1607 "with the error B<EINVAL>."
1611 #: build/C/man2/prctl.2:85
1613 msgid "B<PR_CAPBSET_DROP> (since Linux 2.6.25)"
1617 #: build/C/man2/prctl.2:94
1619 "If the calling thread has the B<CAP_SETPCAP> capability, then drop the "
1620 "capability specified by I<arg2> from the calling thread's capability "
1621 "bounding set. Any children of the calling thread will inherit the newly "
1622 "reduced bounding set."
1626 #: build/C/man2/prctl.2:106
1628 "The call fails with the error: B<EPERM> if the calling thread does not have "
1629 "the B<CAP_SETPCAP>; B<EINVAL> if I<arg2> does not represent a valid "
1630 "capability; or B<EINVAL> if file capabilities are not enabled in the kernel, "
1631 "in which case bounding sets are not supported."
1635 #: build/C/man2/prctl.2:106
1637 msgid "B<PR_SET_CHILD_SUBREAPER> (since Linux 3.4)"
1640 #. commit ebec18a6d3aa1e7d84aab16225e87fd25170ec2b
1642 #: build/C/man2/prctl.2:131
1644 "If I<arg2> is nonzero, set the \"child subreaper\" attribute of the calling "
1645 "process; if I<arg2> is zero, unset the attribute. When a process is marked "
1646 "as a child subreaper, all of the children that it creates, and their "
1647 "descendants, will be marked as having a subreaper. In effect, a subreaper "
1648 "fulfills the role of B<init>(1) for its descendant processes. Upon "
1649 "termination of a process that is orphaned (i.e., its immediate parent has "
1650 "already terminated) and marked as having a subreaper, the nearest still "
1651 "living ancestor subreaper will receive a B<SIGCHLD> signal and be able to "
1652 "B<wait>(2) on the process to discover its termination status."
1656 #: build/C/man2/prctl.2:131
1658 msgid "B<PR_GET_CHILD_SUBREAPER> (since Linux 3.4)"
1662 #: build/C/man2/prctl.2:136
1664 "Return the \"child subreaper\" setting of the caller, in the location "
1665 "pointed to by I<(int\\ *) arg2>."
1669 #: build/C/man2/prctl.2:136
1671 msgid "B<PR_SET_DUMPABLE> (since Linux 2.3.20)"
1674 #. See http://marc.theaimsgroup.com/?l=linux-kernel&m=115270289030630&w=2
1675 #. Subject: Fix prctl privilege escalation (CVE-2006-2451)
1676 #. From: Marcel Holtmann <marcel () holtmann ! org>
1677 #. Date: 2006-07-12 11:12:00
1679 #: build/C/man2/prctl.2:162
1681 "Set the state of the flag determining whether core dumps are produced for "
1682 "the calling process upon delivery of a signal whose default behavior is to "
1683 "produce a core dump. (Normally, this flag is set for a process by default, "
1684 "but it is cleared when a set-user-ID or set-group-ID program is executed and "
1685 "also by various system calls that manipulate process UIDs and GIDs). In "
1686 "kernels up to and including 2.6.12, I<arg2> must be either 0 (process is not "
1687 "dumpable) or 1 (process is dumpable). Between kernels 2.6.13 and 2.6.17, "
1688 "the value 2 was also permitted, which caused any binary which normally would "
1689 "not be dumped to be dumped readable by root only; for security reasons, this "
1690 "feature has been removed. (See also the description of "
1691 "I</proc/sys/fs/suid_dumpable> in B<proc>(5).) Processes that are not "
1692 "dumpable can not be attached via B<ptrace>(2) B<PTRACE_ATTACH>."
1696 #: build/C/man2/prctl.2:162
1698 msgid "B<PR_GET_DUMPABLE> (since Linux 2.3.20)"
1701 #. Since Linux 2.6.13, the dumpable flag can have the value 2,
1702 #. but in 2.6.13 PR_GET_DUMPABLE simply returns 1 if the dumpable
1703 #. flags has a nonzero value. This was fixed in 2.6.14.
1705 #: build/C/man2/prctl.2:169
1707 "Return (as the function result) the current state of the calling process's "
1712 #: build/C/man2/prctl.2:169
1714 msgid "B<PR_SET_ENDIAN> (since Linux 2.6.18, PowerPC only)"
1717 #. Respectively 0, 1, 2
1719 #: build/C/man2/prctl.2:179
1721 "Set the endian-ness of the calling process to the value given in I<arg2>, "
1722 "which should be one of the following: B<PR_ENDIAN_BIG>, B<PR_ENDIAN_LITTLE>, "
1723 "or B<PR_ENDIAN_PPC_LITTLE> (PowerPC pseudo little endian)."
1727 #: build/C/man2/prctl.2:179
1729 msgid "B<PR_GET_ENDIAN> (since Linux 2.6.18, PowerPC only)"
1733 #: build/C/man2/prctl.2:184
1735 "Return the endian-ness of the calling process, in the location pointed to by "
1736 "I<(int\\ *) arg2>."
1740 #: build/C/man2/prctl.2:184
1742 msgid "B<PR_SET_FPEMU> (since Linux 2.4.18, 2.5.9, only on ia64)"
1746 #: build/C/man2/prctl.2:191
1748 "Set floating-point emulation control bits to I<arg2>. Pass "
1749 "B<PR_FPEMU_NOPRINT> to silently emulate fp operations accesses, or "
1750 "B<PR_FPEMU_SIGFPE> to not emulate fp operations and send B<SIGFPE> instead."
1754 #: build/C/man2/prctl.2:191
1756 msgid "B<PR_GET_FPEMU> (since Linux 2.4.18, 2.5.9, only on ia64)"
1760 #: build/C/man2/prctl.2:196
1762 "Return floating-point emulation control bits, in the location pointed to by "
1763 "I<(int\\ *) arg2>."
1767 #: build/C/man2/prctl.2:196
1769 msgid "B<PR_SET_FPEXC> (since Linux 2.4.21, 2.5.32, only on PowerPC)"
1773 #: build/C/man2/prctl.2:209
1775 "Set floating-point exception mode to I<arg2>. Pass B<PR_FP_EXC_SW_ENABLE> "
1776 "to use FPEXC for FP exception enables, B<PR_FP_EXC_DIV> for floating-point "
1777 "divide by zero, B<PR_FP_EXC_OVF> for floating-point overflow, "
1778 "B<PR_FP_EXC_UND> for floating-point underflow, B<PR_FP_EXC_RES> for "
1779 "floating-point inexact result, B<PR_FP_EXC_INV> for floating-point invalid "
1780 "operation, B<PR_FP_EXC_DISABLED> for FP exceptions disabled, "
1781 "B<PR_FP_EXC_NONRECOV> for async nonrecoverable exception mode, "
1782 "B<PR_FP_EXC_ASYNC> for async recoverable exception mode, "
1783 "B<PR_FP_EXC_PRECISE> for precise exception mode."
1787 #: build/C/man2/prctl.2:209
1789 msgid "B<PR_GET_FPEXC> (since Linux 2.4.21, 2.5.32, only on PowerPC)"
1793 #: build/C/man2/prctl.2:214
1795 "Return floating-point exception mode, in the location pointed to by I<(int\\ "
1800 #: build/C/man2/prctl.2:214
1802 msgid "B<PR_SET_KEEPCAPS> (since Linux 2.2.18)"
1806 #: build/C/man2/prctl.2:232
1808 "Set the state of the thread's \"keep capabilities\" flag, which determines "
1809 "whether the threads's permitted capability set is cleared when a change is "
1810 "made to the threads's user IDs such that the threads's real UID, effective "
1811 "UID, and saved set-user-ID all become nonzero when at least one of them "
1812 "previously had the value 0. By default, the permitted capability set is "
1813 "cleared when such a change is made; setting the \"keep capabilities\" flag "
1814 "prevents it from being cleared. I<arg2> must be either 0 (permitted "
1815 "capabilities are cleared) or 1 (permitted capabilities are kept). (A "
1816 "thread's I<effective> capability set is always cleared when such a "
1817 "credential change is made, regardless of the setting of the \"keep "
1818 "capabilities\" flag.) The \"keep capabilities\" value will be reset to 0 on "
1819 "subsequent calls to B<execve>(2)."
1823 #: build/C/man2/prctl.2:232
1825 msgid "B<PR_GET_KEEPCAPS> (since Linux 2.2.18)"
1829 #: build/C/man2/prctl.2:236
1831 "Return (as the function result) the current state of the calling threads's "
1832 "\"keep capabilities\" flag."
1836 #: build/C/man2/prctl.2:236
1838 msgid "B<PR_SET_NAME> (since Linux 2.6.9)"
1841 #. TASK_COMM_LEN in include/linux/sched.h
1843 #: build/C/man2/prctl.2:253
1845 "Set the name of the calling thread, using the value in the location pointed "
1846 "to by I<(char\\ *) arg2>. The name can be up to 16 bytes long, and should "
1847 "be null-terminated if it contains fewer bytes. This is the same attribute "
1848 "that can be set via B<pthread_setname_np>(3) and retrieved using "
1849 "B<pthread_getname_np>(3). The attribute is likewise accessible via "
1850 "I</proc/self/task/[tid]/comm>, where I<tid> is the name of the calling "
1855 #: build/C/man2/prctl.2:253
1857 msgid "B<PR_GET_NAME> (since Linux 2.6.11)"
1861 #: build/C/man2/prctl.2:260
1863 "Return the name of the calling thread, in the buffer pointed to by I<(char\\ "
1864 "*) arg2>. The buffer should allow space for up to 16 bytes; the returned "
1865 "string will be null-terminated if it is shorter than that."
1869 #: build/C/man2/prctl.2:260
1871 msgid "B<PR_SET_NO_NEW_PRIVS> (since Linux 3.5)"
1875 #: build/C/man2/prctl.2:283
1877 "Set the calling process's I<no_new_privs> bit to the value in I<arg2>. With "
1878 "I<no_new_privs> set to 1, B<execve>(2) promises not to grant privileges to "
1879 "do anything that could not have been done without the B<execve>(2) call "
1880 "(for example, rendering the set-user-ID and set-group-ID permission bits, "
1881 "and file capabilities non-functional). Once set, this bit cannot be unset. "
1882 "The setting of this bit is inherited by children created by B<fork>(2) and "
1883 "B<clone>(2), and preserved across B<execve>(2)."
1887 #: build/C/man2/prctl.2:286
1889 "For more information, see the kernel source file "
1890 "I<Documentation/prctl/no_new_privs.txt>."
1894 #: build/C/man2/prctl.2:286
1896 msgid "B<PR_GET_NO_NEW_PRIVS> (since Linux 3.5)"
1900 #: build/C/man2/prctl.2:297
1902 "Return (as the function result) the value of the I<no_new_privs> bit for the "
1903 "current process. A value of 0 indicates the regular B<execve>(2) "
1904 "behavior. A value of 1 indicates B<execve>(2) will operate in the "
1905 "privilege-restricting mode described above."
1909 #: build/C/man2/prctl.2:297
1911 msgid "B<PR_SET_PDEATHSIG> (since Linux 2.1.57)"
1915 #: build/C/man2/prctl.2:310
1917 "Set the parent process death signal of the calling process to I<arg2> "
1918 "(either a signal value in the range 1..maxsig, or 0 to clear). This is the "
1919 "signal that the calling process will get when its parent dies. This value "
1920 "is cleared for the child of a B<fork>(2) and (since Linux 2.4.36 / 2.6.23) "
1921 "when executing a set-user-ID or set-group-ID binary. This value is "
1922 "preserved across B<execve>(2)."
1926 #: build/C/man2/prctl.2:310
1928 msgid "B<PR_GET_PDEATHSIG> (since Linux 2.3.15)"
1932 #: build/C/man2/prctl.2:315
1934 "Return the current value of the parent process death signal, in the location "
1935 "pointed to by I<(int\\ *) arg2>."
1939 #: build/C/man2/prctl.2:315
1941 msgid "B<PR_SET_PTRACER> (since Linux 3.4)"
1944 #. commit 2d514487faf188938a4ee4fb3464eeecfbdcf8eb
1945 #. commit bf06189e4d14641c0148bea16e9dd24943862215
1947 #: build/C/man2/prctl.2:340
1949 "This is meaningful only when the Yama LSM is enabled and in mode 1 "
1950 "(\"restricted ptrace\", visible via I</proc/sys/kernel/yama/ptrace_scope>). "
1951 "When a \"ptracer process ID\" is passed in I<arg2>, the caller is declaring "
1952 "that the ptracer process can B<ptrace>(2) the calling process as if it were "
1953 "a direct process ancestor. Each B<PR_SET_PTRACER> operation replaces the "
1954 "previous \"ptracer process ID\". Employing B<PR_SET_PTRACER> with I<arg2> "
1955 "set to 0 clears the caller's \"ptracer process ID\". If I<arg2> is "
1956 "B<PR_SET_PTRACER_ANY>, the ptrace restrictions introduced by Yama are "
1957 "effectively disabled for the calling process."
1961 #: build/C/man2/prctl.2:343
1963 "For further information, see the kernel source file "
1964 "I<Documentation/security/Yama.txt>."
1968 #: build/C/man2/prctl.2:343
1970 msgid "B<PR_SET_SECCOMP> (since Linux 2.6.23)"
1973 #. See http://thread.gmane.org/gmane.linux.kernel/542632
1974 #. [PATCH 0 of 2] seccomp updates
1975 #. andrea@cpushare.com
1977 #: build/C/man2/prctl.2:354
1979 "Set the secure computing (seccomp) mode for the calling thread, to limit the "
1980 "available system calls. The seccomp mode is selected via I<arg2>. (The "
1981 "seccomp constants are defined in I<E<lt>linux/seccomp.hE<gt>>.)"
1985 #: build/C/man2/prctl.2:375
1987 "With I<arg2> set to B<SECCOMP_MODE_STRICT> the only system calls that the "
1988 "thread is permitted to make are B<read>(2), B<write>(2), B<_exit>(2), and "
1989 "B<sigreturn>(2). Other system calls result in the delivery of a B<SIGKILL> "
1990 "signal. Strict secure computing mode is useful for number-crunching "
1991 "applications that may need to execute untrusted byte code, perhaps obtained "
1992 "by reading from a pipe or socket. This operation is available only if the "
1993 "kernel is configured with B<CONFIG_SECCOMP> enabled."
1997 #: build/C/man2/prctl.2:390
1999 "With I<arg2> set to B<SECCOMP_MODE_FILTER> (since Linux 3.5) the system "
2000 "calls allowed are defined by a pointer to a Berkeley Packet Filter passed in "
2001 "I<arg3>. This argument is a pointer to I<struct sock_fprog>; it can be "
2002 "designed to filter arbitrary system calls and system call arguments. This "
2003 "mode is available only if the kernel is configured with "
2004 "B<CONFIG_SECCOMP_FILTER> enabled."
2008 #: build/C/man2/prctl.2:405
2010 "If B<SECCOMP_MODE_FILTER> filters permit B<fork>(2), then the seccomp mode "
2011 "is inherited by children created by B<fork>(2); if B<execve>(2) is "
2012 "permitted, then the seccomp mode is preserved across B<execve>(2). If the "
2013 "filters permit B<prctl>() calls, then additional filters can be added; they "
2014 "are run in order until the first non-allow result is seen."
2018 #: build/C/man2/prctl.2:408
2020 "For further information, see the kernel source file "
2021 "I<Documentation/prctl/seccomp_filter.txt>."
2025 #: build/C/man2/prctl.2:408
2027 msgid "B<PR_GET_SECCOMP> (since Linux 2.6.23)"
2031 #: build/C/man2/prctl.2:424
2033 "Return (as the function result) the secure computing mode of the calling "
2034 "thread. If the caller is not in secure computing mode, this operation "
2035 "returns 0; if the caller is in strict secure computing mode, then the "
2036 "B<prctl>() call will cause a B<SIGKILL> signal to be sent to the process. "
2037 "If the caller is in filter mode, and this system call is allowed by the "
2038 "seccomp filters, it returns 2. This operation is available only if the "
2039 "kernel is configured with B<CONFIG_SECCOMP> enabled."
2043 #: build/C/man2/prctl.2:424
2045 msgid "B<PR_SET_SECUREBITS> (since Linux 2.6.26)"
2049 #: build/C/man2/prctl.2:430
2051 "Set the \"securebits\" flags of the calling thread to the value supplied in "
2052 "I<arg2>. See B<capabilities>(7)."
2056 #: build/C/man2/prctl.2:430
2058 msgid "B<PR_GET_SECUREBITS> (since Linux 2.6.26)"
2062 #: build/C/man2/prctl.2:436
2064 "Return (as the function result) the \"securebits\" flags of the calling "
2065 "thread. See B<capabilities>(7)."
2069 #: build/C/man2/prctl.2:436
2071 msgid "B<PR_SET_THP_DISABLE> (since Linux 3.15)"
2074 #. commit a0715cc22601e8830ace98366c0c2bd8da52af52
2076 #: build/C/man2/prctl.2:452
2078 "Set the state of the \"THP disable\" flag for the calling thread. If "
2079 "I<arg2> has a nonzero value, the flag is set, otherwise it is cleared. "
2080 "Setting this flag provides a method for disabling transparent huge pages for "
2081 "jobs where the code cannot be modified, and using a malloc hook with "
2082 "B<madvise>(2) is not an option (i.e., statically allocated data). The "
2083 "setting of the \"THP disable\" flag is inherited by a child created via "
2084 "B<fork>(2) and is preserved across B<execve>(2)."
2088 #: build/C/man2/prctl.2:452
2090 msgid "B<PR_GET_THP_DISABLE> (since Linux 3.15)"
2094 #: build/C/man2/prctl.2:457
2096 "Return (via the function result) the current setting of the \"THP disable\" "
2097 "flag for the calling thread: either 1, if the flag is set, or 0, if it is "
2102 #: build/C/man2/prctl.2:457
2104 msgid "B<PR_GET_TID_ADDRESS> (since Linux 3.5)"
2107 #. commit 300f786b2683f8bb1ec0afb6e1851183a479c86d
2109 #: build/C/man2/prctl.2:472
2111 "Retrieve the I<clear_child_tid> address set by B<set_tid_address>(2) and "
2112 "the B<clone>(2) B<CLONE_CHILD_CLEARTID> flag, in the location pointed to by "
2113 "I<(int\\ **)\\ arg2>. This feature is available only if the kernel is built "
2114 "with the B<CONFIG_CHECKPOINT_RESTORE> option enabled."
2118 #: build/C/man2/prctl.2:472
2120 msgid "B<PR_SET_TIMERSLACK> (since Linux 2.6.28)"
2123 #. See https://lwn.net/Articles/369549/
2124 #. commit 6976675d94042fbd446231d1bd8b7de71a980ada
2125 #. It seems that it's not possible to set the timer slack to zero;
2126 #. The minimum value is 1? Seems a little strange.
2128 #: build/C/man2/prctl.2:491
2130 "Set the current timer slack for the calling thread to the nanosecond value "
2131 "supplied in I<arg2>. If I<arg2> is less than or equal to zero, reset the "
2132 "current timer slack to the thread's default timer slack value. The timer "
2133 "slack is used by the kernel to group timer expirations for the calling "
2134 "thread that are close to one another; as a consequence, timer expirations "
2135 "for the thread may be up to the specified number of nanoseconds late (but "
2136 "will never expire early). Grouping timer expirations can help reduce system "
2137 "power consumption by minimizing CPU wake-ups."
2140 #. List obtained by grepping for futex usage in glibc source
2142 #: build/C/man2/prctl.2:511
2144 "The timer expirations affected by timer slack are those set by B<select>(2), "
2145 "B<pselect>(2), B<poll>(2), B<ppoll>(2), B<epoll_wait>(2), B<epoll_pwait>(2), "
2146 "B<clock_nanosleep>(2), B<nanosleep>(2), and B<futex>(2) (and thus the "
2147 "library functions implemented via futexes, including "
2148 "B<pthread_cond_timedwait>(3), B<pthread_mutex_timedlock>(3), "
2149 "B<pthread_rwlock_timedrdlock>(3), B<pthread_rwlock_timedwrlock>(3), and "
2150 "B<sem_timedwait>(3))."
2154 #: build/C/man2/prctl.2:515
2156 "Timer slack is not applied to threads that are scheduled under a real-time "
2157 "scheduling policy (see B<sched_setscheduler>(2))."
2161 #: build/C/man2/prctl.2:532
2163 "Each thread has two associated timer slack values: a \"default\" value, and "
2164 "a \"current\" value. The current value is the one that governs grouping of "
2165 "timer expirations. When a new thread is created, the two timer slack values "
2166 "are made the same as the current value of the creating thread. Thereafter, "
2167 "a thread can adjust its current timer slack value via B<PR_SET_TIMERSLACK> "
2168 "(the default value can't be changed). The timer slack values of I<init> "
2169 "(PID 1), the ancestor of all processes, are 50,000 nanoseconds (50 "
2170 "microseconds). The timer slack values are preserved across B<execve>(2)."
2174 #: build/C/man2/prctl.2:532
2176 msgid "B<PR_GET_TIMERSLACK> (since Linux 2.6.28)"
2180 #: build/C/man2/prctl.2:536
2182 "Return (as the function result) the current timer slack value of the "
2187 #: build/C/man2/prctl.2:536
2189 msgid "B<PR_SET_TIMING> (since Linux 2.6.0-test4)"
2194 #. PR_TIMING_TIMESTAMP doesn't do anything in 2.6.26-rc8,
2195 #. and looking at the patch history, it appears
2196 #. that it never did anything.
2198 #: build/C/man2/prctl.2:553
2200 "Set whether to use (normal, traditional) statistical process timing or "
2201 "accurate timestamp-based process timing, by passing B<PR_TIMING_STATISTICAL> "
2202 "or B<PR_TIMING_TIMESTAMP> to I<arg2>. B<PR_TIMING_TIMESTAMP> is not "
2203 "currently implemented (attempting to set this mode will yield the error "
2208 #: build/C/man2/prctl.2:553
2210 msgid "B<PR_GET_TIMING> (since Linux 2.6.0-test4)"
2214 #: build/C/man2/prctl.2:557
2216 "Return (as the function result) which process timing method is currently in "
2221 #: build/C/man2/prctl.2:557
2223 msgid "B<PR_TASK_PERF_EVENTS_DISABLE> (since Linux 2.6.31)"
2227 #: build/C/man2/prctl.2:566
2229 "Disable all performance counters attached to the calling process, regardless "
2230 "of whether the counters were created by this process or another process. "
2231 "Performance counters created by the calling process for other processes are "
2232 "unaffected. For more information on performance counters, see the Linux "
2233 "kernel source file I<tools/perf/design.txt>."
2236 #. commit 1d1c7ddbfab358445a542715551301b7fc363e28
2238 #: build/C/man2/prctl.2:572
2240 "Originally called B<PR_TASK_PERF_COUNTERS_DISABLE>; renamed (with same "
2241 "numerical value) in Linux 2.6.32."
2245 #: build/C/man2/prctl.2:572
2247 msgid "B<PR_TASK_PERF_EVENTS_ENABLE> (since Linux 2.6.31)"
2251 #: build/C/man2/prctl.2:577
2253 "The converse of B<PR_TASK_PERF_EVENTS_DISABLE>; enable performance counters "
2254 "attached to the calling process."
2257 #. commit 1d1c7ddbfab358445a542715551301b7fc363e28
2258 #. commit cdd6c482c9ff9c55475ee7392ec8f672eddb7be6
2260 #: build/C/man2/prctl.2:584
2261 msgid "Originally called B<PR_TASK_PERF_COUNTERS_ENABLE>; renamed in Linux 2.6.32."
2265 #: build/C/man2/prctl.2:584
2267 msgid "B<PR_SET_TSC> (since Linux 2.6.26, x86 only)"
2271 #: build/C/man2/prctl.2:597
2273 "Set the state of the flag determining whether the timestamp counter can be "
2274 "read by the process. Pass B<PR_TSC_ENABLE> to I<arg2> to allow it to be "
2275 "read, or B<PR_TSC_SIGSEGV> to generate a B<SIGSEGV> when the process tries "
2276 "to read the timestamp counter."
2280 #: build/C/man2/prctl.2:597
2282 msgid "B<PR_GET_TSC> (since Linux 2.6.26, x86 only)"
2286 #: build/C/man2/prctl.2:603
2288 "Return the state of the flag determining whether the timestamp counter can "
2289 "be read, in the location pointed to by I<(int\\ *) arg2>."
2293 #: build/C/man2/prctl.2:603
2295 msgid "B<PR_SET_UNALIGN>"
2299 #: build/C/man2/prctl.2:613
2301 "(Only on: ia64, since Linux 2.3.48; parisc, since Linux 2.6.15; PowerPC, "
2302 "since Linux 2.6.18; Alpha, since Linux 2.6.22) Set unaligned access control "
2303 "bits to I<arg2>. Pass B<PR_UNALIGN_NOPRINT> to silently fix up unaligned "
2304 "user accesses, or B<PR_UNALIGN_SIGBUS> to generate B<SIGBUS> on unaligned "
2309 #: build/C/man2/prctl.2:613
2311 msgid "B<PR_GET_UNALIGN>"
2315 #: build/C/man2/prctl.2:620
2317 "(see B<PR_SET_UNALIGN> for information on versions and architectures) "
2318 "Return unaligned access control bits, in the location pointed to by I<(int\\ "
2323 #: build/C/man2/prctl.2:620
2325 msgid "B<PR_MCE_KILL> (since Linux 2.6.32)"
2329 #: build/C/man2/prctl.2:660
2331 "Set the machine check memory corruption kill policy for the current thread. "
2332 "If I<arg2> is B<PR_MCE_KILL_CLEAR>, clear the thread memory corruption kill "
2333 "policy and use the system-wide default. (The system-wide default is defined "
2334 "by I</proc/sys/vm/memory_failure_early_kill>; see B<proc>(5).) If I<arg2> "
2335 "is B<PR_MCE_KILL_SET>, use a thread-specific memory corruption kill policy. "
2336 "In this case, I<arg3> defines whether the policy is I<early kill> "
2337 "(B<PR_MCE_KILL_EARLY>), I<late kill> (B<PR_MCE_KILL_LATE>), or the "
2338 "system-wide default (B<PR_MCE_KILL_DEFAULT>). Early kill means that the "
2339 "thread receives a B<SIGBUS> signal as soon as hardware memory corruption is "
2340 "detected inside its address space. In late kill mode, the process is killed "
2341 "only when it accesses a corrupted page. See B<sigaction>(2) for more "
2342 "information on the B<SIGBUS> signal. The policy is inherited by children. "
2343 "The remaining unused B<prctl>() arguments must be zero for future "
2348 #: build/C/man2/prctl.2:660
2350 msgid "B<PR_MCE_KILL_GET> (since Linux 2.6.32)"
2354 #: build/C/man2/prctl.2:666
2356 "Return the current per-process machine check kill policy. All unused "
2357 "B<prctl>() arguments must be zero."
2361 #: build/C/man2/prctl.2:666
2363 msgid "B<PR_SET_MM> (since Linux 3.3)"
2366 #. commit 028ee4be34a09a6d48bdf30ab991ae933a7bc036
2368 #: build/C/man2/prctl.2:687
2370 "Modify certain kernel memory map descriptor fields of the calling process. "
2371 "Usually these fields are set by the kernel and dynamic loader (see "
2372 "B<ld.so>(8) for more information) and a regular application should not use "
2373 "this feature. However, there are cases, such as self-modifying programs, "
2374 "where a program might find it useful to change its own memory map. This "
2375 "feature is available only if the kernel is built with the "
2376 "B<CONFIG_CHECKPOINT_RESTORE> option enabled. The calling process must have "
2377 "the B<CAP_SYS_RESOURCE> capability. The value in I<arg2> is one of the "
2378 "options below, while I<arg3> provides a new value for the option."
2382 #: build/C/man2/prctl.2:688
2384 msgid "B<PR_SET_MM_START_CODE>"
2388 #: build/C/man2/prctl.2:697
2390 "Set the address above which the program text can run. The corresponding "
2391 "memory area must be readable and executable, but not writable or sharable "
2392 "(see B<mprotect>(2) and B<mmap>(2) for more information)."
2396 #: build/C/man2/prctl.2:697
2398 msgid "B<PR_SET_MM_END_CODE>"
2402 #: build/C/man2/prctl.2:702
2404 "Set the address below which the program text can run. The corresponding "
2405 "memory area must be readable and executable, but not writable or sharable."
2409 #: build/C/man2/prctl.2:702
2411 msgid "B<PR_SET_MM_START_DATA>"
2415 #: build/C/man2/prctl.2:708
2417 "Set the address above which initialized and uninitialized (bss) data are "
2418 "placed. The corresponding memory area must be readable and writable, but "
2419 "not executable or sharable."
2423 #: build/C/man2/prctl.2:708
2425 msgid "B<PR_SET_MM_END_DATA>"
2429 #: build/C/man2/prctl.2:714
2431 "Set the address below which initialized and uninitialized (bss) data are "
2432 "placed. The corresponding memory area must be readable and writable, but "
2433 "not executable or sharable."
2437 #: build/C/man2/prctl.2:714
2439 msgid "B<PR_SET_MM_START_STACK>"
2443 #: build/C/man2/prctl.2:718
2445 "Set the start address of the stack. The corresponding memory area must be "
2446 "readable and writable."
2450 #: build/C/man2/prctl.2:718
2452 msgid "B<PR_SET_MM_START_BRK>"
2456 #: build/C/man2/prctl.2:730
2458 "Set the address above which the program heap can be expanded with B<brk>(2) "
2459 "call. The address must be greater than the ending address of the current "
2460 "program data segment. In addition, the combined size of the resulting heap "
2461 "and the size of the data segment can't exceed the B<RLIMIT_DATA> resource "
2462 "limit (see B<setrlimit>(2))."
2466 #: build/C/man2/prctl.2:730
2468 msgid "B<PR_SET_MM_BRK>"
2472 #: build/C/man2/prctl.2:738
2474 "Set the current B<brk>(2) value. The requirements for the address are the "
2475 "same as for the B<PR_SET_MM_START_BRK> option."
2478 #. commit fe8c7f5cbf91124987106faa3bdf0c8b955c4cf7
2480 #: build/C/man2/prctl.2:741
2481 msgid "The following options are available since Linux 3.5."
2485 #: build/C/man2/prctl.2:741
2487 msgid "B<PR_SET_MM_ARG_START>"
2491 #: build/C/man2/prctl.2:744
2492 msgid "Set the address above which the program command line is placed."
2496 #: build/C/man2/prctl.2:744
2498 msgid "B<PR_SET_MM_ARG_END>"
2502 #: build/C/man2/prctl.2:747
2503 msgid "Set the address below which the program command line is placed."
2507 #: build/C/man2/prctl.2:747
2509 msgid "B<PR_SET_MM_ENV_START>"
2513 #: build/C/man2/prctl.2:750
2514 msgid "Set the address above which the program environment is placed."
2518 #: build/C/man2/prctl.2:750
2520 msgid "B<PR_SET_MM_ENV_END>"
2524 #: build/C/man2/prctl.2:753
2525 msgid "Set the address below which the program environment is placed."
2529 #: build/C/man2/prctl.2:766
2531 "The address passed with B<PR_SET_MM_ARG_START>, B<PR_SET_MM_ARG_END>, "
2532 "B<PR_SET_MM_ENV_START>, and B<PR_SET_MM_ENV_END> should belong to a process "
2533 "stack area. Thus, the corresponding memory area must be readable, writable, "
2534 "and (depending on the kernel configuration) have the B<MAP_GROWSDOWN> "
2535 "attribute set (see B<mmap>(2))."
2539 #: build/C/man2/prctl.2:766
2541 msgid "B<PR_SET_MM_AUXV>"
2545 #: build/C/man2/prctl.2:775
2547 "Set a new auxiliary vector. The I<arg3> argument should provide the address "
2548 "of the vector. The I<arg4> is the size of the vector."
2552 #: build/C/man2/prctl.2:775
2554 msgid "B<PR_SET_MM_EXE_FILE>"
2557 #. commit b32dfe377102ce668775f8b6b1461f7ad428f8b6
2559 #: build/C/man2/prctl.2:787
2561 "Supersede the I</proc/pid/exe> symbolic link with a new one pointing to a "
2562 "new executable file identified by the file descriptor provided in I<arg3> "
2563 "argument. The file descriptor should be obtained with a regular B<open>(2) "
2568 #: build/C/man2/prctl.2:794
2570 "To change the symbolic link, one needs to unmap all existing executable "
2571 "memory areas, including those created by the kernel itself (for example the "
2572 "kernel usually creates at least one executable memory area for the ELF "
2573 "I<.text> section)."
2577 #: build/C/man2/prctl.2:800
2579 "The second limitation is that such transitions can be done only once in a "
2580 "process life time. Any further attempts will be rejected. This should help "
2581 "system administrators monitor unusual symbolic-link transitions over all "
2582 "processes running on a system."
2586 #: build/C/man2/prctl.2:822
2588 "On success, B<PR_GET_DUMPABLE>, B<PR_GET_KEEPCAPS>, B<PR_GET_NO_NEW_PRIVS>, "
2589 "B<PR_GET_THP_DISABLE>, B<PR_CAPBSET_READ>, B<PR_GET_TIMING>, "
2590 "B<PR_GET_TIMERSLACK>, B<PR_GET_SECUREBITS>, B<PR_MCE_KILL_GET>, and (if it "
2591 "returns) B<PR_GET_SECCOMP> return the nonnegative values described above. "
2592 "All other I<option> values return 0 on success. On error, -1 is returned, "
2593 "and I<errno> is set appropriately."
2597 #: build/C/man2/prctl.2:827
2598 msgid "I<arg2> is an invalid address."
2602 #: build/C/man2/prctl.2:832
2603 msgid "The value of I<option> is not recognized."
2607 #: build/C/man2/prctl.2:844
2609 "I<option> is B<PR_MCE_KILL> or B<PR_MCE_KILL_GET> or B<PR_SET_MM>, and "
2610 "unused B<prctl>() arguments were not specified as zero."
2614 #: build/C/man2/prctl.2:849
2615 msgid "I<arg2> is not valid value for this I<option>."
2619 #: build/C/man2/prctl.2:858
2621 "I<option> is B<PR_SET_SECCOMP> or B<PR_GET_SECCOMP>, and the kernel was not "
2622 "configured with B<CONFIG_SECCOMP>."
2626 #: build/C/man2/prctl.2:864
2627 msgid "I<option> is B<PR_SET_MM>, and one of the following is true"
2631 #: build/C/man2/prctl.2:870
2632 msgid "I<arg4> or I<arg5> is nonzero;"
2636 #: build/C/man2/prctl.2:875
2638 "I<arg3> is greater than B<TASK_SIZE> (the limit on the size of the user "
2639 "address space for this architecture);"
2643 #: build/C/man2/prctl.2:885
2645 "I<arg2> is B<PR_SET_MM_START_CODE>, B<PR_SET_MM_END_CODE>, "
2646 "B<PR_SET_MM_START_DATA>, B<PR_SET_MM_END_DATA>, or B<PR_SET_MM_START_STACK>, "
2647 "and the permissions of the corresponding memory area are not as required;"
2651 #: build/C/man2/prctl.2:897
2653 "I<arg2> is B<PR_SET_MM_START_BRK> or B<PR_SET_MM_BRK>, and I<arg3> is less "
2654 "than or equal to the end of the data segment or specifies a value that would "
2655 "cause the B<RLIMIT_DATA> resource limit to be exceeded."
2659 #: build/C/man2/prctl.2:908
2661 "I<option> is B<PR_SET_PTRACER> and I<arg2> is not 0, B<PR_SET_PTRACER_ANY>, "
2662 "or the PID of an existing process."
2666 #: build/C/man2/prctl.2:916
2667 msgid "I<option> is B<PR_SET_PDEATHSIG> and I<arg2> is not a valid signal number."
2671 #: build/C/man2/prctl.2:927
2673 "I<option> is B<PR_SET_DUMPABLE> and I<arg2> is neither B<SUID_DUMP_DISABLE> "
2674 "nor B<SUID_DUMP_USER>."
2678 #: build/C/man2/prctl.2:936
2679 msgid "I<option> is B<PR_SET_TIMING> and I<arg2> is not B<PR_TIMING_STATISTICAL>."
2683 #: build/C/man2/prctl.2:950
2685 "I<option> is B<PR_SET_NO_NEW_PRIVS> and I<arg2> is not equal to 1 or "
2686 "I<arg3>, I<arg4>, or I<arg5> is nonzero."
2690 #: build/C/man2/prctl.2:962
2692 "I<option> is B<PR_GET_NO_NEW_PRIVS> and I<arg2>, I<arg3>, I<arg4>, or "
2693 "I<arg5> is nonzero."
2697 #: build/C/man2/prctl.2:973
2699 "I<option> is B<PR_SET_THP_DISABLE> and I<arg3>, I<arg4>, or I<arg5> is "
2704 #: build/C/man2/prctl.2:985
2706 "I<option> is B<PR_GET_THP_DISABLE> and I<arg2>, I<arg3>, I<arg4>, or I<arg5> "
2711 #: build/C/man2/prctl.2:997
2713 "I<option> is B<PR_SET_SECUREBITS>, and the caller does not have the "
2714 "B<CAP_SETPCAP> capability, or tried to unset a \"locked\" flag, or tried to "
2715 "set a flag whose corresponding locked flag was set (see B<capabilities>(7))."
2719 #: build/C/man2/prctl.2:1007
2721 "I<option> is B<PR_SET_KEEPCAPS>, and the callers's "
2722 "B<SECURE_KEEP_CAPS_LOCKED> flag is set (see B<capabilities>(7))."
2726 #: build/C/man2/prctl.2:1015
2728 "I<option> is B<PR_CAPBSET_DROP>, and the caller does not have the "
2729 "B<CAP_SETPCAP> capability."
2733 #: build/C/man2/prctl.2:1023
2735 "I<option> is B<PR_SET_MM>, and the caller does not have the "
2736 "B<CAP_SYS_RESOURCE> capability."
2740 #: build/C/man2/prctl.2:1023
2746 #: build/C/man2/prctl.2:1033
2748 "I<option> is B<PR_SET_MM>, and I<arg3> is B<PR_SET_MM_EXE_FILE>, the file is "
2753 #: build/C/man2/prctl.2:1033
2759 #: build/C/man2/prctl.2:1044
2761 "I<option> is B<PR_SET_MM>, I<arg3> is B<PR_SET_MM_EXE_FILE>, and this the "
2762 "second attempt to change the I</proc/pid/exe> symbolic link, which is "
2767 #: build/C/man2/prctl.2:1044 build/C/man2/signalfd.2:266 build/C/man2/timerfd_create.2:338
2772 #. The following can't actually happen, because prctl() in
2773 #. seccomp mode will cause SIGKILL.
2778 #. .BR PR_SET_SECCOMP ,
2779 #. and secure computing mode is already 1.
2781 #: build/C/man2/prctl.2:1063
2783 "I<option> is B<PR_SET_MM>, I<arg3> is B<PR_SET_MM_EXE_FILE>, and the file "
2784 "descriptor passed in I<arg4> is not valid."
2787 #. The library interface was added in glibc 2.0.6
2789 #: build/C/man2/prctl.2:1068
2790 msgid "The B<prctl>() system call was introduced in Linux 2.1.57."
2794 #: build/C/man2/prctl.2:1075
2796 "This call is Linux-specific. IRIX has a B<prctl>() system call (also "
2797 "introduced in Linux 2.1.44 as irix_prctl on the MIPS architecture), with "
2802 #: build/C/man2/prctl.2:1077
2803 msgid "B<ptrdiff_t prctl(int >I<option>B<, int >I<arg2>B<, int >I<arg3>B<);>"
2807 #: build/C/man2/prctl.2:1082
2809 "and options to get the maximum number of processes per user, get the maximum "
2810 "number of processors the calling process can use, find out whether a "
2811 "specified process is currently blocked, get or set the maximum stack size, "
2816 #: build/C/man2/prctl.2:1085
2817 msgid "B<signal>(2), B<core>(5)"
2821 #: build/C/man3/profil.3:28
2827 #: build/C/man3/profil.3:31
2828 msgid "profil - execution time profile"
2832 #: build/C/man3/profil.3:34
2834 msgid "B<#include E<lt>unistd.hE<gt>>\n"
2838 #: build/C/man3/profil.3:37
2841 "B<int profil(unsigned short *>I<buf>B<, size_t >I<bufsiz>B<,>\n"
2842 "B< size_t >I<offset>B<, unsigned int >I<scale>B<);>\n"
2846 #: build/C/man3/profil.3:46
2847 msgid "B<profil>(): _BSD_SOURCE || (_XOPEN_SOURCE && _XOPEN_SOURCE\\ E<lt>\\ 500)"
2851 #: build/C/man3/profil.3:68
2853 "This routine provides a means to find out in what areas your program spends "
2854 "most of its time. The argument I<buf> points to I<bufsiz> bytes of core. "
2855 "Every virtual 10 milliseconds, the user's program counter (PC) is examined: "
2856 "I<offset> is subtracted and the result is multiplied by I<scale> and divided "
2857 "by 65536. If the resulting value is less than I<bufsiz>, then the "
2858 "corresponding entry in I<buf> is incremented. If I<buf> is NULL, profiling "
2863 #: build/C/man3/profil.3:70
2864 msgid "Zero is always returned."
2868 #: build/C/man3/profil.3:72
2869 msgid "Similar to a call in SVr4 (but not POSIX.1-2001)."
2873 #: build/C/man3/profil.3:78
2875 "B<profil>() cannot be used on a program that also uses B<ITIMER_PROF> "
2876 "interval timers (see B<setitimer>(2))."
2880 #: build/C/man3/profil.3:81
2882 "True kernel profiling provides more accurate results. Libc 4.4 contained a "
2883 "kernel patch providing a system call profil."
2887 #: build/C/man3/profil.3:86
2888 msgid "B<gprof>(1), B<setitimer>(2), B<sigaction>(2), B<signal>(2)"
2892 #: build/C/man3/psignal.3:30
2898 #: build/C/man3/psignal.3:30
2904 #: build/C/man3/psignal.3:30 build/C/man3/raise.3:29 build/C/man7/sigevent.7:26
2910 #: build/C/man3/psignal.3:33
2911 msgid "psignal, psiginfo - print signal message"
2915 #: build/C/man3/psignal.3:39
2918 "B<void psignal(int >I<sig>B<, const char *>I<s>B<);>\n"
2919 "B<void psiginfo(const siginfo_t *>I<pinfo>B<, const char *>I<s>B<);>\n"
2923 #: build/C/man3/psignal.3:41
2925 msgid "B<extern const char *const >I<sys_siglist>B<[];>\n"
2929 #: build/C/man3/psignal.3:50
2930 msgid "B<psignal>(): _SVID_SOURCE || _BSD_SOURCE"
2934 #: build/C/man3/psignal.3:53
2936 "B<psiginfo>(): _XOPEN_SOURCE\\ E<gt>=\\ 700 || _POSIX_C_SOURCE\\ E<gt>=\\ "
2941 #: build/C/man3/psignal.3:56
2942 msgid "I<sys_siglist>: _BSD_SOURCE"
2946 #: build/C/man3/psignal.3:65
2948 "The B<psignal>() function displays a message on I<stderr> consisting of the "
2949 "string I<s>, a colon, a space, a string describing the signal number I<sig>, "
2950 "and a trailing newline. If the string I<s> is NULL or empty, the colon and "
2951 "space are omitted. If I<sig> is invalid, the message displayed will "
2952 "indicate an unknown signal."
2956 #: build/C/man3/psignal.3:86
2958 "The B<psiginfo>() function is like B<psignal>(), except that it displays "
2959 "information about the signal described by I<pinfo>, which should point to a "
2960 "valid I<siginfo_t> structure. As well as the signal description, "
2961 "B<psiginfo>() displays information about the origin of the signal, and "
2962 "other information relevant to the signal (e.g., the relevant memory address "
2963 "for hardware-generated signals, the child process ID for B<SIGCHLD>, and the "
2964 "user ID and process ID of the sender, for signals set using B<kill>(2) or "
2969 #: build/C/man3/psignal.3:89
2971 "The array I<sys_siglist> holds the signal description strings indexed by "
2976 #: build/C/man3/psignal.3:95
2977 msgid "The B<psignal>() and B<psiginfo>() functions return no value."
2981 #: build/C/man3/psignal.3:99
2982 msgid "The B<psiginfo>() function was added to glibc in version 2.10."
2986 #: build/C/man3/psignal.3:101
2987 msgid "POSIX.1-2008, 4.3BSD."
2991 #: build/C/man3/psignal.3:105
2992 msgid "In glibc versions up to 2.12, B<psiginfo>() had the following bugs:"
2995 #. FIXME http://sourceware.org/bugzilla/show_bug.cgi?id=12107
2996 #. Reportedly now fixed; check glibc 2.13
2998 #: build/C/man3/psignal.3:109
2999 msgid "In some circumstances, a trailing newline is not printed."
3002 #. FIXME http://sourceware.org/bugzilla/show_bug.cgi?id=12108
3003 #. Reportedly now fixed; check glibc 2.13
3005 #: build/C/man3/psignal.3:113
3006 msgid "Additional details are not displayed for real-time signals."
3010 #: build/C/man3/psignal.3:118
3011 msgid "B<sigaction>(2), B<perror>(3), B<strsignal>(3), B<signal>(7)"
3015 #: build/C/man3/raise.3:29
3021 #: build/C/man3/raise.3:29
3027 #: build/C/man3/raise.3:32
3028 msgid "raise - send a signal to the caller"
3032 #: build/C/man3/raise.3:37
3034 msgid "B<int raise(int >I<sig>B<);>\n"
3038 #: build/C/man3/raise.3:43
3040 "The B<raise>() function sends a signal to the calling process or thread. "
3041 "In a single-threaded program it is equivalent to"
3045 #: build/C/man3/raise.3:47
3047 msgid "kill(getpid(), sig);\n"
3051 #: build/C/man3/raise.3:51
3052 msgid "In a multithreaded program it is equivalent to"
3056 #: build/C/man3/raise.3:55
3058 msgid "pthread_kill(pthread_self(), sig);\n"
3062 #: build/C/man3/raise.3:61
3064 "If the signal causes a handler to be called, B<raise>() will return only "
3065 "after the signal handler has returned."
3069 #: build/C/man3/raise.3:64
3070 msgid "B<raise>() returns 0 on success, and nonzero for failure."
3074 #: build/C/man3/raise.3:69
3075 msgid "The B<raise>() function is thread-safe."
3079 #: build/C/man3/raise.3:71 build/C/man2/signal.2:112
3080 msgid "C89, C99, POSIX.1-2001."
3083 #. 2.3.2 used the obsolete tkill(), if available.
3085 #: build/C/man3/raise.3:82
3087 "Since version 2.3.3, glibc implements B<raise>() by calling B<tgkill>(2), "
3088 "if the kernel supports that system call. Older glibc versions implemented "
3089 "B<raise>() using B<kill>(2)."
3093 #: build/C/man3/raise.3:89
3095 "B<getpid>(2), B<kill>(2), B<sigaction>(2), B<signal>(2), B<pthread_kill>(3), "
3100 #: build/C/man2/restart_syscall.2:33
3102 msgid "RESTART_SYSCALL"
3106 #: build/C/man2/restart_syscall.2:33
3112 #: build/C/man2/restart_syscall.2:36
3113 msgid "restart_syscall - restart a system call after interruption by a stop signal"
3117 #: build/C/man2/restart_syscall.2:38
3118 msgid "B<int restart_syscall(void);>"
3122 #: build/C/man2/restart_syscall.2:41
3123 msgid "I<Note>: There is no glibc wrapper for this system call; see NOTES."
3127 #: build/C/man2/restart_syscall.2:53
3129 "The B<restart_syscall>() system call is used to restart certain system "
3130 "calls after a process that was stopped by a signal (e.g., B<SIGSTOP> or "
3131 "B<SIGTSTP>) is later resumed after receiving a B<SIGCONT> signal. This "
3132 "system call is designed only for internal use by the kernel."
3135 #. These system calls correspond to the special internal errno value
3136 #. ERESTART_RESTARTBLOCK. Each of the system calls has a "restart"
3137 #. helper function that is invoked by restart_syscall().
3139 #: build/C/man2/restart_syscall.2:84
3141 "B<restart_syscall>() is used for restarting only those system calls that, "
3142 "when restarted, should adjust their time-related parameters\\(emnamely "
3143 "B<poll>(2) (since Linux 2.6.24), B<nanosleep>(2) (since Linux 2.6), "
3144 "B<clock_nanosleep>(2) (since Linux 2.6), and B<futex>(2), when employed "
3145 "with the B<FUTEX_WAIT> (since Linux 2.6.22) and B<FUTEX_WAIT_BITSET> (since "
3146 "Linux 2.6.31) operations. B<restart_syscall>() restarts the interrupted "
3147 "system call with a time argument that is suitably adjusted to account for "
3148 "the time that has already elapsed (including the time where the process was "
3149 "stopped by a signal). Without the B<restart_syscall>() mechanism, "
3150 "restarting these system calls would not correctly deduce the already elapsed "
3151 "time when the process continued execution."
3155 #: build/C/man2/restart_syscall.2:88
3157 "The return value of B<restart_syscall>() is the return value of whatever "
3158 "system call is being restarted."
3162 #: build/C/man2/restart_syscall.2:92
3164 "I<errno> is set as per the errors for whatever system call is being "
3165 "restarted by B<restart_syscall>()."
3169 #: build/C/man2/restart_syscall.2:96
3170 msgid "The B<restart_syscall>() system call is present since Linux 2.6."
3174 #: build/C/man2/restart_syscall.2:98
3175 msgid "This system call is Linux-specific."
3179 #: build/C/man2/restart_syscall.2:102
3181 "There is no glibc wrapper for this system call, because it is intended for "
3182 "use only by the kernel and should never be called by applications."
3187 #. There is one oddness in the implementation though, with respect to
3188 #. nanosleep() (and probably also clock_nanosleep()). The scenario
3190 #. 1. Start a nanosleep() for (say) 30 seconds,
3191 #. 2. Stop the process with (say) SIGTSTP (^Z).
3192 #. 3. Resume the process with SIGCONT,
3193 #. 4. Upon return, the 'rem' argument of nanosleep() will contain the
3194 #. remaining unslept time **at the time when SIGTSTP was delivered**.
3195 #. The behavior at point 4 is odd, but doesn't violate the standards, which
3196 #. specify the treatment of 'rem' only when the system call returns with
3197 #. the error EINTR (i.e., the call was interrupted by a signal handler).
3199 #: build/C/man2/restart_syscall.2:123
3201 "From user space, the operation of B<restart_syscall>(2) is largely "
3202 "invisible: to the process that made the system call that is restarted, it "
3203 "appears as though that system call executed and returned in the usual "
3207 #. FIXME select(2) should probably get the restart_syscall() treatment:
3208 #. If a select() call is suspended by stop-sig+SIGCONT, the time
3209 #. spent suspended is *not* deducted when the select() is restarted.
3210 #. FIXME: check whether recvmmsg() handles stop-sig+SIGCONT properly.
3212 #: build/C/man2/restart_syscall.2:131
3213 msgid "B<sigaction>(2), B<sigreturn>(2), B<signal>(7)"
3217 #: build/C/man2/rt_sigqueueinfo.2:25
3219 msgid "RT_SIGQUEUEINFO"
3223 #: build/C/man2/rt_sigqueueinfo.2:25 build/C/man2/tkill.2:29
3229 #: build/C/man2/rt_sigqueueinfo.2:28
3230 msgid "rt_sigqueueinfo, rt_tgsigqueueinfo - queue a signal and data"
3234 #: build/C/man2/rt_sigqueueinfo.2:31
3237 "B<int rt_sigqueueinfo(pid_t >I<tgid>B<, int >I<sig>B<, siginfo_t "
3242 #: build/C/man2/rt_sigqueueinfo.2:34
3245 "B<int rt_tgsigqueueinfo(pid_t >I<tgid>B<, pid_t >I<tid>B<, int >I<sig>B<,>\n"
3246 "B< siginfo_t *>I<uinfo>B<);>\n"
3250 #: build/C/man2/rt_sigqueueinfo.2:38 build/C/man2/sgetmask.2:36 build/C/man2/tkill.2:41
3251 msgid "I<Note>: There are no glibc wrappers for these system calls; see NOTES."
3255 #: build/C/man2/rt_sigqueueinfo.2:50
3257 "The B<rt_sigqueueinfo>() and B<rt_tgsigqueueinfo>() system calls are the "
3258 "low-level interfaces used to send a signal plus data to a process or "
3259 "thread. The receiver of the signal can obtain the accompanying data by "
3260 "establishing a signal handler with the B<sigaction>(2) B<SA_SIGINFO> flag."
3264 #: build/C/man2/rt_sigqueueinfo.2:56
3266 "These system calls are not intended for direct application use; they are "
3267 "provided to allow the implementation of B<sigqueue>(3) and "
3268 "B<pthread_sigqueue>(3)."
3272 #: build/C/man2/rt_sigqueueinfo.2:68
3274 "The B<rt_sigqueueinfo>() system call sends the signal I<sig> to the thread "
3275 "group with the ID I<tgid>. (The term \"thread group\" is synonymous with "
3276 "\"process\", and I<tid> corresponds to the traditional UNIX process ID.) "
3277 "The signal will be delivered to an arbitrary member of the thread group "
3278 "(i.e., one of the threads that is not currently blocking the signal)."
3282 #: build/C/man2/rt_sigqueueinfo.2:79
3284 "The I<uinfo> argument specifies the data to accompany the signal. This "
3285 "argument is a pointer to a structure of type I<siginfo_t>, described in "
3286 "B<sigaction>(2) (and defined by including I<E<lt>sigaction.hE<gt>>). The "
3287 "caller should set the following fields in this structure:"
3291 #: build/C/man2/rt_sigqueueinfo.2:79 build/C/man7/sigevent.7:88 build/C/man2/wait.2:316
3298 #: build/C/man2/rt_sigqueueinfo.2:95
3300 "This must be one of the B<SI_*> codes in the Linux kernel source file "
3301 "I<include/asm-generic/siginfo.h>, with the restriction that the code must be "
3302 "negative (i.e., cannot be B<SI_USER>, which is used by the kernel to "
3303 "indicate a signal sent by B<kill>(2)) and cannot (since Linux 2.6.39) be "
3304 "B<SI_TKILL> (which is used by the kernel to indicate a signal sent using "
3309 #: build/C/man2/rt_sigqueueinfo.2:95 build/C/man2/wait.2:295
3315 #: build/C/man2/rt_sigqueueinfo.2:99
3316 msgid "This should be set to a process ID, typically the process ID of the sender."
3320 #: build/C/man2/rt_sigqueueinfo.2:99 build/C/man2/wait.2:298
3326 #: build/C/man2/rt_sigqueueinfo.2:103
3327 msgid "This should be set to a user ID, typically the real user ID of the sender."
3331 #: build/C/man2/rt_sigqueueinfo.2:103 build/C/man7/sigevent.7:96
3337 #: build/C/man2/rt_sigqueueinfo.2:110
3339 "This field contains the user data to accompany the signal. For more "
3340 "information, see the description of the last (I<union sigval>) argument of "
3345 #: build/C/man2/rt_sigqueueinfo.2:117
3347 "Internally, the kernel sets the I<si_signo> field to the value specified in "
3348 "I<sig>, so that the receiver of the signal can also obtain the signal number "
3353 #: build/C/man2/rt_sigqueueinfo.2:129
3355 "The B<rt_tgsigqueueinfo>() system call is like B<rt_sigqueueinfo>(), but "
3356 "sends the signal and data to the single thread specified by the combination "
3357 "of I<tgid>, a thread group ID, and I<tid>, a thread in that thread group."
3361 #: build/C/man2/rt_sigqueueinfo.2:134
3363 "On success, these system calls return 0. On error, they return -1 and "
3364 "I<errno> is set to indicate the error."
3368 #: build/C/man2/rt_sigqueueinfo.2:135 build/C/man3/sigqueue.3:92 build/C/man2/sigwaitinfo.2:115 build/C/man2/timer_create.2:176
3374 #: build/C/man2/rt_sigqueueinfo.2:141 build/C/man3/sigqueue.3:98
3376 "The limit of signals which may be queued has been reached. (See "
3377 "B<signal>(7) for further information.)"
3381 #: build/C/man2/rt_sigqueueinfo.2:148
3382 msgid "I<sig>, I<tgid>, or I<tid> was invalid."
3386 #: build/C/man2/rt_sigqueueinfo.2:156
3388 "The caller does not have permission to send the signal to the target. For "
3389 "the required permissions, see B<kill>(2). Or: I<uinfo-E<gt>si_code> is "
3394 #: build/C/man2/rt_sigqueueinfo.2:162
3395 msgid "B<rt_sigqueueinfo>(): No thread group matching I<tgid> was found."
3399 #: build/C/man2/rt_sigqueueinfo.2:169
3400 msgid "B<rt_tgsigqueinfo>(): No thread matching I<tgid> and I<tid> was found."
3404 #: build/C/man2/rt_sigqueueinfo.2:176
3406 "The B<rt_sigqueueinfo>() system call was added to Linux in version 2.2. "
3407 "The B<rt_tgsigqueueinfo>() system call was added to Linux in version "
3412 #: build/C/man2/rt_sigqueueinfo.2:178 build/C/man2/sgetmask.2:68 build/C/man2/timerfd_create.2:373
3413 msgid "These system calls are Linux-specific."
3417 #: build/C/man2/rt_sigqueueinfo.2:183
3419 "Since these system calls are not intended for application use, there are no "
3420 "glibc wrapper functions; use B<syscall>(2) in the unlikely case that you "
3421 "want to call them directly."
3425 #: build/C/man2/rt_sigqueueinfo.2:188
3427 "As with B<kill>(2), the null signal (0) can be used to check if the "
3428 "specified process or thread exists."
3432 #: build/C/man2/rt_sigqueueinfo.2:196
3434 "B<kill>(2), B<sigaction>(2), B<sigprocmask>(2), B<tgkill>(2), "
3435 "B<pthread_sigqueue>(3), B<sigqueue>(3), B<signal>(7)"
3439 #: build/C/man2/s390_runtime_instr.2:25
3441 msgid "S390_RUNTIME_INSTR"
3445 #: build/C/man2/s390_runtime_instr.2:25
3451 #: build/C/man2/s390_runtime_instr.2:28
3452 msgid "s390_runtime_instr - enable/disable s390 CPU run-time instrumentation"
3456 #: build/C/man2/s390_runtime_instr.2:31
3458 msgid "B<#include E<lt>asm/runtime_instr.hE<gt>>\n"
3462 #: build/C/man2/s390_runtime_instr.2:33
3464 msgid "B<int s390_runtime_instr(int >I<command>B<, int >I<signum>B<);>\n"
3468 #: build/C/man2/s390_runtime_instr.2:39
3470 "The B<s390_runtime_instr>() system call starts or stops CPU run-time "
3471 "instrumentation for the calling thread."
3475 #: build/C/man2/s390_runtime_instr.2:47
3477 "The I<command> argument controls whether run-time instrumentation is started "
3478 "(B<S390_RUNTIME_INSTR_START>, 1) or stopped (B<S390_RUNTIME_INSTR_STOP>, 2) "
3479 "for the calling thread."
3483 #: build/C/man2/s390_runtime_instr.2:54
3485 "The I<signum> argument specifies the number of a real-time signal. The "
3486 "real-time signal is sent to the thread if the run-time instrumentation "
3487 "buffer is full or if the run-time-instrumentation-halted interrupt occurred."
3491 #: build/C/man2/s390_runtime_instr.2:65
3493 "On success, B<s390_runtime_instr>() returns 0 and enables the thread for "
3494 "run-time instrumentation by assigning the thread a default run-time "
3495 "instrumentation control block. The caller can then read and modify the "
3496 "control block and start the run-time instrumentation. On error, -1 is "
3497 "returned and I<errno> is set to one of the error codes listed below."
3501 #: build/C/man2/s390_runtime_instr.2:73
3503 "The value specified in I<command> is not a valid command or the value "
3504 "specified in I<signum> is not a real-time signal number."
3508 #: build/C/man2/s390_runtime_instr.2:76
3509 msgid "Allocating memory for the run-time instrumentation control block failed."
3513 #: build/C/man2/s390_runtime_instr.2:76
3515 msgid "B<EOPNOTSUPP>"
3519 #: build/C/man2/s390_runtime_instr.2:79
3520 msgid "The run-time instrumentation facility is not available."
3524 #: build/C/man2/s390_runtime_instr.2:81
3525 msgid "This system call is available since Linux 3.7."
3529 #: build/C/man2/s390_runtime_instr.2:84
3531 "This Linux-specific system call is available only on the s390 architecture. "
3532 "The run-time instrumentation facility is available beginning with System z "
3537 #: build/C/man2/s390_runtime_instr.2:88
3539 "Glibc does not provide a wrapper for this system call, use B<syscall>(2) to "
3544 #: build/C/man2/s390_runtime_instr.2:91
3545 msgid "B<syscall>(2), B<signal>(7)"
3549 #: build/C/man2/sgetmask.2:26
3555 #: build/C/man2/sgetmask.2:26
3561 #: build/C/man2/sgetmask.2:29
3562 msgid "sgetmask, ssetmask - manipulation of signal mask (obsolete)"
3566 #: build/C/man2/sgetmask.2:31
3567 msgid "B<long sgetmask(void);>"
3571 #: build/C/man2/sgetmask.2:33
3572 msgid "B<long ssetmask(long >I<newmask>B<);>"
3576 #: build/C/man2/sgetmask.2:42
3578 "These system calls are obsolete. I<Do not use them>; use B<sigprocmask>(2) "
3583 #: build/C/man2/sgetmask.2:45
3584 msgid "B<sgetmask>() returns the signal mask of the calling process."
3588 #: build/C/man2/sgetmask.2:50
3590 "B<ssetmask>() sets the signal mask of the calling process to the value "
3591 "given in I<newmask>. The previous signal mask is returned."
3595 #: build/C/man2/sgetmask.2:59
3597 "The signal masks dealt with by these two system calls are plain bit masks "
3598 "(unlike the I<sigset_t> used by B<sigprocmask>(2)); use B<sigmask>(3) to "
3599 "create and inspect these masks."
3603 #: build/C/man2/sgetmask.2:64
3605 "B<sgetmask>() always successfully returns the signal mask. B<ssetmask>() "
3606 "always succeeds, and returns the previous signal mask."
3610 #: build/C/man2/sgetmask.2:66
3611 msgid "These system calls always succeed."
3615 #: build/C/man2/sgetmask.2:72
3617 "Glibc does not provide wrappers for these obsolete system calls; in the "
3618 "unlikely event that you want to call them, use B<syscall>(2)."
3622 #: build/C/man2/sgetmask.2:75
3624 "These system calls are unaware of signal numbers greater than 31 (i.e., "
3625 "real-time signals)."
3629 #: build/C/man2/sgetmask.2:77
3630 msgid "These system calls do not exist on x86-64."
3634 #: build/C/man2/sgetmask.2:82
3635 msgid "It is not possible to block B<SIGSTOP> or B<SIGKILL>."
3639 #: build/C/man2/sgetmask.2:85
3640 msgid "B<sigprocmask>(2), B<signal>(7)"
3644 #: build/C/man2/sigaction.2:47
3650 #: build/C/man2/sigaction.2:47
3656 #: build/C/man2/sigaction.2:50
3657 msgid "sigaction - examine and change a signal action"
3661 #: build/C/man2/sigaction.2:56
3664 "B<int sigaction(int >I<signum>B<, const struct sigaction *>I<act>B<,>\n"
3665 "B< struct sigaction *>I<oldact>B<);>\n"
3669 #: build/C/man2/sigaction.2:66
3671 "B<sigaction>(): _POSIX_C_SOURCE\\ E<gt>=\\ 1 || _XOPEN_SOURCE || "
3676 #: build/C/man2/sigaction.2:69
3677 msgid "I<siginfo_t>: _POSIX_C_SOURCE E<gt>= 199309L"
3681 #: build/C/man2/sigaction.2:78
3683 "The B<sigaction>() system call is used to change the action taken by a "
3684 "process on receipt of a specific signal. (See B<signal>(7) for an overview "
3689 #: build/C/man2/sigaction.2:84
3691 "I<signum> specifies the signal and can be any valid signal except B<SIGKILL> "
3696 #: build/C/man2/sigaction.2:95
3698 "If I<act> is non-NULL, the new action for signal I<signum> is installed from "
3699 "I<act>. If I<oldact> is non-NULL, the previous action is saved in "
3704 #: build/C/man2/sigaction.2:99
3705 msgid "The I<sigaction> structure is defined as something like:"
3709 #: build/C/man2/sigaction.2:109
3712 "struct sigaction {\n"
3713 " void (*sa_handler)(int);\n"
3714 " void (*sa_sigaction)(int, siginfo_t *, void *);\n"
3715 " sigset_t sa_mask;\n"
3717 " void (*sa_restorer)(void);\n"
3722 #: build/C/man2/sigaction.2:116
3724 "On some architectures a union is involved: do not assign to both "
3725 "I<sa_handler> and I<sa_sigaction>."
3729 #: build/C/man2/sigaction.2:123
3731 "The I<sa_restorer> element is obsolete and should not be used. POSIX does "
3732 "not specify a I<sa_restorer> element."
3736 #: build/C/man2/sigaction.2:133
3738 "I<sa_handler> specifies the action to be associated with I<signum> and may "
3739 "be B<SIG_DFL> for the default action, B<SIG_IGN> to ignore this signal, or a "
3740 "pointer to a signal handling function. This function receives the signal "
3741 "number as its only argument."
3745 #: build/C/man2/sigaction.2:155
3747 "If B<SA_SIGINFO> is specified in I<sa_flags>, then I<sa_sigaction> (instead "
3748 "of I<sa_handler>) specifies the signal-handling function for I<signum>. "
3749 "This function receives the signal number as its first argument, a pointer to "
3750 "a I<siginfo_t> as its second argument and a pointer to a I<ucontext_t> (cast "
3751 "to I<void\\ *>) as its third argument. (Commonly, the handler function "
3752 "doesn't make any use of the third argument. See B<getcontext>(3) for "
3753 "further information about I<ucontext_t>.)"
3757 #: build/C/man2/sigaction.2:165
3759 "I<sa_mask> specifies a mask of signals which should be blocked (i.e., added "
3760 "to the signal mask of the thread in which the signal handler is invoked) "
3761 "during execution of the signal handler. In addition, the signal which "
3762 "triggered the handler will be blocked, unless the B<SA_NODEFER> flag is "
3767 #: build/C/man2/sigaction.2:169
3769 "I<sa_flags> specifies a set of flags which modify the behavior of the "
3770 "signal. It is formed by the bitwise OR of zero or more of the following:"
3774 #: build/C/man2/sigaction.2:170
3776 msgid "B<SA_NOCLDSTOP>"
3780 #: build/C/man2/sigaction.2:187
3782 "If I<signum> is B<SIGCHLD>, do not receive notification when child processes "
3783 "stop (i.e., when they receive one of B<SIGSTOP>, B<SIGTSTP>, B<SIGTTIN>, or "
3784 "B<SIGTTOU>) or resume (i.e., they receive B<SIGCONT>) (see B<wait>(2)). "
3785 "This flag is meaningful only when establishing a handler for B<SIGCHLD>."
3789 #: build/C/man2/sigaction.2:187
3791 msgid "B<SA_NOCLDWAIT> (since Linux 2.6)"
3794 #. To be precise: Linux 2.5.60 -- MTK
3796 #: build/C/man2/sigaction.2:201
3798 "If I<signum> is B<SIGCHLD>, do not transform children into zombies when they "
3799 "terminate. See also B<waitpid>(2). This flag is meaningful only when "
3800 "establishing a handler for B<SIGCHLD>, or when setting that signal's "
3801 "disposition to B<SIG_DFL>."
3805 #: build/C/man2/sigaction.2:213
3807 "If the B<SA_NOCLDWAIT> flag is set when establishing a handler for "
3808 "B<SIGCHLD>, POSIX.1 leaves it unspecified whether a B<SIGCHLD> signal is "
3809 "generated when a child process terminates. On Linux, a B<SIGCHLD> signal is "
3810 "generated in this case; on some other implementations, it is not."
3814 #: build/C/man2/sigaction.2:213
3816 msgid "B<SA_NODEFER>"
3820 #: build/C/man2/sigaction.2:220
3822 "Do not prevent the signal from being received from within its own signal "
3823 "handler. This flag is meaningful only when establishing a signal handler. "
3824 "B<SA_NOMASK> is an obsolete, nonstandard synonym for this flag."
3828 #: build/C/man2/sigaction.2:220
3830 msgid "B<SA_ONSTACK>"
3834 #: build/C/man2/sigaction.2:226
3836 "Call the signal handler on an alternate signal stack provided by "
3837 "B<sigaltstack>(2). If an alternate stack is not available, the default "
3838 "stack will be used. This flag is meaningful only when establishing a signal "
3843 #: build/C/man2/sigaction.2:226
3845 msgid "B<SA_RESETHAND>"
3849 #: build/C/man2/sigaction.2:232
3851 "Restore the signal action to the default upon entry to the signal handler. "
3852 "This flag is meaningful only when establishing a signal handler. "
3853 "B<SA_ONESHOT> is an obsolete, nonstandard synonym for this flag."
3857 #: build/C/man2/sigaction.2:232
3859 msgid "B<SA_RESTART>"
3863 #: build/C/man2/sigaction.2:240
3865 "Provide behavior compatible with BSD signal semantics by making certain "
3866 "system calls restartable across signals. This flag is meaningful only when "
3867 "establishing a signal handler. See B<signal>(7) for a discussion of system "
3872 #: build/C/man2/sigaction.2:240
3874 msgid "B<SA_SIGINFO> (since Linux 2.2)"
3879 #. field was added in Linux 2.1.86.)
3881 #: build/C/man2/sigaction.2:251
3883 "The signal handler takes three arguments, not one. In this case, "
3884 "I<sa_sigaction> should be set instead of I<sa_handler>. This flag is "
3885 "meaningful only when establishing a signal handler."
3889 #: build/C/man2/sigaction.2:258
3891 "The I<siginfo_t> argument to I<sa_sigaction> is a struct with the following "
3896 #. si_trapno seems to be only used on SPARC and Alpha;
3897 #. this page could use a little more detail on its purpose there.
3898 #. In the kernel: si_tid
3900 #: build/C/man2/sigaction.2:289
3904 " int si_signo; /* Signal number */\n"
3905 " int si_errno; /* An errno value */\n"
3906 " int si_code; /* Signal code */\n"
3907 " int si_trapno; /* Trap number that caused\n"
3908 " hardware-generated signal\n"
3909 " (unused on most architectures) */\n"
3910 " pid_t si_pid; /* Sending process ID */\n"
3911 " uid_t si_uid; /* Real user ID of sending process */\n"
3912 " int si_status; /* Exit value or signal */\n"
3913 " clock_t si_utime; /* User time consumed */\n"
3914 " clock_t si_stime; /* System time consumed */\n"
3915 " sigval_t si_value; /* Signal value */\n"
3916 " int si_int; /* POSIX.1b signal */\n"
3917 " void *si_ptr; /* POSIX.1b signal */\n"
3918 " int si_overrun; /* Timer overrun count; POSIX.1b timers */\n"
3919 " int si_timerid; /* Timer ID; POSIX.1b timers */\n"
3920 " void *si_addr; /* Memory location which caused fault */\n"
3921 " long si_band; /* Band event (was I<int> in\n"
3922 " glibc 2.3.2 and earlier) */\n"
3923 " int si_fd; /* File descriptor */\n"
3924 " short si_addr_lsb; /* Least significant bit of address\n"
3925 " (since Linux 2.6.32) */\n"
3930 #: build/C/man2/sigaction.2:298
3932 "I<si_signo>, I<si_errno> and I<si_code> are defined for all signals. "
3933 "(I<si_errno> is generally unused on Linux.) The rest of the struct may be a "
3934 "union, so that one should read only the fields that are meaningful for the "
3939 #: build/C/man2/sigaction.2:313
3941 "Signals sent with B<kill>(2) and B<sigqueue>(3) fill in I<si_pid> and "
3942 "I<si_uid>. In addition, signals sent with B<sigqueue>(3) fill in I<si_int> "
3943 "and I<si_ptr> with the values specified by the sender of the signal; see "
3944 "B<sigqueue>(3) for more details."
3948 #: build/C/man2/sigaction.2:329
3950 "Signals sent by POSIX.1b timers (since Linux 2.6) fill in I<si_overrun> and "
3951 "I<si_timerid>. The I<si_timerid> field is an internal ID used by the kernel "
3952 "to identify the timer; it is not the same as the timer ID returned by "
3953 "B<timer_create>(2). The I<si_overrun> field is the timer overrun count; "
3954 "this is the same information as is obtained by a call to "
3955 "B<timer_getoverrun>(2). These fields are nonstandard Linux extensions."
3959 #: build/C/man2/sigaction.2:344
3961 "Signals sent for message queue notification (see the description of "
3962 "B<SIGEV_SIGNAL> in B<mq_notify>(3)) fill in I<si_int>/I<si_ptr>, with the "
3963 "I<sigev_value> supplied to B<mq_notify>(3); I<si_pid>, with the process ID "
3964 "of the message sender; and I<si_uid>, with the real user ID of the message "
3969 #. When si_utime and si_stime where originally implemented, the
3970 #. measurement unit was HZ, which was the same as clock ticks
3971 #. (sysconf(_SC_CLK_TCK)). In 2.6, HZ became configurable, and
3972 #. was *still* used as the unit to return the info these fields,
3973 #. with the result that the field values depended on the the
3974 #. configured HZ. Of course, the should have been measured in
3975 #. USER_HZ instead, so that sysconf(_SC_CLK_TCK) could be used to
3976 #. convert to seconds. I have a queued patch to fix this:
3977 #. http://thread.gmane.org/gmane.linux.kernel/698061/ .
3978 #. This patch made it into 2.6.27.
3979 #. But note that these fields still don't return the times of
3980 #. waited-for children (as is done by getrusage() and times()
3981 #. and wait4()). Solaris 8 does include child times.
3983 #: build/C/man2/sigaction.2:391
3985 "B<SIGCHLD> fills in I<si_pid>, I<si_uid>, I<si_status>, I<si_utime>, and "
3986 "I<si_stime>, providing information about the child. The I<si_pid> field is "
3987 "the process ID of the child; I<si_uid> is the child's real user ID. The "
3988 "I<si_status> field contains the exit status of the child (if I<si_code> is "
3989 "B<CLD_EXITED>), or the signal number that caused the process to change "
3990 "state. The I<si_utime> and I<si_stime> contain the user and system CPU time "
3991 "used by the child process; these fields do not include the times used by "
3992 "waited-for children (unlike B<getrusage>(2) and B<times>(2)). In kernels "
3993 "up to 2.6, and since 2.6.27, these fields report CPU time in units of "
3994 "I<sysconf(_SC_CLK_TCK)>. In 2.6 kernels before 2.6.27, a bug meant that "
3995 "these fields reported time in units of the (configurable) system jiffy (see "
3999 #. FIXME SIGTRAP also sets the following for ptrace_notify() ?
4000 #. info.si_code = exit_code;
4001 #. info.si_pid = task_pid_vnr(current);
4002 #. info.si_uid = current_uid(); /* Real UID */
4004 #: build/C/man2/sigaction.2:427
4006 "B<SIGILL>, B<SIGFPE>, B<SIGSEGV>, B<SIGBUS>, and B<SIGTRAP> fill in "
4007 "I<si_addr> with the address of the fault. On some architectures, these "
4008 "signals also fill in the I<si_trapno> field. Some suberrors of B<SIGBUS>, "
4009 "in particular B<BUS_MCEERR_AO> and B<BUS_MCEERR_AR>, also fill in "
4010 "I<si_addr_lsb>. This field indicates the least significant bit of the "
4011 "reported address and therefore the extent of the corruption. For example, "
4012 "if a full page was corrupted, I<si_addr_lsb> contains "
4013 "I<log2(sysconf(_SC_PAGESIZE))>. B<BUS_MCERR_*> and I<si_addr_lsb> are "
4014 "Linux-specific extensions."
4018 #: build/C/man2/sigaction.2:441
4020 "B<SIGIO>/B<SIGPOLL> (the two names are synonyms on Linux) fills in "
4021 "I<si_band> and I<si_fd>. The I<si_band> event is a bit mask containing the "
4022 "same values as are filled in the I<revents> field by B<poll>(2). The "
4023 "I<si_fd> field indicates the file descriptor for which the I/O event "
4028 #: build/C/man2/sigaction.2:448
4030 "I<si_code> is a value (not a bit mask) indicating why this signal was "
4031 "sent. The following list shows the values which can be placed in I<si_code> "
4032 "for any signal, along with reason that the signal was generated."
4036 #: build/C/man2/sigaction.2:449
4042 #: build/C/man2/sigaction.2:452 build/C/man7/signal.7:111
4048 #: build/C/man2/sigaction.2:452
4050 msgid "B<SI_KERNEL>"
4054 #: build/C/man2/sigaction.2:455
4055 msgid "Sent by the kernel."
4059 #: build/C/man2/sigaction.2:455
4065 #: build/C/man2/sigaction.2:458 build/C/man7/signal.7:128
4067 msgid "B<sigqueue>(3)"
4071 #: build/C/man2/sigaction.2:458
4077 #: build/C/man2/sigaction.2:461
4078 msgid "POSIX timer expired"
4082 #: build/C/man2/sigaction.2:461
4088 #: build/C/man2/sigaction.2:465
4089 msgid "POSIX message queue state changed (since Linux 2.6.6); see B<mq_notify>(3)"
4093 #: build/C/man2/sigaction.2:465
4095 msgid "B<SI_ASYNCIO>"
4099 #: build/C/man2/sigaction.2:468
4100 msgid "AIO completed"
4104 #: build/C/man2/sigaction.2:468
4110 #: build/C/man2/sigaction.2:477
4112 "Queued B<SIGIO> (only in kernels up to Linux 2.2; from Linux 2.4 onward "
4113 "B<SIGIO>/B<SIGPOLL> fills in I<si_code> as described below)."
4117 #: build/C/man2/sigaction.2:477
4122 #. SI_DETHREAD is defined in 2.6.9 sources, but isn't implemented
4123 #. It appears to have been an idea that was tried during 2.5.6
4124 #. through to 2.5.24 and then was backed out.
4126 #: build/C/man2/sigaction.2:486
4127 msgid "B<tkill>(2) or B<tgkill>(2) (since Linux 2.4.19)"
4131 #: build/C/man2/sigaction.2:493
4132 msgid "The following values can be placed in I<si_code> for a B<SIGILL> signal:"
4136 #: build/C/man2/sigaction.2:494
4138 msgid "B<ILL_ILLOPC>"
4142 #: build/C/man2/sigaction.2:497
4143 msgid "illegal opcode"
4147 #: build/C/man2/sigaction.2:497
4149 msgid "B<ILL_ILLOPN>"
4153 #: build/C/man2/sigaction.2:500
4154 msgid "illegal operand"
4158 #: build/C/man2/sigaction.2:500
4160 msgid "B<ILL_ILLADR>"
4164 #: build/C/man2/sigaction.2:503
4165 msgid "illegal addressing mode"
4169 #: build/C/man2/sigaction.2:503
4171 msgid "B<ILL_ILLTRP>"
4175 #: build/C/man2/sigaction.2:506
4176 msgid "illegal trap"
4180 #: build/C/man2/sigaction.2:506
4182 msgid "B<ILL_PRVOPC>"
4186 #: build/C/man2/sigaction.2:509
4187 msgid "privileged opcode"
4191 #: build/C/man2/sigaction.2:509
4193 msgid "B<ILL_PRVREG>"
4197 #: build/C/man2/sigaction.2:512
4198 msgid "privileged register"
4202 #: build/C/man2/sigaction.2:512
4204 msgid "B<ILL_COPROC>"
4208 #: build/C/man2/sigaction.2:515
4209 msgid "coprocessor error"
4213 #: build/C/man2/sigaction.2:515
4215 msgid "B<ILL_BADSTK>"
4219 #: build/C/man2/sigaction.2:518
4220 msgid "internal stack error"
4224 #: build/C/man2/sigaction.2:525
4225 msgid "The following values can be placed in I<si_code> for a B<SIGFPE> signal:"
4229 #: build/C/man2/sigaction.2:526
4231 msgid "B<FPE_INTDIV>"
4235 #: build/C/man2/sigaction.2:529
4236 msgid "integer divide by zero"
4240 #: build/C/man2/sigaction.2:529
4242 msgid "B<FPE_INTOVF>"
4246 #: build/C/man2/sigaction.2:532
4247 msgid "integer overflow"
4251 #: build/C/man2/sigaction.2:532
4253 msgid "B<FPE_FLTDIV>"
4257 #: build/C/man2/sigaction.2:535
4258 msgid "floating-point divide by zero"
4262 #: build/C/man2/sigaction.2:535
4264 msgid "B<FPE_FLTOVF>"
4268 #: build/C/man2/sigaction.2:538
4269 msgid "floating-point overflow"
4273 #: build/C/man2/sigaction.2:538
4275 msgid "B<FPE_FLTUND>"
4279 #: build/C/man2/sigaction.2:541
4280 msgid "floating-point underflow"
4284 #: build/C/man2/sigaction.2:541
4286 msgid "B<FPE_FLTRES>"
4290 #: build/C/man2/sigaction.2:544
4291 msgid "floating-point inexact result"
4295 #: build/C/man2/sigaction.2:544
4297 msgid "B<FPE_FLTINV>"
4301 #: build/C/man2/sigaction.2:547
4302 msgid "floating-point invalid operation"
4306 #: build/C/man2/sigaction.2:547
4308 msgid "B<FPE_FLTSUB>"
4312 #: build/C/man2/sigaction.2:550
4313 msgid "subscript out of range"
4317 #: build/C/man2/sigaction.2:557
4318 msgid "The following values can be placed in I<si_code> for a B<SIGSEGV> signal:"
4322 #: build/C/man2/sigaction.2:558
4324 msgid "B<SEGV_MAPERR>"
4328 #: build/C/man2/sigaction.2:561
4329 msgid "address not mapped to object"
4333 #: build/C/man2/sigaction.2:561
4335 msgid "B<SEGV_ACCERR>"
4339 #: build/C/man2/sigaction.2:564
4340 msgid "invalid permissions for mapped object"
4344 #: build/C/man2/sigaction.2:571
4345 msgid "The following values can be placed in I<si_code> for a B<SIGBUS> signal:"
4349 #: build/C/man2/sigaction.2:572
4351 msgid "B<BUS_ADRALN>"
4355 #: build/C/man2/sigaction.2:575
4356 msgid "invalid address alignment"
4360 #: build/C/man2/sigaction.2:575
4362 msgid "B<BUS_ADRERR>"
4366 #: build/C/man2/sigaction.2:578
4367 msgid "nonexistent physical address"
4371 #: build/C/man2/sigaction.2:578
4373 msgid "B<BUS_OBJERR>"
4377 #: build/C/man2/sigaction.2:581
4378 msgid "object-specific hardware error"
4382 #: build/C/man2/sigaction.2:581
4384 msgid "B<BUS_MCEERR_AR> (since Linux 2.6.32)"
4388 #: build/C/man2/sigaction.2:584
4389 msgid "Hardware memory error consumed on a machine check; action required."
4393 #: build/C/man2/sigaction.2:584
4395 msgid "B<BUS_MCEERR_AO> (since Linux 2.6.32)"
4399 #: build/C/man2/sigaction.2:587
4400 msgid "Hardware memory error detected in process but not consumed; action optional."
4404 #: build/C/man2/sigaction.2:594
4405 msgid "The following values can be placed in I<si_code> for a B<SIGTRAP> signal:"
4409 #: build/C/man2/sigaction.2:595
4411 msgid "B<TRAP_BRKPT>"
4415 #: build/C/man2/sigaction.2:598
4416 msgid "process breakpoint"
4420 #: build/C/man2/sigaction.2:598
4422 msgid "B<TRAP_TRACE>"
4426 #: build/C/man2/sigaction.2:601
4427 msgid "process trace trap"
4431 #: build/C/man2/sigaction.2:601
4433 msgid "B<TRAP_BRANCH> (since Linux 2.4)"
4437 #: build/C/man2/sigaction.2:604
4438 msgid "process taken branch trap"
4442 #: build/C/man2/sigaction.2:604
4444 msgid "B<TRAP_HWBKPT> (since Linux 2.4)"
4448 #: build/C/man2/sigaction.2:607
4449 msgid "hardware breakpoint/watchpoint"
4453 #: build/C/man2/sigaction.2:614
4454 msgid "The following values can be placed in I<si_code> for a B<SIGCHLD> signal:"
4458 #: build/C/man2/sigaction.2:615
4460 msgid "B<CLD_EXITED>"
4464 #: build/C/man2/sigaction.2:618
4465 msgid "child has exited"
4469 #: build/C/man2/sigaction.2:618
4471 msgid "B<CLD_KILLED>"
4475 #: build/C/man2/sigaction.2:621
4476 msgid "child was killed"
4480 #: build/C/man2/sigaction.2:621
4482 msgid "B<CLD_DUMPED>"
4486 #: build/C/man2/sigaction.2:624
4487 msgid "child terminated abnormally"
4491 #: build/C/man2/sigaction.2:624
4493 msgid "B<CLD_TRAPPED>"
4497 #: build/C/man2/sigaction.2:627
4498 msgid "traced child has trapped"
4502 #: build/C/man2/sigaction.2:627
4504 msgid "B<CLD_STOPPED>"
4508 #: build/C/man2/sigaction.2:630
4509 msgid "child has stopped"
4513 #: build/C/man2/sigaction.2:630
4515 msgid "B<CLD_CONTINUED>"
4519 #: build/C/man2/sigaction.2:633
4520 msgid "stopped child has continued (since Linux 2.6.9)"
4524 #: build/C/man2/sigaction.2:640
4526 "The following values can be placed in I<si_code> for a B<SIGIO>/B<SIGPOLL> "
4531 #: build/C/man2/sigaction.2:641
4537 #: build/C/man2/sigaction.2:644
4538 msgid "data input available"
4542 #: build/C/man2/sigaction.2:644
4548 #: build/C/man2/sigaction.2:647
4549 msgid "output buffers available"
4553 #: build/C/man2/sigaction.2:647
4559 #: build/C/man2/sigaction.2:650
4560 msgid "input message available"
4564 #: build/C/man2/sigaction.2:650
4570 #: build/C/man2/sigaction.2:653
4575 #: build/C/man2/sigaction.2:653
4581 #: build/C/man2/sigaction.2:656
4582 msgid "high priority input available"
4586 #: build/C/man2/sigaction.2:656
4592 #: build/C/man2/sigaction.2:659
4593 msgid "device disconnected"
4597 #: build/C/man2/sigaction.2:665
4599 "B<sigaction>() returns 0 on success; on error, -1 is returned, and I<errno> "
4600 "is set to indicate the error."
4604 #: build/C/man2/sigaction.2:670
4606 "I<act> or I<oldact> points to memory which is not a valid part of the "
4607 "process address space."
4611 #: build/C/man2/sigaction.2:677
4613 "An invalid signal was specified. This will also be generated if an attempt "
4614 "is made to change the action for B<SIGKILL> or B<SIGSTOP>, which cannot be "
4615 "caught or ignored."
4618 #. SVr4 does not document the EINTR condition.
4620 #: build/C/man2/sigaction.2:680
4621 msgid "POSIX.1-2001, SVr4."
4625 #: build/C/man2/sigaction.2:688 build/C/man7/signal.7:105
4627 "A child created via B<fork>(2) inherits a copy of its parent's signal "
4628 "dispositions. During an B<execve>(2), the dispositions of handled signals "
4629 "are reset to the default; the dispositions of ignored signals are left "
4634 #: build/C/man2/sigaction.2:706 build/C/man2/signal.2:134
4636 "According to POSIX, the behavior of a process is undefined after it ignores "
4637 "a B<SIGFPE>, B<SIGILL>, or B<SIGSEGV> signal that was not generated by "
4638 "B<kill>(2) or B<raise>(3). Integer division by zero has undefined result. "
4639 "On some architectures it will generate a B<SIGFPE> signal. (Also dividing "
4640 "the most negative integer by -1 may generate B<SIGFPE>.) Ignoring this "
4641 "signal might lead to an endless loop."
4645 #: build/C/man2/sigaction.2:723
4647 "POSIX.1-1990 disallowed setting the action for B<SIGCHLD> to B<SIG_IGN>. "
4648 "POSIX.1-2001 allows this possibility, so that ignoring B<SIGCHLD> can be "
4649 "used to prevent the creation of zombies (see B<wait>(2)). Nevertheless, the "
4650 "historical BSD and System\\ V behaviors for ignoring B<SIGCHLD> differ, so "
4651 "that the only completely portable method of ensuring that terminated "
4652 "children do not become zombies is to catch the B<SIGCHLD> signal and perform "
4653 "a B<wait>(2) or similar."
4657 #: build/C/man2/sigaction.2:736
4659 "POSIX.1-1990 specified only B<SA_NOCLDSTOP>. POSIX.1-2001 added "
4660 "B<SA_NOCLDWAIT>, B<SA_RESETHAND>, B<SA_NODEFER>, and B<SA_SIGINFO>. Use of "
4661 "these latter values in I<sa_flags> may be less portable in applications "
4662 "intended for older UNIX implementations."
4666 #: build/C/man2/sigaction.2:740
4667 msgid "The B<SA_RESETHAND> flag is compatible with the SVr4 flag of the same name."
4671 #: build/C/man2/sigaction.2:750
4673 "The B<SA_NODEFER> flag is compatible with the SVr4 flag of the same name "
4674 "under kernels 1.3.9 and newer. On older kernels the Linux implementation "
4675 "allowed the receipt of any signal, not just the one we are installing "
4676 "(effectively overriding any I<sa_mask> settings)."
4680 #: build/C/man2/sigaction.2:756
4682 "B<sigaction>() can be called with a NULL second argument to query the "
4683 "current signal handler. It can also be used to check whether a given signal "
4684 "is valid for the current machine by calling it with NULL second and third "
4689 #: build/C/man2/sigaction.2:762
4691 "It is not possible to block B<SIGKILL> or B<SIGSTOP> (by specifying them in "
4692 "I<sa_mask>). Attempts to do so are silently ignored."
4696 #: build/C/man2/sigaction.2:766 build/C/man2/sigpending.2:70 build/C/man2/sigprocmask.2:144 build/C/man2/sigsuspend.2:108
4697 msgid "See B<sigsetops>(3) for details on manipulating signal sets."
4701 #: build/C/man2/sigaction.2:771
4703 "See B<signal>(7) for a list of the async-signal-safe functions that can be "
4704 "safely called inside from inside a signal handler."
4708 #: build/C/man2/sigaction.2:771
4710 msgid "Undocumented"
4714 #: build/C/man2/sigaction.2:781
4716 "Before the introduction of B<SA_SIGINFO> it was also possible to get some "
4717 "additional information, namely by using a I<sa_handler> with second argument "
4718 "of type I<struct sigcontext>. See the relevant Linux kernel sources for "
4719 "details. This use is obsolete now."
4723 #: build/C/man2/sigaction.2:790
4725 "In kernels up to and including 2.6.13, specifying B<SA_NODEFER> in "
4726 "I<sa_flags> prevents not only the delivered signal from being masked during "
4727 "execution of the handler, but also the signals specified in I<sa_mask>. "
4728 "This bug was fixed in kernel 2.6.14."
4732 #: build/C/man2/sigaction.2:793
4733 msgid "See B<mprotect>(2)."
4737 #: build/C/man2/sigaction.2:813
4739 "B<kill>(1), B<kill>(2), B<killpg>(2), B<pause>(2), B<restart_syscall>(2), "
4740 "B<sigaltstack>(2), B<signal>(2), B<signalfd>(2), B<sigpending>(2), "
4741 "B<sigprocmask>(2), B<sigsuspend>(2), B<wait>(2), B<raise>(3), "
4742 "B<siginterrupt>(3), B<sigqueue>(3), B<sigsetops>(3), B<sigvec>(3), "
4743 "B<core>(5), B<signal>(7)"
4747 #: build/C/man2/sigaltstack.2:27
4753 #: build/C/man2/sigaltstack.2:27
4759 #: build/C/man2/sigaltstack.2:30
4760 msgid "sigaltstack - set and/or get signal stack context"
4764 #: build/C/man2/sigaltstack.2:34
4765 msgid "B<int sigaltstack(const stack_t *>I<ss>B<, stack_t *>I<oss>B<);>"
4769 #: build/C/man2/sigaltstack.2:41
4770 msgid "B<sigaltstack>():"
4774 #: build/C/man2/sigaltstack.2:48 build/C/man3/siginterrupt.3:53 build/C/man2/wait.2:80
4775 msgid "|| /* Since glibc 2.12: */ _POSIX_C_SOURCE\\ E<gt>=\\ 200809L"
4779 #: build/C/man2/sigaltstack.2:60
4781 "B<sigaltstack>() allows a process to define a new alternate signal stack "
4782 "and/or retrieve the state of an existing alternate signal stack. An "
4783 "alternate signal stack is used during the execution of a signal handler if "
4784 "the establishment of that handler (see B<sigaction>(2)) requested it."
4788 #: build/C/man2/sigaltstack.2:63
4790 "The normal sequence of events for using an alternate signal stack is the "
4795 #: build/C/man2/sigaltstack.2:63 build/C/man7/signal.7:387
4801 #: build/C/man2/sigaltstack.2:67
4802 msgid "Allocate an area of memory to be used for the alternate signal stack."
4806 #: build/C/man2/sigaltstack.2:67 build/C/man7/signal.7:391
4812 #: build/C/man2/sigaltstack.2:73
4814 "Use B<sigaltstack>() to inform the system of the existence and location of "
4815 "the alternate signal stack."
4819 #: build/C/man2/sigaltstack.2:73 build/C/man7/signal.7:411
4825 #: build/C/man2/sigaltstack.2:80
4827 "When establishing a signal handler using B<sigaction>(2), inform the system "
4828 "that the signal handler should be executed on the alternate signal stack by "
4829 "specifying the B<SA_ONSTACK> flag."
4833 #: build/C/man2/sigaltstack.2:88
4835 "The I<ss> argument is used to specify a new alternate signal stack, while "
4836 "the I<oss> argument is used to retrieve information about the currently "
4837 "established signal stack. If we are interested in performing just one of "
4838 "these tasks, then the other argument can be specified as NULL. Each of "
4839 "these arguments is a structure of the following type:"
4843 #: build/C/man2/sigaltstack.2:96
4846 "typedef struct {\n"
4847 " void *ss_sp; /* Base address of stack */\n"
4848 " int ss_flags; /* Flags */\n"
4849 " size_t ss_size; /* Number of bytes in stack */\n"
4854 #: build/C/man2/sigaltstack.2:107
4856 "To establish a new alternate signal stack, I<ss.ss_flags> is set to zero, "
4857 "and I<ss.ss_sp> and I<ss.ss_size> specify the starting address and size of "
4858 "the stack. The constant B<SIGSTKSZ> is defined to be large enough to cover "
4859 "the usual size requirements for an alternate signal stack, and the constant "
4860 "B<MINSIGSTKSZ> defines the minimum size required to execute a signal "
4865 #: build/C/man2/sigaltstack.2:111
4867 "When a signal handler is invoked on the alternate stack, the kernel "
4868 "automatically aligns the address given in I<ss.ss_sp> to a suitable address "
4869 "boundary for the underlying hardware architecture."
4873 #: build/C/man2/sigaltstack.2:116
4875 "To disable an existing stack, specify I<ss.ss_flags> as B<SS_DISABLE>. In "
4876 "this case, the remaining fields in I<ss> are ignored."
4880 #: build/C/man2/sigaltstack.2:124
4882 "If I<oss> is not NULL, then it is used to return information about the "
4883 "alternate signal stack which was in effect prior to the call to "
4884 "B<sigaltstack>(). The I<oss.ss_sp> and I<oss.ss_size> fields return the "
4885 "starting address and size of that stack. The I<oss.ss_flags> may return "
4886 "either of the following values:"
4890 #: build/C/man2/sigaltstack.2:124
4892 msgid "B<SS_ONSTACK>"
4896 #: build/C/man2/sigaltstack.2:130
4898 "The process is currently executing on the alternate signal stack. (Note "
4899 "that it is not possible to change the alternate signal stack if the process "
4900 "is currently executing on it.)"
4904 #: build/C/man2/sigaltstack.2:130
4906 msgid "B<SS_DISABLE>"
4910 #: build/C/man2/sigaltstack.2:133
4911 msgid "The alternate signal stack is currently disabled."
4915 #: build/C/man2/sigaltstack.2:137
4917 "B<sigaltstack>() returns 0 on success, or -1 on failure with I<errno> set "
4918 "to indicate the error."
4922 #: build/C/man2/sigaltstack.2:142
4924 "Either I<ss> or I<oss> is not NULL and points to an area outside of the "
4925 "process's address space."
4929 #: build/C/man2/sigaltstack.2:147
4931 "I<ss> is not NULL and the I<ss_flags> field contains a nonzero value other "
4932 "than B<SS_DISABLE>."
4936 #: build/C/man2/sigaltstack.2:153
4938 "The specified size of the new alternate signal stack I<ss.ss_size> as less "
4943 #: build/C/man2/sigaltstack.2:158
4945 "An attempt was made to change the alternate signal stack while it was active "
4946 "(i.e., the process was already executing on the current alternate signal "
4951 #: build/C/man2/sigaltstack.2:160
4952 msgid "SUSv2, SVr4, POSIX.1-2001."
4956 #: build/C/man2/sigaltstack.2:168
4958 "The most common usage of an alternate signal stack is to handle the "
4959 "B<SIGSEGV> signal that is generated if the space available for the normal "
4960 "process stack is exhausted: in this case, a signal handler for B<SIGSEGV> "
4961 "cannot be invoked on the process stack; if we wish to handle it, we must use "
4962 "an alternate signal stack."
4966 #: build/C/man2/sigaltstack.2:178
4968 "Establishing an alternate signal stack is useful if a process expects that "
4969 "it may exhaust its standard stack. This may occur, for example, because the "
4970 "stack grows so large that it encounters the upwardly growing heap, or it "
4971 "reaches a limit established by a call to B<setrlimit(RLIMIT_STACK, &rlim)>. "
4972 "If the standard stack is exhausted, the kernel sends the process a "
4973 "B<SIGSEGV> signal. In these circumstances the only way to catch this signal "
4974 "is on an alternate signal stack."
4978 #: build/C/man2/sigaltstack.2:184
4980 "On most hardware architectures supported by Linux, stacks grow downward. "
4981 "B<sigaltstack>() automatically takes account of the direction of stack "
4986 #: build/C/man2/sigaltstack.2:193
4988 "Functions called from a signal handler executing on an alternate signal "
4989 "stack will also use the alternate signal stack. (This also applies to any "
4990 "handlers invoked for other signals while the process is executing on the "
4991 "alternate signal stack.) Unlike the standard stack, the system does not "
4992 "automatically extend the alternate signal stack. Exceeding the allocated "
4993 "size of the alternate signal stack will lead to unpredictable results."
4997 #: build/C/man2/sigaltstack.2:201
4999 "A successful call to B<execve>(2) removes any existing alternate signal "
5000 "stack. A child process created via B<fork>(2) inherits a copy of its "
5001 "parent's alternate signal stack settings."
5005 #: build/C/man2/sigaltstack.2:210
5007 "B<sigaltstack>() supersedes the older B<sigstack>() call. For backward "
5008 "compatibility, glibc also provides B<sigstack>(). All new applications "
5009 "should be written using B<sigaltstack>()."
5013 #: build/C/man2/sigaltstack.2:210 build/C/man3/sigpause.3:66
5019 #: build/C/man2/sigaltstack.2:217
5021 "4.2BSD had a B<sigstack>() system call. It used a slightly different "
5022 "struct, and had the major disadvantage that the caller had to know the "
5023 "direction of stack growth."
5027 #: build/C/man2/sigaltstack.2:220
5028 msgid "The following code segment demonstrates the use of B<sigaltstack>():"
5032 #: build/C/man2/sigaltstack.2:224
5034 msgid "stack_t ss;\n"
5038 #: build/C/man2/sigaltstack.2:232
5041 "ss.ss_sp = malloc(SIGSTKSZ);\n"
5042 "if (ss.ss_sp == NULL)\n"
5043 " /* Handle error */;\n"
5044 "ss.ss_size = SIGSTKSZ;\n"
5045 "ss.ss_flags = 0;\n"
5046 "if (sigaltstack(&ss, NULL) == -1)\n"
5047 " /* Handle error */;\n"
5051 #: build/C/man2/sigaltstack.2:241
5053 "B<execve>(2), B<setrlimit>(2), B<sigaction>(2), B<siglongjmp>(3), "
5054 "B<sigsetjmp>(3), B<signal>(7)"
5058 #: build/C/man7/sigevent.7:26
5064 #: build/C/man7/sigevent.7:26
5070 #: build/C/man7/sigevent.7:29
5071 msgid "sigevent - structure for notification from asynchronous routines"
5075 #: build/C/man7/sigevent.7:36
5078 "union sigval { /* Data passed with notification */\n"
5079 " int sival_int; /* Integer value */\n"
5080 " void *sival_ptr; /* Pointer value */\n"
5085 #: build/C/man7/sigevent.7:51
5088 "struct sigevent {\n"
5089 " int sigev_notify; /* Notification method */\n"
5090 " int sigev_signo; /* Notification signal */\n"
5091 " union sigval sigev_value; /* Data passed with\n"
5092 " notification */\n"
5093 " void (*sigev_notify_function) (union sigval);\n"
5094 " /* Function used for thread\n"
5095 " notification (SIGEV_THREAD) */\n"
5096 " void *sigev_notify_attributes;\n"
5097 " /* Attributes for notification thread\n"
5098 " (SIGEV_THREAD) */\n"
5099 " pid_t sigev_notify_thread_id;\n"
5100 " /* ID of thread to signal (SIGEV_THREAD_ID) */\n"
5105 #: build/C/man7/sigevent.7:60
5107 "The I<sigevent> structure is used by various APIs to describe the way a "
5108 "process is to be notified about an event (e.g., completion of an "
5109 "asynchronous request, expiration of a timer, or the arrival of a message)."
5113 #: build/C/man7/sigevent.7:68
5115 "The definition shown in the SYNOPSIS is approximate: some of the fields in "
5116 "the I<sigevent> structure may be defined as part of a union. Programs "
5117 "should employ only those fields relevant to the value specified in "
5122 #: build/C/man7/sigevent.7:73
5124 "The I<sigev_notify> field specifies how notification is to be performed. "
5125 "This field can have one of the following values:"
5129 #: build/C/man7/sigevent.7:73 build/C/man2/timer_create.2:107
5131 msgid "B<SIGEV_NONE>"
5135 #: build/C/man7/sigevent.7:76
5136 msgid "A \"null\" notification: don't do anything when the event occurs."
5140 #: build/C/man7/sigevent.7:76 build/C/man2/timer_create.2:112
5142 msgid "B<SIGEV_SIGNAL>"
5146 #: build/C/man7/sigevent.7:80
5147 msgid "Notify the process by sending the signal specified in I<sigev_signo>."
5151 #: build/C/man7/sigevent.7:87
5153 "If the signal is caught with a signal handler that was registered using the "
5154 "B<sigaction>(2) B<SA_SIGINFO> flag, then the following fields are set in "
5155 "the I<siginfo_t> structure that is passed as the second argument of the "
5160 #: build/C/man7/sigevent.7:92
5162 "This field is set to a value that depends on the API delivering the "
5167 #: build/C/man7/sigevent.7:92 build/C/man2/wait.2:302
5173 #: build/C/man7/sigevent.7:96
5175 "This field is set to the signal number (i.e., the same value as in "
5180 #: build/C/man7/sigevent.7:100
5181 msgid "This field is set to the value specified in I<sigev_value>."
5185 #: build/C/man7/sigevent.7:105
5187 "Depending on the API, other fields may also be set in the I<siginfo_t> "
5192 #: build/C/man7/sigevent.7:108
5194 "The same information is also available if the signal is accepted using "
5195 "B<sigwaitinfo>(2)."
5199 #: build/C/man7/sigevent.7:108 build/C/man2/timer_create.2:130
5201 msgid "B<SIGEV_THREAD>"
5205 #: build/C/man7/sigevent.7:125
5207 "Notify the process by invoking I<sigev_notify_function> \"as if\" it were "
5208 "the start function of a new thread. (Among the implementation possibilities "
5209 "here are that each timer notification could result in the creation of a new "
5210 "thread, or that a single thread is created to receive all notifications.) "
5211 "The function is invoked with I<sigev_value> as its sole argument. If "
5212 "I<sigev_notify_attributes> is not NULL, it should point to a "
5213 "I<pthread_attr_t> structure that defines attributes for the new thread (see "
5214 "B<pthread_attr_init>(3))."
5218 #: build/C/man7/sigevent.7:125 build/C/man2/timer_create.2:138
5220 msgid "B<SIGEV_THREAD_ID> (Linux-specific)"
5223 #. | SIGEV_SIGNAL vs not?
5225 #: build/C/man7/sigevent.7:130
5226 msgid "Currently used only by POSIX timers; see B<timer_create>(2)."
5230 #: build/C/man7/sigevent.7:132 build/C/man2/sigpending.2:66 build/C/man2/sigprocmask.2:114 build/C/man3/sigqueue.3:121 build/C/man3/sigsetops.3:146 build/C/man2/sigsuspend.2:86 build/C/man3/sigwait.3:87 build/C/man2/sigwaitinfo.2:135 build/C/man2/timer_create.2:195 build/C/man2/timer_delete.2:69 build/C/man2/timer_getoverrun.2:99 build/C/man2/timer_settime.2:209
5231 msgid "POSIX.1-2001."
5235 #: build/C/man7/sigevent.7:142
5237 "B<timer_create>(2), B<aio_fsync>(3), B<aio_read>(3), B<aio_write>(3), "
5238 "B<getaddrinfo_a>(3), B<lio_listio>(3), B<mq_notify>(3), B<aio>(7), "
5243 #: build/C/man3/siginterrupt.3:31
5245 msgid "SIGINTERRUPT"
5249 #: build/C/man3/siginterrupt.3:31 build/C/man2/signal.2:36 build/C/man2/sigprocmask.2:29 build/C/man2/sigsuspend.2:29
5255 #: build/C/man3/siginterrupt.3:34
5256 msgid "siginterrupt - allow signals to interrupt system calls"
5260 #: build/C/man3/siginterrupt.3:39
5262 msgid "B<int siginterrupt(int >I<sig>B<, int >I<flag>B<);>\n"
5266 #: build/C/man3/siginterrupt.3:47
5267 msgid "B<siginterrupt>():"
5271 #: build/C/man3/siginterrupt.3:64
5273 "The B<siginterrupt>() function changes the restart behavior when a system "
5274 "call is interrupted by the signal I<sig>. If the I<flag> argument is false "
5275 "(0), then system calls will be restarted if interrupted by the specified "
5276 "signal I<sig>. This is the default behavior in Linux."
5280 #: build/C/man3/siginterrupt.3:69
5282 "If the I<flag> argument is true (1) and no data has been transferred, then a "
5283 "system call interrupted by the signal I<sig> will return -1 and I<errno> "
5284 "will be set to B<EINTR>."
5288 #: build/C/man3/siginterrupt.3:73
5290 "If the I<flag> argument is true (1) and data transfer has started, then the "
5291 "system call will be interrupted and will return the actual amount of data "
5296 #: build/C/man3/siginterrupt.3:83
5298 "The B<siginterrupt>() function returns 0 on success. It returns -1 if the "
5299 "signal number I<sig> is invalid, with I<errno> set to indicate the cause of "
5304 #: build/C/man3/siginterrupt.3:87
5305 msgid "The specified signal number is invalid."
5309 #: build/C/man3/siginterrupt.3:96
5311 "4.3BSD, POSIX.1-2001. POSIX.1-2008 marks B<siginterrupt>() as obsolete, "
5312 "recommending the use of B<sigaction>(2) with the B<SA_RESTART> flag "
5317 #: build/C/man3/siginterrupt.3:98
5318 msgid "B<signal>(2)"
5322 #: build/C/man2/signal.2:36 build/C/man7/signal.7:46
5328 #: build/C/man2/signal.2:39
5329 msgid "signal - ANSI C signal handling"
5333 #: build/C/man2/signal.2:45
5334 msgid "B<sighandler_t signal(int >I<signum>B<, sighandler_t >I<handler>B<);>"
5338 #: build/C/man2/signal.2:54
5340 "The behavior of B<signal>() varies across UNIX versions, and has also "
5341 "varied historically across different versions of Linux. B<Avoid its use>: "
5342 "use B<sigaction>(2) instead. See I<Portability> below."
5346 #: build/C/man2/signal.2:64
5348 "B<signal>() sets the disposition of the signal I<signum> to I<handler>, "
5349 "which is either B<SIG_IGN>, B<SIG_DFL>, or the address of a "
5350 "programmer-defined function (a \"signal handler\")."
5354 #: build/C/man2/signal.2:68
5356 "If the signal I<signum> is delivered to the process, then one of the "
5357 "following happens:"
5361 #: build/C/man2/signal.2:73
5362 msgid "If the disposition is set to B<SIG_IGN>, then the signal is ignored."
5366 #: build/C/man2/signal.2:80
5368 "If the disposition is set to B<SIG_DFL>, then the default action associated "
5369 "with the signal (see B<signal>(7)) occurs."
5373 #: build/C/man2/signal.2:91
5375 "If the disposition is set to a function, then first either the disposition "
5376 "is reset to B<SIG_DFL>, or the signal is blocked (see I<Portability> below), "
5377 "and then I<handler> is called with argument I<signum>. If invocation of the "
5378 "handler caused the signal to be blocked, then the signal is unblocked upon "
5379 "return from the handler."
5383 #: build/C/man2/signal.2:97
5384 msgid "The signals B<SIGKILL> and B<SIGSTOP> cannot be caught or ignored."
5388 #: build/C/man2/signal.2:105
5390 "B<signal>() returns the previous value of the signal handler, or B<SIG_ERR> "
5391 "on error. In the event of an error, I<errno> is set to indicate the cause."
5395 #: build/C/man2/signal.2:110
5396 msgid "I<signum> is invalid."
5400 #: build/C/man2/signal.2:116
5401 msgid "The effects of B<signal>() in a multithreaded process are unspecified."
5405 #: build/C/man2/signal.2:141
5407 "See B<sigaction>(2) for details on what happens when B<SIGCHLD> is set to "
5412 #: build/C/man2/signal.2:146
5414 "See B<signal>(7) for a list of the async-signal-safe functions that can be "
5415 "safely called from inside a signal handler."
5418 #. libc4 and libc5 define
5419 #. .IR SignalHandler ;
5421 #: build/C/man2/signal.2:162
5423 "The use of I<sighandler_t> is a GNU extension, exposed if B<_GNU_SOURCE> is "
5424 "defined; glibc also defines (the BSD-derived) I<sig_t> if B<_BSD_SOURCE> is "
5425 "defined. Without use of such a type, the declaration of B<signal>() is the "
5426 "somewhat harder to read:"
5430 #: build/C/man2/signal.2:166
5433 "B<void ( *>I<signal>B<(int >I<signum>B<, void (*>I<handler>B<)(int)) ) "
5438 #: build/C/man2/signal.2:168
5444 #: build/C/man2/signal.2:180
5446 "The only portable use of B<signal>() is to set a signal's disposition to "
5447 "B<SIG_DFL> or B<SIG_IGN>. The semantics when using B<signal>() to "
5448 "establish a signal handler vary across systems (and POSIX.1 explicitly "
5449 "permits this variation); B<do not use it for this purpose.>"
5453 #: build/C/man2/signal.2:186
5455 "POSIX.1 solved the portability mess by specifying B<sigaction>(2), which "
5456 "provides explicit control of the semantics when a signal handler is invoked; "
5457 "use that interface instead of B<signal>()."
5461 #: build/C/man2/signal.2:196
5463 "In the original UNIX systems, when a handler that was established using "
5464 "B<signal>() was invoked by the delivery of a signal, the disposition of the "
5465 "signal would be reset to B<SIG_DFL>, and the system did not block delivery "
5466 "of further instances of the signal. This is equivalent to calling "
5467 "B<sigaction>(2) with the following flags:"
5471 #: build/C/man2/signal.2:198
5473 msgid " sa.sa_flags = SA_RESETHAND | SA_NODEFER;\n"
5477 #: build/C/man2/signal.2:205
5479 "System\\ V also provides these semantics for B<signal>(). This was bad "
5480 "because the signal might be delivered again before the handler had a chance "
5481 "to reestablish itself. Furthermore, rapid deliveries of the same signal "
5482 "could result in recursive invocations of the handler."
5486 #: build/C/man2/signal.2:220
5488 "BSD improved on this situation, but unfortunately also changed the semantics "
5489 "of the existing B<signal>() interface while doing so. On BSD, when a "
5490 "signal handler is invoked, the signal disposition is not reset, and further "
5491 "instances of the signal are blocked from being delivered while the handler "
5492 "is executing. Furthermore, certain blocking system calls are automatically "
5493 "restarted if interrupted by a signal handler (see B<signal>(7)). The BSD "
5494 "semantics are equivalent to calling B<sigaction>(2) with the following "
5499 #: build/C/man2/signal.2:222
5501 msgid " sa.sa_flags = SA_RESTART;\n"
5505 #: build/C/man2/signal.2:224
5506 msgid "The situation on Linux is as follows:"
5510 #: build/C/man2/signal.2:228
5511 msgid "The kernel's B<signal>() system call provides System\\ V semantics."
5515 #: build/C/man2/signal.2:244
5517 "By default, in glibc 2 and later, the B<signal>() wrapper function does not "
5518 "invoke the kernel system call. Instead, it calls B<sigaction>(2) using "
5519 "flags that supply BSD semantics. This default behavior is provided as long "
5520 "as the B<_BSD_SOURCE> feature test macro is defined. By default, "
5521 "B<_BSD_SOURCE> is defined; it is also implicitly defined if one defines "
5522 "B<_GNU_SOURCE>, and can of course be explicitly defined."
5526 #. System V semantics are also provided if one uses the separate
5527 #. .BR sysv_signal (3)
5530 #: build/C/man2/signal.2:267
5532 "On glibc 2 and later, if the B<_BSD_SOURCE> feature test macro is not "
5533 "defined, then B<signal>() provides System\\ V semantics. (The default "
5534 "implicit definition of B<_BSD_SOURCE> is not provided if one invokes "
5535 "B<gcc>(1) in one of its standard modes (I<-std=xxx> or I<-ansi>) or "
5536 "defines various other feature test macros such as B<_POSIX_SOURCE>, "
5537 "B<_XOPEN_SOURCE>, or B<_SVID_SOURCE>; see B<feature_test_macros>(7).)"
5541 #: build/C/man2/signal.2:278
5543 "The B<signal>() function in Linux libc4 and libc5 provide System\\ V "
5544 "semantics. If one on a libc5 system includes I<E<lt>bsd/signal.hE<gt>> "
5545 "instead of I<E<lt>signal.hE<gt>>, then B<signal>() provides BSD semantics."
5549 #: build/C/man2/signal.2:297
5551 "B<kill>(1), B<alarm>(2), B<kill>(2), B<killpg>(2), B<pause>(2), "
5552 "B<sigaction>(2), B<signalfd>(2), B<sigpending>(2), B<sigprocmask>(2), "
5553 "B<sigsuspend>(2), B<bsd_signal>(3), B<raise>(3), B<siginterrupt>(3), "
5554 "B<sigqueue>(3), B<sigsetops>(3), B<sigvec>(3), B<sysv_signal>(3), "
5559 #: build/C/man7/signal.7:46 build/C/man2/sigreturn.2:29
5565 #: build/C/man7/signal.7:49
5566 msgid "signal - overview of signals"
5570 #: build/C/man7/signal.7:52
5572 "Linux supports both POSIX reliable signals (hereinafter \"standard "
5573 "signals\") and POSIX real-time signals."
5577 #: build/C/man7/signal.7:52
5579 msgid "Signal dispositions"
5583 #: build/C/man7/signal.7:57
5585 "Each signal has a current I<disposition>, which determines how the process "
5586 "behaves when it is delivered the signal."
5590 #: build/C/man7/signal.7:60
5592 "The entries in the \"Action\" column of the tables below specify the default "
5593 "disposition for each signal, as follows:"
5597 #: build/C/man7/signal.7:60
5603 #: build/C/man7/signal.7:62
5604 msgid "Default action is to terminate the process."
5608 #: build/C/man7/signal.7:62
5614 #: build/C/man7/signal.7:64
5615 msgid "Default action is to ignore the signal."
5619 #: build/C/man7/signal.7:64
5625 #: build/C/man7/signal.7:67
5626 msgid "Default action is to terminate the process and dump core (see B<core>(5))."
5630 #: build/C/man7/signal.7:67
5636 #: build/C/man7/signal.7:69
5637 msgid "Default action is to stop the process."
5641 #: build/C/man7/signal.7:69
5647 #: build/C/man7/signal.7:71
5648 msgid "Default action is to continue the process if it is currently stopped."
5652 #: build/C/man7/signal.7:93
5654 "A process can change the disposition of a signal using B<sigaction>(2) or "
5655 "B<signal>(2). (The latter is less portable when establishing a signal "
5656 "handler; see B<signal>(2) for details.) Using these system calls, a "
5657 "process can elect one of the following behaviors to occur on delivery of the "
5658 "signal: perform the default action; ignore the signal; or catch the signal "
5659 "with a I<signal handler>, a programmer-defined function that is "
5660 "automatically invoked when the signal is delivered. (By default, the signal "
5661 "handler is invoked on the normal process stack. It is possible to arrange "
5662 "that the signal handler uses an alternate stack; see B<sigaltstack>(2) for "
5663 "a discussion of how to do this and when it might be useful.)"
5667 #: build/C/man7/signal.7:97
5669 "The signal disposition is a per-process attribute: in a multithreaded "
5670 "application, the disposition of a particular signal is the same for all "
5675 #: build/C/man7/signal.7:105
5677 msgid "Sending a signal"
5681 #: build/C/man7/signal.7:108
5683 "The following system calls and library functions allow the caller to send a "
5688 #: build/C/man7/signal.7:108
5694 #: build/C/man7/signal.7:111
5695 msgid "Sends a signal to the calling thread."
5699 #: build/C/man7/signal.7:116
5701 "Sends a signal to a specified process, to all members of a specified process "
5702 "group, or to all processes on the system."
5706 #: build/C/man7/signal.7:116
5708 msgid "B<killpg>(2)"
5712 #: build/C/man7/signal.7:119
5713 msgid "Sends a signal to all of the members of a specified process group."
5717 #: build/C/man7/signal.7:119
5719 msgid "B<pthread_kill>(3)"
5723 #: build/C/man7/signal.7:123
5725 "Sends a signal to a specified POSIX thread in the same process as the "
5730 #: build/C/man7/signal.7:123
5732 msgid "B<tgkill>(2)"
5736 #: build/C/man7/signal.7:128
5738 "Sends a signal to a specified thread within a specific process. (This is "
5739 "the system call used to implement B<pthread_kill>(3).)"
5743 #: build/C/man7/signal.7:131
5744 msgid "Sends a real-time signal with accompanying data to a specified process."
5748 #: build/C/man7/signal.7:131
5750 msgid "Waiting for a signal to be caught"
5754 #: build/C/man7/signal.7:135
5756 "The following system calls suspend execution of the calling process or "
5757 "thread until a signal is caught (or an unhandled signal terminates the "
5762 #: build/C/man7/signal.7:135
5768 #: build/C/man7/signal.7:138
5769 msgid "Suspends execution until any signal is caught."
5773 #: build/C/man7/signal.7:138
5775 msgid "B<sigsuspend>(2)"
5779 #: build/C/man7/signal.7:142
5781 "Temporarily changes the signal mask (see below) and suspends execution until "
5782 "one of the unmasked signals is caught."
5786 #: build/C/man7/signal.7:142
5788 msgid "Synchronously accepting a signal"
5792 #: build/C/man7/signal.7:149
5794 "Rather than asynchronously catching a signal via a signal handler, it is "
5795 "possible to synchronously accept the signal, that is, to block execution "
5796 "until the signal is delivered, at which point the kernel returns information "
5797 "about the signal to the caller. There are two general ways to do this:"
5801 #: build/C/man7/signal.7:157
5803 "B<sigwaitinfo>(2), B<sigtimedwait>(2), and B<sigwait>(3) suspend execution "
5804 "until one of the signals in a specified set is delivered. Each of these "
5805 "calls returns information about the delivered signal."
5809 #: build/C/man7/signal.7:170
5811 "B<signalfd>(2) returns a file descriptor that can be used to read "
5812 "information about signals that are delivered to the caller. Each B<read>(2) "
5813 "from this file descriptor blocks until one of the signals in the set "
5814 "specified in the B<signalfd>(2) call is delivered to the caller. The "
5815 "buffer returned by B<read>(2) contains a structure describing the signal."
5819 #: build/C/man7/signal.7:170
5821 msgid "Signal mask and pending signals"
5825 #: build/C/man7/signal.7:177
5827 "A signal may be I<blocked>, which means that it will not be delivered until "
5828 "it is later unblocked. Between the time when it is generated and when it is "
5829 "delivered a signal is said to be I<pending>."
5833 #: build/C/man7/signal.7:186
5835 "Each thread in a process has an independent I<signal mask>, which indicates "
5836 "the set of signals that the thread is currently blocking. A thread can "
5837 "manipulate its signal mask using B<pthread_sigmask>(3). In a traditional "
5838 "single-threaded application, B<sigprocmask>(2) can be used to manipulate "
5843 #: build/C/man7/signal.7:192 build/C/man2/sigprocmask.2:126
5845 "A child created via B<fork>(2) inherits a copy of its parent's signal mask; "
5846 "the signal mask is preserved across B<execve>(2)."
5850 #: build/C/man7/signal.7:209
5852 "A signal may be generated (and thus pending) for a process as a whole "
5853 "(e.g., when sent using B<kill>(2)) or for a specific thread (e.g., certain "
5854 "signals, such as B<SIGSEGV> and B<SIGFPE>, generated as a consequence of "
5855 "executing a specific machine-language instruction are thread directed, as "
5856 "are signals targeted at a specific thread using B<pthread_kill>(3)). A "
5857 "process-directed signal may be delivered to any one of the threads that does "
5858 "not currently have the signal blocked. If more than one of the threads has "
5859 "the signal unblocked, then the kernel chooses an arbitrary thread to which "
5860 "to deliver the signal."
5864 #: build/C/man7/signal.7:216
5866 "A thread can obtain the set of signals that it currently has pending using "
5867 "B<sigpending>(2). This set will consist of the union of the set of pending "
5868 "process-directed signals and the set of signals pending for the calling "
5873 #: build/C/man7/signal.7:222 build/C/man2/sigpending.2:85
5875 "A child created via B<fork>(2) initially has an empty pending signal set; "
5876 "the pending signal set is preserved across an B<execve>(2)."
5880 #: build/C/man7/signal.7:222
5882 msgid "Standard signals"
5886 #: build/C/man7/signal.7:234
5888 "Linux supports the standard signals listed below. Several signal numbers "
5889 "are architecture-dependent, as indicated in the \"Value\" column. (Where "
5890 "three values are given, the first one is usually valid for alpha and sparc, "
5891 "the middle one for x86, arm, and most other architectures, and the last one "
5892 "for mips. (Values for parisc are I<not> shown; see the Linux kernel source "
5893 "for signal numbering on that architecture.) A - denotes that a signal is "
5894 "absent on the corresponding architecture.)"
5898 #: build/C/man7/signal.7:236
5899 msgid "First the signals described in the original POSIX.1-1990 standard."
5903 #: build/C/man7/signal.7:240 build/C/man7/signal.7:276 build/C/man7/signal.7:305
5905 msgid "Signal\tValue\tAction\tComment\n"
5909 #: build/C/man7/signal.7:241
5911 msgid "SIGHUP\t\\01\tTerm\tHangup detected on controlling terminal\n"
5915 #: build/C/man7/signal.7:242
5917 msgid "\t\t\tor death of controlling process\n"
5921 #: build/C/man7/signal.7:243
5923 msgid "SIGINT\t\\02\tTerm\tInterrupt from keyboard\n"
5927 #: build/C/man7/signal.7:244
5929 msgid "SIGQUIT\t\\03\tCore\tQuit from keyboard\n"
5933 #: build/C/man7/signal.7:245
5935 msgid "SIGILL\t\\04\tCore\tIllegal Instruction\n"
5939 #: build/C/man7/signal.7:246
5941 msgid "SIGABRT\t\\06\tCore\tAbort signal from B<abort>(3)\n"
5945 #: build/C/man7/signal.7:247
5947 msgid "SIGFPE\t\\08\tCore\tFloating point exception\n"
5951 #: build/C/man7/signal.7:248
5953 msgid "SIGKILL\t\\09\tTerm\tKill signal\n"
5957 #: build/C/man7/signal.7:249
5959 msgid "SIGSEGV\t11\tCore\tInvalid memory reference\n"
5963 #: build/C/man7/signal.7:250
5965 msgid "SIGPIPE\t13\tTerm\tBroken pipe: write to pipe with no\n"
5969 #: build/C/man7/signal.7:251
5971 msgid "\t\t\treaders\n"
5975 #: build/C/man7/signal.7:252
5977 msgid "SIGALRM\t14\tTerm\tTimer signal from B<alarm>(2)\n"
5981 #: build/C/man7/signal.7:253
5983 msgid "SIGTERM\t15\tTerm\tTermination signal\n"
5987 #: build/C/man7/signal.7:254
5989 msgid "SIGUSR1\t30,10,16\tTerm\tUser-defined signal 1\n"
5993 #: build/C/man7/signal.7:255
5995 msgid "SIGUSR2\t31,12,17\tTerm\tUser-defined signal 2\n"
5999 #: build/C/man7/signal.7:256
6001 msgid "SIGCHLD\t20,17,18\tIgn\tChild stopped or terminated\n"
6005 #: build/C/man7/signal.7:257
6007 msgid "SIGCONT\t19,18,25\tCont\tContinue if stopped\n"
6011 #: build/C/man7/signal.7:258
6013 msgid "SIGSTOP\t17,19,23\tStop\tStop process\n"
6017 #: build/C/man7/signal.7:259
6019 msgid "SIGTSTP\t18,20,24\tStop\tStop typed at terminal\n"
6023 #: build/C/man7/signal.7:260
6025 msgid "SIGTTIN\t21,21,26\tStop\tTerminal input for background process\n"
6029 #: build/C/man7/signal.7:261
6031 msgid "SIGTTOU\t22,22,27\tStop\tTerminal output for background process\n"
6035 #: build/C/man7/signal.7:269
6036 msgid "The signals B<SIGKILL> and B<SIGSTOP> cannot be caught, blocked, or ignored."
6040 #: build/C/man7/signal.7:272
6042 "Next the signals not in the POSIX.1-1990 standard but described in SUSv2 and "
6047 #: build/C/man7/signal.7:277
6049 msgid "SIGBUS\t10,7,10\tCore\tBus error (bad memory access)\n"
6053 #: build/C/man7/signal.7:278
6055 msgid "SIGPOLL\t\tTerm\tPollable event (Sys V).\n"
6059 #: build/C/man7/signal.7:279
6061 msgid "\t\t\tSynonym for B<SIGIO>\n"
6065 #: build/C/man7/signal.7:280
6067 msgid "SIGPROF\t27,27,29\tTerm\tProfiling timer expired\n"
6071 #: build/C/man7/signal.7:281
6073 msgid "SIGSYS\t12,31,12\tCore\tBad argument to routine (SVr4)\n"
6077 #: build/C/man7/signal.7:282
6079 msgid "SIGTRAP\t5\tCore\tTrace/breakpoint trap\n"
6083 #: build/C/man7/signal.7:283
6085 msgid "SIGURG\t16,23,21\tIgn\tUrgent condition on socket (4.2BSD)\n"
6089 #: build/C/man7/signal.7:284
6091 msgid "SIGVTALRM\t26,26,28\tTerm\tVirtual alarm clock (4.2BSD)\n"
6095 #: build/C/man7/signal.7:285
6097 msgid "SIGXCPU\t24,24,30\tCore\tCPU time limit exceeded (4.2BSD)\n"
6101 #: build/C/man7/signal.7:286
6103 msgid "SIGXFSZ\t25,25,31\tCore\tFile size limit exceeded (4.2BSD)\n"
6107 #: build/C/man7/signal.7:299
6109 "Up to and including Linux 2.2, the default behavior for B<SIGSYS>, "
6110 "B<SIGXCPU>, B<SIGXFSZ>, and (on architectures other than SPARC and MIPS) "
6111 "B<SIGBUS> was to terminate the process (without a core dump). (On some "
6112 "other UNIX systems the default action for B<SIGXCPU> and B<SIGXFSZ> is to "
6113 "terminate the process without a core dump.) Linux 2.4 conforms to the "
6114 "POSIX.1-2001 requirements for these signals, terminating the process with a "
6119 #: build/C/man7/signal.7:301
6120 msgid "Next various other signals."
6124 #: build/C/man7/signal.7:306
6126 msgid "SIGIOT\t6\tCore\tIOT trap. A synonym for B<SIGABRT>\n"
6130 #: build/C/man7/signal.7:307
6132 msgid "SIGEMT\t7,-,7\tTerm\n"
6136 #: build/C/man7/signal.7:308
6138 msgid "SIGSTKFLT\t-,16,-\tTerm\tStack fault on coprocessor (unused)\n"
6142 #: build/C/man7/signal.7:309
6144 msgid "SIGIO\t23,29,22\tTerm\tI/O now possible (4.2BSD)\n"
6148 #: build/C/man7/signal.7:310
6150 msgid "SIGCLD\t-,-,18\tIgn\tA synonym for B<SIGCHLD>\n"
6154 #: build/C/man7/signal.7:311
6156 msgid "SIGPWR\t29,30,19\tTerm\tPower failure (System V)\n"
6160 #: build/C/man7/signal.7:312
6162 msgid "SIGINFO\t29,-,-\t\tA synonym for B<SIGPWR>\n"
6166 #: build/C/man7/signal.7:313
6168 msgid "SIGLOST\t-,-,-\tTerm\tFile lock lost (unused)\n"
6172 #: build/C/man7/signal.7:314
6174 msgid "SIGWINCH\t28,28,20\tIgn\tWindow resize signal (4.3BSD, Sun)\n"
6178 #: build/C/man7/signal.7:315
6180 msgid "SIGUNUSED\t-,31,-\tCore\tSynonymous with B<SIGSYS>\n"
6184 #: build/C/man7/signal.7:325
6185 msgid "(Signal 29 is B<SIGINFO> / B<SIGPWR> on an alpha but B<SIGLOST> on a sparc.)"
6189 #: build/C/man7/signal.7:331
6191 "B<SIGEMT> is not specified in POSIX.1-2001, but nevertheless appears on most "
6192 "other UNIX systems, where its default action is typically to terminate the "
6193 "process with a core dump."
6197 #: build/C/man7/signal.7:335
6199 "B<SIGPWR> (which is not specified in POSIX.1-2001) is typically ignored by "
6200 "default on those other UNIX systems where it appears."
6204 #: build/C/man7/signal.7:339
6206 "B<SIGIO> (which is not specified in POSIX.1-2001) is ignored by default on "
6207 "several other UNIX systems."
6210 #. parisc is the only exception: SIGSYS is 12, SIGUNUSED is 31
6212 #: build/C/man7/signal.7:346
6214 "Where defined, B<SIGUNUSED> is synonymous with B<SIGSYS> on most "
6219 #: build/C/man7/signal.7:346
6221 msgid "Real-time signals"
6225 #: build/C/man7/signal.7:356
6227 "Linux supports real-time signals as originally defined in the POSIX.1b "
6228 "real-time extensions (and now included in POSIX.1-2001). The range of "
6229 "supported real-time signals is defined by the macros B<SIGRTMIN> and "
6230 "B<SIGRTMAX>. POSIX.1-2001 requires that an implementation support at least "
6231 "B<_POSIX_RTSIG_MAX> (8) real-time signals."
6235 #: build/C/man7/signal.7:378
6237 "The Linux kernel supports a range of 32 different real-time signals, "
6238 "numbered 33 to 64. However, the glibc POSIX threads implementation "
6239 "internally uses two (for NPTL) or three (for LinuxThreads) real-time signals "
6240 "(see B<pthreads>(7)), and adjusts the value of B<SIGRTMIN> suitably (to 34 "
6241 "or 35). Because the range of available real-time signals varies according "
6242 "to the glibc threading implementation (and this variation can occur at run "
6243 "time according to the available kernel and glibc), and indeed the range of "
6244 "real-time signals varies across UNIX systems, programs should I<never refer "
6245 "to real-time signals using hard-coded numbers>, but instead should always "
6246 "refer to real-time signals using the notation B<SIGRTMIN>+n, and include "
6247 "suitable (run-time) checks that B<SIGRTMIN>+n does not exceed B<SIGRTMAX>."
6251 #: build/C/man7/signal.7:382
6253 "Unlike standard signals, real-time signals have no predefined meanings: the "
6254 "entire set of real-time signals can be used for application-defined "
6259 #: build/C/man7/signal.7:385
6261 "The default action for an unhandled real-time signal is to terminate the "
6262 "receiving process."
6266 #: build/C/man7/signal.7:387
6267 msgid "Real-time signals are distinguished by the following:"
6271 #: build/C/man7/signal.7:391
6273 "Multiple instances of real-time signals can be queued. By contrast, if "
6274 "multiple instances of a standard signal are delivered while that signal is "
6275 "currently blocked, then only one instance is queued."
6279 #: build/C/man7/signal.7:411
6281 "If the signal is sent using B<sigqueue>(3), an accompanying value (either an "
6282 "integer or a pointer) can be sent with the signal. If the receiving process "
6283 "establishes a handler for this signal using the B<SA_SIGINFO> flag to "
6284 "B<sigaction>(2), then it can obtain this data via the I<si_value> field of "
6285 "the I<siginfo_t> structure passed as the second argument to the handler. "
6286 "Furthermore, the I<si_pid> and I<si_uid> fields of this structure can be "
6287 "used to obtain the PID and real user ID of the process sending the signal."
6291 #: build/C/man7/signal.7:420
6293 "Real-time signals are delivered in a guaranteed order. Multiple real-time "
6294 "signals of the same type are delivered in the order they were sent. If "
6295 "different real-time signals are sent to a process, they are delivered "
6296 "starting with the lowest-numbered signal. (I.e., low-numbered signals have "
6297 "highest priority.) By contrast, if multiple standard signals are pending "
6298 "for a process, the order in which they are delivered is unspecified."
6302 #: build/C/man7/signal.7:425
6304 "If both standard and real-time signals are pending for a process, POSIX "
6305 "leaves it unspecified which is delivered first. Linux, like many other "
6306 "implementations, gives priority to standard signals in this case."
6310 #: build/C/man7/signal.7:448
6312 "According to POSIX, an implementation should permit at least "
6313 "B<_POSIX_SIGQUEUE_MAX> (32) real-time signals to be queued to a process. "
6314 "However, Linux does things differently. In kernels up to and including "
6315 "2.6.7, Linux imposes a system-wide limit on the number of queued real-time "
6316 "signals for all processes. This limit can be viewed and (with privilege) "
6317 "changed via the I</proc/sys/kernel/rtsig-max> file. A related file, "
6318 "I</proc/sys/kernel/rtsig-nr>, can be used to find out how many real-time "
6319 "signals are currently queued. In Linux 2.6.8, these I</proc> interfaces "
6320 "were replaced by the B<RLIMIT_SIGPENDING> resource limit, which specifies a "
6321 "per-user limit for queued signals; see B<setrlimit>(2) for further details."
6325 #: build/C/man7/signal.7:448
6327 msgid "Async-signal-safe functions"
6331 #: build/C/man7/signal.7:457
6333 "A signal handler function must be very careful, since processing elsewhere "
6334 "may be interrupted at some arbitrary point in the execution of the program. "
6335 "POSIX has the concept of \"safe function\". If a signal interrupts the "
6336 "execution of an unsafe function, and I<handler> calls an unsafe function, "
6337 "then the behavior of the program is undefined."
6341 #: build/C/man7/signal.7:461
6343 "POSIX.1-2004 (also known as POSIX.1-2001 Technical Corrigendum 2) requires "
6344 "an implementation to guarantee that the following functions can be safely "
6345 "called inside a signal handler:"
6349 #: build/C/man7/signal.7:582
6409 "posix_trace_event()\n"
6459 "timer_getoverrun()\n"
6473 #: build/C/man7/signal.7:587
6475 "POSIX.1-2008 removes fpathconf(), pathconf(), and sysconf() from the above "
6476 "list, and adds the following functions:"
6480 #: build/C/man7/signal.7:610
6506 #: build/C/man7/signal.7:612
6508 msgid "Interruption of system calls and library functions by signal handlers"
6512 #: build/C/man7/signal.7:615
6514 "If a signal handler is invoked while a system call or library function call "
6515 "is blocked, then either:"
6519 #: build/C/man7/signal.7:617
6520 msgid "the call is automatically restarted after the signal handler returns; or"
6524 #: build/C/man7/signal.7:620
6525 msgid "the call fails with the error B<EINTR>."
6529 #: build/C/man7/signal.7:628
6531 "Which of these two behaviors occurs depends on the interface and whether or "
6532 "not the signal handler was established using the B<SA_RESTART> flag (see "
6533 "B<sigaction>(2)). The details vary across UNIX systems; below, the details "
6537 #. The following system calls use ERESTARTSYS,
6538 #. so that they are restartable
6540 #: build/C/man7/signal.7:637
6542 "If a blocked call to one of the following interfaces is interrupted by a "
6543 "signal handler, then the call will be automatically restarted after the "
6544 "signal handler returns if the B<SA_RESTART> flag was used; otherwise the "
6545 "call will fail with the error B<EINTR>:"
6549 #: build/C/man7/signal.7:653
6551 "B<read>(2), B<readv>(2), B<write>(2), B<writev>(2), and B<ioctl>(2) calls "
6552 "on \"slow\" devices. A \"slow\" device is one where the I/O call may block "
6553 "for an indefinite time, for example, a terminal, pipe, or socket. (A disk "
6554 "is not a slow device according to this definition.) If an I/O call on a "
6555 "slow device has already transferred some data by the time it is interrupted "
6556 "by a signal handler, then the call will return a success status (normally, "
6557 "the number of bytes transferred)."
6561 #: build/C/man7/signal.7:657
6562 msgid "B<open>(2), if it can block (e.g., when opening a FIFO; see B<fifo>(7))."
6566 #: build/C/man7/signal.7:664
6567 msgid "B<wait>(2), B<wait3>(2), B<wait4>(2), B<waitid>(2), and B<waitpid>(2)."
6570 #. If a timeout (setsockopt()) is in effect on the socket, then these
6571 #. system calls switch to using EINTR. Consequently, they and are not
6572 #. automatically restarted, and they show the stop/cont behavior
6573 #. described below. (Verified from 2.6.26 source, and by experiment; mtk)
6575 #: build/C/man7/signal.7:680
6577 "Socket interfaces: B<accept>(2), B<connect>(2), B<recv>(2), B<recvfrom>(2), "
6578 "B<recvmsg>(2), B<send>(2), B<sendto>(2), and B<sendmsg>(2), unless a timeout "
6579 "has been set on the socket (see below)."
6583 #: build/C/man7/signal.7:686
6584 msgid "File locking interfaces: B<flock>(2) and B<fcntl>(2) B<F_SETLKW>."
6588 #: build/C/man7/signal.7:693
6590 "POSIX message queue interfaces: B<mq_receive>(3), B<mq_timedreceive>(3), "
6591 "B<mq_send>(3), and B<mq_timedsend>(3)."
6595 #: build/C/man7/signal.7:698
6597 "B<futex>(2) B<FUTEX_WAIT> (since Linux 2.6.22; beforehand, always failed "
6602 #: build/C/man7/signal.7:705
6604 "POSIX semaphore interfaces: B<sem_wait>(3) and B<sem_timedwait>(3) (since "
6605 "Linux 2.6.22; beforehand, always failed with B<EINTR>)."
6608 #. These are the system calls that give EINTR or ERESTARTNOHAND
6609 #. on interruption by a signal handler.
6611 #: build/C/man7/signal.7:716
6613 "The following interfaces are never restarted after being interrupted by a "
6614 "signal handler, regardless of the use of B<SA_RESTART>; they always fail "
6615 "with the error B<EINTR> when interrupted by a signal handler:"
6619 #: build/C/man7/signal.7:736 build/C/man7/signal.7:810
6621 "Socket interfaces, when a timeout has been set on the socket using "
6622 "B<setsockopt>(2): B<accept>(2), B<recv>(2), B<recvfrom>(2), and "
6623 "B<recvmsg>(2), if a receive timeout (B<SO_RCVTIMEO>) has been set; "
6624 "B<connect>(2), B<send>(2), B<sendto>(2), and B<sendmsg>(2), if a send "
6625 "timeout (B<SO_SNDTIMEO>) has been set."
6629 #: build/C/man7/signal.7:743
6631 "Interfaces used to wait for signals: B<pause>(2), B<sigsuspend>(2), "
6632 "B<sigtimedwait>(2), and B<sigwaitinfo>(2)."
6636 #: build/C/man7/signal.7:752
6638 "File descriptor multiplexing interfaces: B<epoll_wait>(2), "
6639 "B<epoll_pwait>(2), B<poll>(2), B<ppoll>(2), B<select>(2), and B<pselect>(2)."
6642 #. On some other systems, SA_RESTART does restart these system calls
6644 #: build/C/man7/signal.7:760
6646 "System V IPC interfaces: B<msgrcv>(2), B<msgsnd>(2), B<semop>(2), and "
6651 #: build/C/man7/signal.7:766
6652 msgid "Sleep interfaces: B<clock_nanosleep>(2), B<nanosleep>(2), and B<usleep>(3)."
6656 #: build/C/man7/signal.7:771 build/C/man7/signal.7:824
6657 msgid "B<read>(2) from an B<inotify>(7) file descriptor."
6661 #: build/C/man7/signal.7:773
6662 msgid "B<io_getevents>(2)."
6666 #: build/C/man7/signal.7:779
6668 "The B<sleep>(3) function is also never restarted if interrupted by a "
6669 "handler, but gives a success return: the number of seconds remaining to "
6674 #: build/C/man7/signal.7:779
6676 msgid "Interruption of system calls and library functions by stop signals"
6680 #: build/C/man7/signal.7:788
6682 "On Linux, even in the absence of signal handlers, certain blocking "
6683 "interfaces can fail with the error B<EINTR> after the process is stopped by "
6684 "one of the stop signals and then resumed via B<SIGCONT>. This behavior is "
6685 "not sanctioned by POSIX.1, and doesn't occur on other systems."
6689 #: build/C/man7/signal.7:790
6690 msgid "The Linux interfaces that display this behavior are:"
6694 #: build/C/man7/signal.7:813
6695 msgid "B<epoll_wait>(2), B<epoll_pwait>(2)."
6699 #: build/C/man7/signal.7:816
6700 msgid "B<semop>(2), B<semtimedop>(2)."
6704 #: build/C/man7/signal.7:819
6705 msgid "B<sigtimedwait>(2), B<sigwaitinfo>(2)."
6709 #: build/C/man7/signal.7:830
6711 "Linux 2.6.21 and earlier: B<futex>(2) B<FUTEX_WAIT>, B<sem_timedwait>(3), "
6716 #: build/C/man7/signal.7:834
6717 msgid "Linux 2.6.8 and earlier: B<msgrcv>(2), B<msgsnd>(2)."
6721 #: build/C/man7/signal.7:837
6722 msgid "Linux 2.4 and earlier: B<nanosleep>(2)."
6725 #. It must be a *very* long time since this was true:
6730 #. have the same value.
6731 #. The latter is commented out in the kernel source, but
6732 #. the build process of some software still thinks that
6736 #: build/C/man7/signal.7:850
6737 msgid "POSIX.1, except as noted."
6741 #: build/C/man7/signal.7:884
6743 "B<kill>(1), B<getrlimit>(2), B<kill>(2), B<killpg>(2), "
6744 "B<restart_syscall>(2), B<rt_sigqueueinfo>(2), B<setitimer>(2), "
6745 "B<setrlimit>(2), B<sgetmask>(2), B<sigaction>(2), B<sigaltstack>(2), "
6746 "B<signal>(2), B<signalfd>(2), B<sigpending>(2), B<sigprocmask>(2), "
6747 "B<sigsuspend>(2), B<sigwaitinfo>(2), B<abort>(3), B<bsd_signal>(3), "
6748 "B<longjmp>(3), B<raise>(3), B<pthread_sigqueue>(3), B<sigqueue>(3), "
6749 "B<sigset>(3), B<sigsetops>(3), B<sigvec>(3), B<sigwait>(3), B<strsignal>(3), "
6750 "B<sysv_signal>(3), B<core>(5), B<proc>(5), B<pthreads>(7), B<sigevent>(7)"
6754 #: build/C/man2/signalfd.2:20
6760 #: build/C/man2/signalfd.2:20
6766 #: build/C/man2/signalfd.2:23
6767 msgid "signalfd - create a file descriptor for accepting signals"
6771 #: build/C/man2/signalfd.2:25
6772 msgid "B<#include E<lt>sys/signalfd.hE<gt>>"
6776 #: build/C/man2/signalfd.2:27
6777 msgid "B<int signalfd(int >I<fd>B<, const sigset_t *>I<mask>B<, int >I<flags>B<);>"
6781 #: build/C/man2/signalfd.2:38
6783 "B<signalfd>() creates a file descriptor that can be used to accept signals "
6784 "targeted at the caller. This provides an alternative to the use of a signal "
6785 "handler or B<sigwaitinfo>(2), and has the advantage that the file descriptor "
6786 "may be monitored by B<select>(2), B<poll>(2), and B<epoll>(7)."
6790 #: build/C/man2/signalfd.2:58
6792 "The I<mask> argument specifies the set of signals that the caller wishes to "
6793 "accept via the file descriptor. This argument is a signal set whose "
6794 "contents can be initialized using the macros described in B<sigsetops>(3). "
6795 "Normally, the set of signals to be received via the file descriptor should "
6796 "be blocked using B<sigprocmask>(2), to prevent the signals being handled "
6797 "according to their default dispositions. It is not possible to receive "
6798 "B<SIGKILL> or B<SIGSTOP> signals via a signalfd file descriptor; these "
6799 "signals are silently ignored if specified in I<mask>."
6803 #: build/C/man2/signalfd.2:72
6805 "If the I<fd> argument is -1, then the call creates a new file descriptor and "
6806 "associates the signal set specified in I<mask> with that descriptor. If "
6807 "I<fd> is not -1, then it must specify a valid existing signalfd file "
6808 "descriptor, and I<mask> is used to replace the signal set associated with "
6813 #: build/C/man2/signalfd.2:77
6815 "Starting with Linux 2.6.27, the following values may be bitwise ORed in "
6816 "I<flags> to change the behaviour of B<signalfd>():"
6820 #: build/C/man2/signalfd.2:77
6822 msgid "B<SFD_NONBLOCK>"
6826 #: build/C/man2/signalfd.2:85
6828 msgid "B<SFD_CLOEXEC>"
6832 #: build/C/man2/signalfd.2:102
6834 "B<signalfd>() returns a file descriptor that supports the following "
6839 #: build/C/man2/signalfd.2:121
6841 "If one or more of the signals specified in I<mask> is pending for the "
6842 "process, then the buffer supplied to B<read>(2) is used to return one or "
6843 "more I<signalfd_siginfo> structures (see below) that describe the signals. "
6844 "The B<read>(2) returns information for as many signals as are pending and "
6845 "will fit in the supplied buffer. The buffer must be at least "
6846 "I<sizeof(struct signalfd_siginfo)> bytes. The return value of the "
6847 "B<read>(2) is the total number of bytes read."
6851 #: build/C/man2/signalfd.2:129
6853 "As a consequence of the B<read>(2), the signals are consumed, so that they "
6854 "are no longer pending for the process (i.e., will not be caught by signal "
6855 "handlers, and cannot be accepted using B<sigwaitinfo>(2))."
6859 #: build/C/man2/signalfd.2:140
6861 "If none of the signals in I<mask> is pending for the process, then the "
6862 "B<read>(2) either blocks until one of the signals in I<mask> is generated "
6863 "for the process, or fails with the error B<EAGAIN> if the file descriptor "
6864 "has been made nonblocking."
6868 #: build/C/man2/signalfd.2:153
6870 "The file descriptor is readable (the B<select>(2) I<readfds> argument; the "
6871 "B<poll>(2) B<POLLIN> flag) if one or more of the signals in I<mask> is "
6872 "pending for the process."
6876 #: build/C/man2/signalfd.2:160
6878 "The signalfd file descriptor also supports the other file-descriptor "
6879 "multiplexing APIs: B<pselect>(2), B<ppoll>(2), and B<epoll>(7)."
6883 #: build/C/man2/signalfd.2:165
6885 "When the file descriptor is no longer required it should be closed. When "
6886 "all file descriptors associated with the same signalfd object have been "
6887 "closed, the resources for object are freed by the kernel."
6891 #: build/C/man2/signalfd.2:165
6893 msgid "The signalfd_siginfo structure"
6897 #: build/C/man2/signalfd.2:171
6899 "The format of the I<signalfd_siginfo> structure(s) returned by B<read>(2)s "
6900 "from a signalfd file descriptor is as follows:"
6903 #. ssi_trapno is unused on most arches
6904 #. FIXME Since Linux 2.6.37 there is 'uint16_t ssi_addr_lsb'
6905 #. which is not yet documented
6907 #: build/C/man2/signalfd.2:198
6910 "struct signalfd_siginfo {\n"
6911 " uint32_t ssi_signo; /* Signal number */\n"
6912 " int32_t ssi_errno; /* Error number (unused) */\n"
6913 " int32_t ssi_code; /* Signal code */\n"
6914 " uint32_t ssi_pid; /* PID of sender */\n"
6915 " uint32_t ssi_uid; /* Real UID of sender */\n"
6916 " int32_t ssi_fd; /* File descriptor (SIGIO) */\n"
6917 " uint32_t ssi_tid; /* Kernel timer ID (POSIX timers)\n"
6918 " uint32_t ssi_band; /* Band event (SIGIO) */\n"
6919 " uint32_t ssi_overrun; /* POSIX timer overrun count */\n"
6920 " uint32_t ssi_trapno; /* Trap number that caused signal */\n"
6921 " int32_t ssi_status; /* Exit status or signal (SIGCHLD) */\n"
6922 " int32_t ssi_int; /* Integer sent by sigqueue(3) */\n"
6923 " uint64_t ssi_ptr; /* Pointer sent by sigqueue(3) */\n"
6924 " uint64_t ssi_utime; /* User CPU time consumed (SIGCHLD) */\n"
6925 " uint64_t ssi_stime; /* System CPU time consumed (SIGCHLD) */\n"
6926 " uint64_t ssi_addr; /* Address that generated signal\n"
6927 " (for hardware-generated signals) */\n"
6928 " uint8_t pad[I<X>]; /* Pad size to 128 bytes (allow for\n"
6929 " additional fields in the future) */\n"
6934 #: build/C/man2/signalfd.2:221
6936 "Each of the fields in this structure is analogous to the similarly named "
6937 "field in the I<siginfo_t> structure. The I<siginfo_t> structure is "
6938 "described in B<sigaction>(2). Not all fields in the returned "
6939 "I<signalfd_siginfo> structure will be valid for a specific signal; the set "
6940 "of valid fields can be determined from the value returned in the I<ssi_code> "
6941 "field. This field is the analog of the I<siginfo_t> I<si_code> field; see "
6942 "B<sigaction>(2) for details."
6946 #: build/C/man2/signalfd.2:221 build/C/man2/timerfd_create.2:269
6948 msgid "fork(2) semantics"
6952 #: build/C/man2/signalfd.2:229
6954 "After a B<fork>(2), the child inherits a copy of the signalfd file "
6955 "descriptor. A B<read>(2) from the file descriptor in the child will return "
6956 "information about signals queued to the child."
6960 #: build/C/man2/signalfd.2:229 build/C/man2/timerfd_create.2:281
6962 msgid "execve(2) semantics"
6966 #: build/C/man2/signalfd.2:241
6968 "Just like any other file descriptor, a signalfd file descriptor remains open "
6969 "across an B<execve>(2), unless it has been marked for close-on-exec (see "
6970 "B<fcntl>(2)). Any signals that were available for reading before the "
6971 "B<execve>(2) remain available to the newly loaded program. (This is "
6972 "analogous to traditional signal semantics, where a blocked signal that is "
6973 "pending remains pending across an B<execve>(2).)"
6977 #: build/C/man2/signalfd.2:241
6979 msgid "Thread semantics"
6983 #: build/C/man2/signalfd.2:251
6985 "The semantics of signalfd file descriptors in a multithreaded program mirror "
6986 "the standard semantics for signals. In other words, when a thread reads "
6987 "from a signalfd file descriptor, it will read the signals that are directed "
6988 "to the thread itself and the signals that are directed to the process (i.e., "
6989 "the entire thread group). (A thread will not be able to read signals that "
6990 "are directed to other threads in the process.)"
6994 #: build/C/man2/signalfd.2:265
6996 "On success, B<signalfd>() returns a signalfd file descriptor; this is "
6997 "either a new file descriptor (if I<fd> was -1), or I<fd> if I<fd> was a "
6998 "valid signalfd file descriptor. On error, -1 is returned and I<errno> is "
6999 "set to indicate the error."
7003 #: build/C/man2/signalfd.2:271
7004 msgid "The I<fd> file descriptor is not a valid file descriptor."
7009 #. argument is not equal to
7010 #. .IR sizeof(sigset_t) ;
7012 #: build/C/man2/signalfd.2:279
7013 msgid "I<fd> is not a valid signalfd file descriptor."
7017 #: build/C/man2/signalfd.2:286 build/C/man2/timerfd_create.2:320
7018 msgid "I<flags> is invalid; or, in Linux 2.6.26 or earlier, I<flags> is nonzero."
7022 #: build/C/man2/signalfd.2:289 build/C/man2/timerfd_create.2:323
7023 msgid "The per-process limit of open file descriptors has been reached."
7027 #: build/C/man2/signalfd.2:299
7028 msgid "There was insufficient memory to create a new signalfd file descriptor."
7031 #. signalfd() is in glibc 2.7, but reportedly does not build
7033 #: build/C/man2/signalfd.2:307
7035 "B<signalfd>() is available on Linux since kernel 2.6.22. Working support "
7036 "is provided in glibc since version 2.8. The B<signalfd4>() system call "
7037 "(see NOTES) is available on Linux since kernel 2.6.27."
7041 #: build/C/man2/signalfd.2:312
7042 msgid "B<signalfd>() and B<signalfd4>() are Linux-specific."
7046 #: build/C/man2/signalfd.2:322
7048 "The underlying Linux system call requires an additional argument, I<size_t "
7049 "sizemask>, which specifies the size of the I<mask> argument. The glibc "
7050 "B<signalfd>() wrapper function does not include this argument, since it "
7051 "provides the required value for the underlying system call."
7055 #: build/C/man2/signalfd.2:336
7057 "A process can create multiple signalfd file descriptors. This makes it "
7058 "possible to accept different signals on different file descriptors. (This "
7059 "may be useful if monitoring the file descriptors using B<select>(2), "
7060 "B<poll>(2), or B<epoll>(7): the arrival of different signals will make "
7061 "different descriptors ready.) If a signal appears in the I<mask> of more "
7062 "than one of the file descriptors, then occurrences of that signal can be "
7063 "read (once) from any one of the descriptors."
7067 #: build/C/man2/signalfd.2:352
7069 "There are two underlying Linux system calls: B<signalfd>() and the more "
7070 "recent B<signalfd4>(). The former system call does not implement a I<flags> "
7071 "argument. The latter system call implements the I<flags> values described "
7072 "above. Starting with glibc 2.9, the B<signalfd>() wrapper function will "
7073 "use B<signalfd4>() where it is available."
7076 #. The fix also was put into 2.6.24.5
7078 #: build/C/man2/signalfd.2:360
7080 "In kernels before 2.6.25, the I<ssi_ptr> and I<ssi_int> fields are not "
7081 "filled in with the data accompanying a signal sent by B<sigqueue>(3)."
7085 #: build/C/man2/signalfd.2:370
7087 "The program below accepts the signals B<SIGINT> and B<SIGQUIT> via a "
7088 "signalfd file descriptor. The program terminates after accepting a "
7089 "B<SIGQUIT> signal. The following shell session demonstrates the use of the "
7094 #: build/C/man2/signalfd.2:381
7097 "$B< ./signalfd_demo>\n"
7098 "B<^C> # Control-C generates SIGINT\n"
7102 "B<^\\e> # Control-\\e generates SIGQUIT\n"
7108 #: build/C/man2/signalfd.2:391
7111 "#include E<lt>sys/signalfd.hE<gt>\n"
7112 "#include E<lt>signal.hE<gt>\n"
7113 "#include E<lt>unistd.hE<gt>\n"
7114 "#include E<lt>stdlib.hE<gt>\n"
7115 "#include E<lt>stdio.hE<gt>\n"
7119 #: build/C/man2/signalfd.2:402
7123 "main(int argc, char *argv[])\n"
7127 " struct signalfd_siginfo fdsi;\n"
7132 #: build/C/man2/signalfd.2:406
7135 " sigemptyset(&mask);\n"
7136 " sigaddset(&mask, SIGINT);\n"
7137 " sigaddset(&mask, SIGQUIT);\n"
7141 #: build/C/man2/signalfd.2:409
7144 " /* Block signals so that they aren\\(aqt handled\n"
7145 " according to their default dispositions */\n"
7149 #: build/C/man2/signalfd.2:412
7152 " if (sigprocmask(SIG_BLOCK, &mask, NULL) == -1)\n"
7153 " handle_error(\"sigprocmask\");\n"
7157 #: build/C/man2/signalfd.2:416
7160 " sfd = signalfd(-1, &mask, 0);\n"
7162 " handle_error(\"signalfd\");\n"
7166 #: build/C/man2/signalfd.2:421
7170 " s = read(sfd, &fdsi, sizeof(struct signalfd_siginfo));\n"
7171 " if (s != sizeof(struct signalfd_siginfo))\n"
7172 " handle_error(\"read\");\n"
7176 #: build/C/man2/signalfd.2:432
7179 " if (fdsi.ssi_signo == SIGINT) {\n"
7180 " printf(\"Got SIGINT\\en\");\n"
7181 " } else if (fdsi.ssi_signo == SIGQUIT) {\n"
7182 " printf(\"Got SIGQUIT\\en\");\n"
7183 " exit(EXIT_SUCCESS);\n"
7185 " printf(\"Read unexpected signal\\en\");\n"
7192 #: build/C/man2/signalfd.2:446
7194 "B<eventfd>(2), B<poll>(2), B<read>(2), B<select>(2), B<sigaction>(2), "
7195 "B<sigprocmask>(2), B<sigwaitinfo>(2), B<timerfd_create>(2), B<sigsetops>(3), "
7196 "B<sigwait>(3), B<epoll>(7), B<signal>(7)"
7200 #: build/C/man3/sigpause.3:25
7206 #: build/C/man3/sigpause.3:25
7212 #: build/C/man3/sigpause.3:28
7213 msgid "sigpause - atomically release blocked signals and wait for interrupt"
7217 #: build/C/man3/sigpause.3:33
7219 msgid "B<int sigpause(int >I<sigmask>B<); /* BSD (but see NOTES) */>\n"
7223 #: build/C/man3/sigpause.3:35
7225 msgid "B<int sigpause(int >I<sig>B<); /* System V / UNIX 95 */>\n"
7229 #: build/C/man3/sigpause.3:41
7230 msgid "Don't use this function. Use B<sigsuspend>(2) instead."
7234 #: build/C/man3/sigpause.3:48
7236 "The function B<sigpause>() is designed to wait for some signal. It changes "
7237 "the process's signal mask (set of blocked signals), and then waits for a "
7238 "signal to arrive. Upon arrival of a signal, the original signal mask is "
7243 #: build/C/man3/sigpause.3:56
7245 "If B<sigpause>() returns, it was interrupted by a signal and the return "
7246 "value is -1 with I<errno> set to B<EINTR>."
7250 #: build/C/man3/sigpause.3:61
7251 msgid "The B<sigpause>() function is thread-safe."
7255 #: build/C/man3/sigpause.3:65
7256 msgid "The System V version of B<sigpause>() is standardized in POSIX.1-2001."
7259 #. __xpg_sigpause: UNIX 95, spec 1170, SVID, SVr4, XPG
7261 #: build/C/man3/sigpause.3:82
7263 "The classical BSD version of this function appeared in 4.2BSD. It sets the "
7264 "process's signal mask to I<sigmask>. UNIX 95 standardized the incompatible "
7265 "System V version of this function, which removes only the specified signal "
7266 "I<sig> from the process's signal mask. The unfortunate situation with two "
7267 "incompatible functions with the same name was solved by the "
7268 "B<\\%sigsuspend>(2) function, that takes a I<sigset_t\\ *> argument "
7269 "(instead of an I<int>)."
7273 #: build/C/man3/sigpause.3:85
7275 "On Linux, this routine is a system call only on the Sparc (sparc64) "
7280 #: build/C/man3/sigpause.3:87
7281 msgid "Libc4 and libc5 know only about the BSD version."
7285 #. For the BSD version, one usually uses a zero
7287 #. to indicate that no signals are to be blocked.
7289 #: build/C/man3/sigpause.3:111
7291 "Glibc uses the BSD version if the B<_BSD_SOURCE> feature test macro is "
7292 "defined and none of B<_POSIX_SOURCE>, B<_POSIX_C_SOURCE>, B<_XOPEN_SOURCE>, "
7293 "B<_GNU_SOURCE>, or B<_SVID_SOURCE> is defined. Otherwise, the System V "
7294 "version is used (and B<_XOPEN_SOURCE> must be defined to obtain the "
7295 "declaration). Since glibc 2.19, only the System V version is exposed by "
7296 "I<E<lt>signal.hE<gt>>; applications that formerly used the BSD B<sigpause>() "
7297 "should be amended to use B<sigsuspend>(2)."
7301 #: build/C/man3/sigpause.3:119
7303 "B<kill>(2), B<sigaction>(2), B<sigprocmask>(2), B<sigsuspend>(2), "
7304 "B<sigblock>(3), B<sigvec>(3), B<feature_test_macros>(7)"
7308 #: build/C/man2/sigpending.2:29
7314 #: build/C/man2/sigpending.2:29
7320 #: build/C/man2/sigpending.2:32
7321 msgid "sigpending - examine pending signals"
7325 #: build/C/man2/sigpending.2:36
7326 msgid "B<int sigpending(sigset_t *>I<set>B<);>"
7330 #: build/C/man2/sigpending.2:45
7332 "B<sigpending>(): _POSIX_C_SOURCE\\ E<gt>=\\ 1 || _XOPEN_SOURCE || "
7337 #: build/C/man2/sigpending.2:53
7339 "B<sigpending>() returns the set of signals that are pending for delivery to "
7340 "the calling thread (i.e., the signals which have been raised while "
7341 "blocked). The mask of pending signals is returned in I<set>."
7345 #: build/C/man2/sigpending.2:59
7347 "B<sigpending>() returns 0 on success and -1 on error. In the event of an "
7348 "error, I<errno> is set to indicate the cause."
7352 #: build/C/man2/sigpending.2:64
7354 "I<set> points to memory which is not a valid part of the process address "
7359 #: build/C/man2/sigpending.2:74
7361 "If a signal is both blocked and has a disposition of \"ignored\", it is "
7362 "I<not> added to the mask of pending signals when generated."
7366 #: build/C/man2/sigpending.2:79
7368 "The set of signals that is pending for a thread is the union of the set of "
7369 "signals that is pending for that thread and the set of signals that is "
7370 "pending for the process as a whole; see B<signal>(7)."
7374 #: build/C/man2/sigpending.2:91
7376 "In versions of glibc up to and including 2.2.1, there is a bug in the "
7377 "wrapper function for B<sigpending>() which means that information about "
7378 "pending real-time signals is not correctly returned."
7382 #: build/C/man2/sigpending.2:99
7384 "B<kill>(2), B<sigaction>(2), B<signal>(2), B<sigprocmask>(2), "
7385 "B<sigsuspend>(2), B<sigsetops>(3), B<signal>(7)"
7389 #: build/C/man2/sigprocmask.2:29
7395 #: build/C/man2/sigprocmask.2:32
7396 msgid "sigprocmask - examine and change blocked signals"
7400 #: build/C/man2/sigprocmask.2:37
7402 "B<int sigprocmask(int >I<how>B<, const sigset_t *>I<set>B<,> B<sigset_t "
7407 #: build/C/man2/sigprocmask.2:46
7409 "B<sigprocmask>(): _POSIX_C_SOURCE\\ E<gt>=\\ 1 || _XOPEN_SOURCE || "
7414 #: build/C/man2/sigprocmask.2:55
7416 "B<sigprocmask>() is used to fetch and/or change the signal mask of the "
7417 "calling thread. The signal mask is the set of signals whose delivery is "
7418 "currently blocked for the caller (see also B<signal>(7) for more details)."
7422 #: build/C/man2/sigprocmask.2:59
7423 msgid "The behavior of the call is dependent on the value of I<how>, as follows."
7427 #: build/C/man2/sigprocmask.2:59
7429 msgid "B<SIG_BLOCK>"
7433 #: build/C/man2/sigprocmask.2:64
7435 "The set of blocked signals is the union of the current set and the I<set> "
7440 #: build/C/man2/sigprocmask.2:64
7442 msgid "B<SIG_UNBLOCK>"
7446 #: build/C/man2/sigprocmask.2:70
7448 "The signals in I<set> are removed from the current set of blocked signals. "
7449 "It is permissible to attempt to unblock a signal which is not blocked."
7453 #: build/C/man2/sigprocmask.2:70
7455 msgid "B<SIG_SETMASK>"
7459 #: build/C/man2/sigprocmask.2:74
7460 msgid "The set of blocked signals is set to the argument I<set>."
7464 #: build/C/man2/sigprocmask.2:79
7466 "If I<oldset> is non-NULL, the previous value of the signal mask is stored in "
7471 #: build/C/man2/sigprocmask.2:88
7473 "If I<set> is NULL, then the signal mask is unchanged (i.e., I<how> is "
7474 "ignored), but the current value of the signal mask is nevertheless returned "
7475 "in I<oldset> (if it is not NULL)."
7479 #: build/C/man2/sigprocmask.2:93
7481 "The use of B<sigprocmask>() is unspecified in a multithreaded process; see "
7482 "B<pthread_sigmask>(3)."
7486 #: build/C/man2/sigprocmask.2:99
7488 "B<sigprocmask>() returns 0 on success and -1 on error. In the event of an "
7489 "error, I<errno> is set to indicate the cause."
7493 #: build/C/man2/sigprocmask.2:107
7495 "the I<set> or I<oldset> argument points outside the process's allocated "
7500 #: build/C/man2/sigprocmask.2:112
7501 msgid "The value specified in I<how> was invalid."
7505 #: build/C/man2/sigprocmask.2:118
7507 "It is not possible to block B<SIGKILL> or B<SIGSTOP>. Attempts to do so are "
7512 #: build/C/man2/sigprocmask.2:120
7513 msgid "Each of the threads in a process has its own signal mask."
7517 #: build/C/man2/sigprocmask.2:140
7519 "If B<SIGBUS>, B<SIGFPE>, B<SIGILL>, or B<SIGSEGV> are generated while they "
7520 "are blocked, the result is undefined, unless the signal was generated by "
7521 "B<kill>(2), B<sigqueue>(3), or B<raise>(3)."
7525 #: build/C/man2/sigprocmask.2:155
7527 "B<kill>(2), B<pause>(2), B<sigaction>(2), B<signal>(2), B<sigpending>(2), "
7528 "B<sigsuspend>(2), B<pthread_sigmask>(3), B<sigqueue>(3), B<sigsetops>(3), "
7533 #: build/C/man3/sigqueue.3:28
7539 #: build/C/man3/sigqueue.3:28 build/C/man3/sigwait.3:26
7545 #: build/C/man3/sigqueue.3:31
7546 msgid "sigqueue - queue a signal and data to a process"
7550 #: build/C/man3/sigqueue.3:35
7552 "B<int sigqueue(pid_t >I<pid>B<, int >I<sig>B<, const union sigval "
7557 #: build/C/man3/sigqueue.3:43
7558 msgid "B<sigqueue>(): _POSIX_C_SOURCE\\ E<gt>=\\ 199309L"
7562 #: build/C/man3/sigqueue.3:55
7564 "B<sigqueue>() sends the signal specified in I<sig> to the process whose PID "
7565 "is given in I<pid>. The permissions required to send a signal are the same "
7566 "as for B<kill>(2). As with B<kill>(2), the null signal (0) can be used to "
7567 "check if a process with a given PID exists."
7571 #: build/C/man3/sigqueue.3:60
7573 "The I<value> argument is used to specify an accompanying item of data "
7574 "(either an integer or a pointer value) to be sent with the signal, and has "
7575 "the following type:"
7579 #: build/C/man3/sigqueue.3:67
7584 " void *sival_ptr;\n"
7589 #: build/C/man3/sigqueue.3:83
7591 "If the receiving process has installed a handler for this signal using the "
7592 "B<SA_SIGINFO> flag to B<sigaction>(2), then it can obtain this data via the "
7593 "I<si_value> field of the I<siginfo_t> structure passed as the second "
7594 "argument to the handler. Furthermore, the I<si_code> field of that "
7595 "structure will be set to B<SI_QUEUE>."
7599 #: build/C/man3/sigqueue.3:91
7601 "On success, B<sigqueue>() returns 0, indicating that the signal was "
7602 "successfully queued to the receiving process. Otherwise, -1 is returned and "
7603 "I<errno> is set to indicate the error."
7607 #: build/C/man3/sigqueue.3:102
7608 msgid "I<sig> was invalid."
7612 #: build/C/man3/sigqueue.3:108
7614 "The process does not have permission to send the signal to the receiving "
7615 "process. For the required permissions, see B<kill>(2)."
7619 #: build/C/man3/sigqueue.3:112
7620 msgid "No process has a PID matching I<pid>."
7624 #: build/C/man3/sigqueue.3:114
7625 msgid "This system call first appeared in Linux 2.2."
7629 #: build/C/man3/sigqueue.3:119
7630 msgid "The B<sigqueue>() function is thread-safe."
7634 #: build/C/man3/sigqueue.3:129
7636 "If this function results in the sending of a signal to the process that "
7637 "invoked it, and that signal was not blocked by the calling thread, and no "
7638 "other threads were willing to handle this signal (either by having it "
7639 "unblocked, or by waiting for it using B<sigwait>(3)), then at least some "
7640 "signal must be delivered to this thread before this function returns."
7644 #: build/C/man3/sigqueue.3:144
7646 "On Linux, this function is implemented using the B<rt_sigqueueinfo>(2) "
7647 "system call. The system call differs in its third argument, which is the "
7648 "I<siginfo_t> structure that will be supplied to the receiving process's "
7649 "signal handler or returned by the receiving process's B<sigtimedwait>(2) "
7650 "call. Inside the glibc B<sigqueue>() wrapper, this argument, I<uinfo>, is "
7651 "initialized as follows:"
7655 #: build/C/man3/sigqueue.3:152
7658 "uinfo.si_signo = sig; /* Argument supplied to sigqueue() */\n"
7659 "uinfo.si_code = SI_QUEUE;\n"
7660 "uinfo.si_pid = getpid(); /* Process ID of sender */\n"
7661 "uinfo.si_uid = getuid(); /* Real UID of sender */\n"
7662 "uinfo.si_value = val; /* Argument supplied to sigqueue() */\n"
7666 #: build/C/man3/sigqueue.3:162
7668 "B<kill>(2), B<rt_sigqueueinfo>(2), B<sigaction>(2), B<signal>(2), "
7669 "B<pthread_sigqueue>(3), B<sigwait>(3), B<signal>(7)"
7673 #: build/C/man2/sigreturn.2:29
7679 #: build/C/man2/sigreturn.2:32
7680 msgid "sigreturn - return from signal handler and cleanup stack frame"
7684 #: build/C/man2/sigreturn.2:34
7685 msgid "B<int sigreturn(unsigned long >I<__unused>B<);>"
7689 #: build/C/man2/sigreturn.2:42
7691 "When the Linux kernel creates the stack frame for a signal handler, a call "
7692 "to B<sigreturn>() is inserted into the stack frame so that upon return from "
7693 "the signal handler, B<sigreturn>() will be called."
7697 #: build/C/man2/sigreturn.2:53
7699 "This B<sigreturn>() call undoes everything that was done\\(emchanging the "
7700 "process's signal mask, switching stacks (see B<sigaltstack>(2))\\(emin order "
7701 "to invoke the signal handler: it restores the process's signal mask, "
7702 "switches stacks, and restores the process's context (registers, processor "
7703 "flags), so that the process directly resumes execution at the point where it "
7704 "was interrupted by the signal."
7708 #: build/C/man2/sigreturn.2:56
7709 msgid "B<sigreturn>() never returns."
7713 #: build/C/man2/sigreturn.2:56
7719 #: build/C/man2/sigreturn.2:58
7720 msgid "/usr/src/linux/arch/i386/kernel/signal.c"
7724 #: build/C/man2/sigreturn.2:60
7725 msgid "/usr/src/linux/arch/alpha/kernel/entry.S"
7729 #: build/C/man2/sigreturn.2:64
7731 "B<sigreturn>() is specific to Linux and should not be used in programs "
7732 "intended to be portable."
7736 #: build/C/man2/sigreturn.2:74
7738 "The B<sigreturn>() call is used by the kernel to implement signal "
7739 "handlers. It should B<never> be called directly. Better yet, the specific "
7740 "use of the I<__unused> argument varies depending on the architecture."
7744 #: build/C/man2/sigreturn.2:80
7746 "B<kill>(2), B<restart_syscall>(2), B<sigaltstack>(2), B<signal>(2), "
7751 #: build/C/man3/sigset.3:26
7757 #: build/C/man3/sigset.3:29
7758 msgid "sigset, sighold, sigrelse, sigignore - System V signal API"
7762 #: build/C/man3/sigset.3:35
7763 msgid "B<sighandler_t sigset(int >I<sig>B<, sighandler_t >I<disp>B<);>"
7767 #: build/C/man3/sigset.3:37
7768 msgid "B<int sighold(int >I<sig>B<);>"
7772 #: build/C/man3/sigset.3:39
7773 msgid "B<int sigrelse(int >I<sig>B<);>"
7777 #: build/C/man3/sigset.3:41
7778 msgid "B<int sigignore(int >I<sig>B<);>"
7782 #: build/C/man3/sigset.3:52
7783 msgid "B<sigset>(), B<sighold>(), B<sigrelse>(), B<sigignore>():"
7787 #: build/C/man3/sigset.3:56
7788 msgid "_XOPEN_SOURCE\\ E<gt>=\\ 500 || _XOPEN_SOURCE\\ &&\\ _XOPEN_SOURCE_EXTENDED"
7792 #: build/C/man3/sigset.3:65
7794 "These functions are provided in glibc as a compatibility interface for "
7795 "programs that make use of the historical System V signal API. This API is "
7796 "obsolete: new applications should use the POSIX signal API (B<sigaction>(2), "
7797 "B<sigprocmask>(2), etc.)"
7801 #: build/C/man3/sigset.3:74
7803 "The B<sigset>() function modifies the disposition of the signal I<sig>. "
7804 "The I<disp> argument can be the address of a signal handler function, or one "
7805 "of the following constants:"
7809 #: build/C/man3/sigset.3:74
7815 #: build/C/man3/sigset.3:79
7816 msgid "Reset the disposition of I<sig> to the default."
7820 #: build/C/man3/sigset.3:79
7826 #: build/C/man3/sigset.3:83
7827 msgid "Ignore I<sig>."
7831 #: build/C/man3/sigset.3:83
7837 #: build/C/man3/sigset.3:90
7839 "Add I<sig> to the process's signal mask, but leave the disposition of I<sig> "
7844 #: build/C/man3/sigset.3:96
7846 "If I<disp> specifies the address of a signal handler, then I<sig> is added "
7847 "to the process's signal mask during execution of the handler."
7851 #: build/C/man3/sigset.3:104
7853 "If I<disp> was specified as a value other than B<SIG_HOLD>, then I<sig> is "
7854 "removed from the process's signal mask."
7858 #: build/C/man3/sigset.3:110 build/C/man3/sigvec.3:87
7859 msgid "The dispositions for B<SIGKILL> and B<SIGSTOP> cannot be changed."
7863 #: build/C/man3/sigset.3:116
7864 msgid "The B<sighold>() function adds I<sig> to the calling process's signal mask."
7868 #: build/C/man3/sigset.3:122
7870 "The B<sigrelse>() function removes I<sig> from the calling process's signal "
7875 #: build/C/man3/sigset.3:129
7876 msgid "The B<sigignore>() function sets the disposition of I<sig> to B<SIG_IGN>."
7880 #: build/C/man3/sigset.3:145
7882 "On success, B<sigset>() returns B<SIG_HOLD> if I<sig> was blocked before "
7883 "the call, or the signal's previous disposition if it was not blocked before "
7884 "the call. On error, B<sigset>() returns -1, with I<errno> set to indicate "
7885 "the error. (But see BUGS below.)"
7889 #: build/C/man3/sigset.3:154
7891 "The B<sighold>(), B<sigrelse>(), and B<sigignore>() functions return 0 on "
7892 "success; on error, these functions return -1 and set I<errno> to indicate "
7897 #: build/C/man3/sigset.3:161
7899 "For B<sigset>() see the ERRORS under B<sigaction>(2) and "
7900 "B<sigprocmask>(2)."
7904 #: build/C/man3/sigset.3:168
7905 msgid "For B<sighold>() and B<sigrelse>() see the ERRORS under B<sigprocmask>(2)."
7909 #: build/C/man3/sigset.3:173
7910 msgid "For B<sigignore>(), see the errors under B<sigaction>(2)."
7914 #: build/C/man3/sigset.3:190
7916 "SVr4, POSIX.1-2001. These functions are obsolete: do not use them in new "
7917 "programs. POSIX.1-2008 marks B<sighold>(), B<sigignore>(), B<sigpause>(), "
7918 "B<sigrelse>(), and B<sigset>() as obsolete, recommending the use of "
7919 "B<sigaction>(2), B<sigprocmask>(2), B<pthread_sigmask>(3), and "
7920 "B<sigsuspend>(2) instead."
7924 #: build/C/man3/sigset.3:192
7925 msgid "These functions appeared in glibc version 2.1."
7929 #: build/C/man3/sigset.3:198
7931 "The I<sighandler_t> type is a GNU extension; it is used on this page only to "
7932 "make the B<sigset>() prototype more easily readable."
7936 #: build/C/man3/sigset.3:206
7938 "The B<sigset>() function provides reliable signal handling semantics (as "
7939 "when calling B<sigaction>(2) with I<sa_mask> equal to 0)."
7943 #: build/C/man3/sigset.3:224
7945 "On System V, the B<signal>() function provides unreliable semantics (as "
7946 "when calling B<sigaction>(2) with I<sa_mask> equal to I<SA_RESETHAND | "
7947 "SA_NODEFER>). On BSD, B<signal>() provides reliable semantics. "
7948 "POSIX.1-2001 leaves these aspects of B<signal>() unspecified. See "
7949 "B<signal>(2) for further details."
7953 #: build/C/man3/sigset.3:232 build/C/man3/sigvec.3:265
7955 "In order to wait for a signal, BSD and System V both provided a function "
7956 "named B<sigpause>(3), but this function has a different argument on the two "
7957 "systems. See B<sigpause>(3) for details."
7961 #: build/C/man3/sigset.3:241
7963 "In versions of glibc before 2.2, B<sigset>() did not unblock I<sig> if "
7964 "I<disp> was specified as a value other than B<SIG_HOLD>."
7967 #. See http://sourceware.org/bugzilla/show_bug.cgi?id=1951
7969 #: build/C/man3/sigset.3:266
7971 "In versions of glibc before 2.5, B<sigset>() does not correctly return the "
7972 "previous disposition of the signal in two cases. First, if I<disp> is "
7973 "specified as B<SIG_HOLD>, then a successful B<sigset>() always returns "
7974 "B<SIG_HOLD>. Instead, it should return the previous disposition of the "
7975 "signal (unless the signal was blocked, in which case B<SIG_HOLD> should be "
7976 "returned). Second, if the signal is currently blocked, then the return "
7977 "value of a successful B<sigset>() should be B<SIG_HOLD>. Instead, the "
7978 "previous disposition of the signal is returned. These problems have been "
7979 "fixed since glibc 2.5."
7983 #: build/C/man3/sigset.3:276
7985 "B<kill>(2), B<pause>(2), B<sigaction>(2), B<signal>(2), B<sigprocmask>(2), "
7986 "B<raise>(3), B<sigpause>(3), B<sigvec>(3), B<signal>(7)"
7990 #: build/C/man3/sigsetops.3:31
7996 #: build/C/man3/sigsetops.3:35
7998 "sigemptyset, sigfillset, sigaddset, sigdelset, sigismember - POSIX signal "
8003 #: build/C/man3/sigsetops.3:39
8004 msgid "B<int sigemptyset(sigset_t *>I<set>B<);>"
8008 #: build/C/man3/sigsetops.3:41
8009 msgid "B<int sigfillset(sigset_t *>I<set>B<);>"
8013 #: build/C/man3/sigsetops.3:43
8014 msgid "B<int sigaddset(sigset_t *>I<set>B<, int >I<signum>B<);>"
8018 #: build/C/man3/sigsetops.3:45
8019 msgid "B<int sigdelset(sigset_t *>I<set>B<, int >I<signum>B<);>"
8023 #: build/C/man3/sigsetops.3:47
8024 msgid "B<int sigismember(const sigset_t *>I<set>B<, int >I<signum>B<);>"
8028 #: build/C/man3/sigsetops.3:59
8030 "B<sigemptyset>(), B<sigfillset>(), B<sigaddset>(), B<sigdelset>(), "
8035 #: build/C/man3/sigsetops.3:61
8036 msgid "_POSIX_C_SOURCE\\ E<gt>=\\ 1 || _XOPEN_SOURCE || _POSIX_SOURCE"
8040 #: build/C/man3/sigsetops.3:65
8041 msgid "These functions allow the manipulation of POSIX signal sets."
8045 #: build/C/man3/sigsetops.3:70
8047 "B<sigemptyset>() initializes the signal set given by I<set> to empty, with "
8048 "all signals excluded from the set."
8052 #: build/C/man3/sigsetops.3:75
8053 msgid "B<sigfillset>() initializes I<set> to full, including all signals."
8057 #: build/C/man3/sigsetops.3:83
8059 "B<sigaddset>() and B<sigdelset>() add and delete respectively signal "
8060 "I<signum> from I<set>."
8064 #: build/C/man3/sigsetops.3:89
8065 msgid "B<sigismember>() tests whether I<signum> is a member of I<set>."
8069 #: build/C/man3/sigsetops.3:107
8071 "Objects of type I<sigset_t> must be initialized by a call to either "
8072 "B<sigemptyset>() or B<sigfillset>() before being passed to the functions "
8073 "B<sigaddset>(), B<sigdelset>() and B<sigismember>() or the additional "
8074 "glibc functions described below (B<sigisemptyset>(), B<sigandset>(), and "
8075 "B<sigorset>()). The results are undefined if this is not done."
8079 #: build/C/man3/sigsetops.3:114
8081 "B<sigemptyset>(), B<sigfillset>(), B<sigaddset>(), and B<sigdelset>() "
8082 "return 0 on success and -1 on error."
8086 #: build/C/man3/sigsetops.3:126
8088 "B<sigismember>() returns 1 if I<signum> is a member of I<set>, 0 if "
8089 "I<signum> is not a member, and -1 on error. On error, these functions set "
8090 "I<errno> to indicate the cause."
8094 #: build/C/man3/sigsetops.3:131
8095 msgid "I<sig> is not a valid signal."
8099 #: build/C/man3/sigsetops.3:144
8101 "The B<sigemptyset>(), B<sigfillset>(), B<sigaddset>(), B<sigdelset>(), "
8102 "B<sigismember>(), B<sigisemptyset>(), B<sigorset>(), and B<sigandset>() "
8103 "functions are thread-safe."
8107 #: build/C/man3/sigsetops.3:147
8113 #: build/C/man3/sigsetops.3:153
8115 "If the B<_GNU_SOURCE> feature test macro is defined, then "
8116 "I<E<lt>signal.hE<gt>> exposes three other functions for manipulating signal "
8121 #: build/C/man3/sigsetops.3:160
8124 "B<int sigisemptyset(const sigset_t *>I<set>B<);>\n"
8125 "B<int sigorset(sigset_t *>I<dest>B<, const sigset_t *>I<left>B<,>\n"
8126 "B< const sigset_t *>I<right>B<);>\n"
8127 "B<int sigandset(sigset_t *>I<dest>B<, const sigset_t *>I<left>B<,>\n"
8128 "B< const sigset_t *>I<right>B<);>\n"
8132 #: build/C/man3/sigsetops.3:166
8134 "B<sigisemptyset>() returns 1 if I<set> contains no signals, and 0 "
8139 #: build/C/man3/sigsetops.3:182
8141 "B<sigorset>() places the union of the sets I<left> and I<right> in "
8142 "I<dest>. B<sigandset>() places the intersection of the sets I<left> and "
8143 "I<right> in I<dest>. Both functions return 0 on success, and -1 on failure."
8147 #: build/C/man3/sigsetops.3:185
8149 "These functions are nonstandard (a few other systems provide similar "
8150 "functions) and their use should be avoided in portable applications."
8154 #: build/C/man3/sigsetops.3:190
8155 msgid "B<sigaction>(2), B<sigpending>(2), B<sigprocmask>(2), B<sigsuspend>(2)"
8159 #: build/C/man2/sigsuspend.2:29
8165 #: build/C/man2/sigsuspend.2:32
8166 msgid "sigsuspend - wait for a signal"
8170 #: build/C/man2/sigsuspend.2:36
8171 msgid "B<int sigsuspend(const sigset_t *>I<mask>B<);>"
8175 #: build/C/man2/sigsuspend.2:45
8177 "B<sigsuspend>(): _POSIX_C_SOURCE\\ E<gt>=\\ 1 || _XOPEN_SOURCE || "
8182 #: build/C/man2/sigsuspend.2:53
8184 "B<sigsuspend>() temporarily replaces the signal mask of the calling process "
8185 "with the mask given by I<mask> and then suspends the process until delivery "
8186 "of a signal whose action is to invoke a signal handler or to terminate a "
8191 #: build/C/man2/sigsuspend.2:62
8193 "If the signal terminates the process, then B<sigsuspend>() does not "
8194 "return. If the signal is caught, then B<sigsuspend>() returns after the "
8195 "signal handler returns, and the signal mask is restored to the state before "
8196 "the call to B<sigsuspend>()."
8200 #: build/C/man2/sigsuspend.2:70
8202 "It is not possible to block B<SIGKILL> or B<SIGSTOP>; specifying these "
8203 "signals in I<mask>, has no effect on the process's signal mask."
8207 #: build/C/man2/sigsuspend.2:76
8209 "B<sigsuspend>() always returns -1, with I<errno> set to indicate the error "
8210 "(normally, B<EINTR>)."
8214 #: build/C/man2/sigsuspend.2:81
8216 "I<mask> points to memory which is not a valid part of the process address "
8221 #: build/C/man2/sigsuspend.2:84
8222 msgid "The call was interrupted by a signal."
8226 #: build/C/man2/sigsuspend.2:104
8228 "Normally, B<sigsuspend>() is used in conjunction with B<sigprocmask>(2) in "
8229 "order to prevent delivery of a signal during the execution of a critical "
8230 "code section. The caller first blocks the signals with B<sigprocmask>(2). "
8231 "When the critical code has completed, the caller then waits for the signals "
8232 "by calling B<sigsuspend>() with the signal mask that was returned by "
8233 "B<sigprocmask>(2) (in the I<oldset> argument)."
8237 #: build/C/man2/sigsuspend.2:118
8239 "B<kill>(2), B<pause>(2), B<sigaction>(2), B<signal>(2), B<sigprocmask>(2), "
8240 "B<sigwaitinfo>(2), B<sigsetops>(3), B<sigwait>(3), B<signal>(7)"
8244 #: build/C/man3/sigvec.3:26
8250 #: build/C/man3/sigvec.3:26
8256 #: build/C/man3/sigvec.3:29
8257 msgid "sigvec, sigblock, sigsetmask, siggetmask, sigmask - BSD signal API"
8261 #: build/C/man3/sigvec.3:33
8263 "B<int sigvec(int >I<sig>B<, const struct sigvec *>I<vec>B<, struct sigvec "
8268 #: build/C/man3/sigvec.3:35
8269 msgid "B<int sigmask(int >I<signum>B<);>"
8273 #: build/C/man3/sigvec.3:37
8274 msgid "B<int sigblock(int >I<mask>B<);>"
8278 #: build/C/man3/sigvec.3:39
8279 msgid "B<int sigsetmask(int >I<mask>B<);>"
8283 #: build/C/man3/sigvec.3:41
8284 msgid "B<int siggetmask(void);>"
8288 #: build/C/man3/sigvec.3:49
8289 msgid "All functions shown above: _BSD_SOURCE"
8293 #: build/C/man3/sigvec.3:56
8295 "These functions are provided in glibc as a compatibility interface for "
8296 "programs that make use of the historical BSD signal API. This API is "
8297 "obsolete: new applications should use the POSIX signal API (B<sigaction>(2), "
8298 "B<sigprocmask>(2), etc.)."
8302 #: build/C/man3/sigvec.3:81
8304 "The B<sigvec>() function sets and/or gets the disposition of the signal "
8305 "I<sig> (like the POSIX B<sigaction>(2)). If I<vec> is not NULL, it points "
8306 "to a I<sigvec> structure that defines the new disposition for I<sig>. If "
8307 "I<ovec> is not NULL, it points to a I<sigvec> structure that is used to "
8308 "return the previous disposition of I<sig>. To obtain the current "
8309 "disposition of I<sig> without changing it, specify NULL for I<vec>, and a "
8310 "non-null pointer for I<ovec>."
8314 #: build/C/man3/sigvec.3:91
8315 msgid "The I<sigvec> structure has the following form:"
8319 #: build/C/man3/sigvec.3:99
8323 " void (*sv_handler)(int); /* Signal disposition */\n"
8324 " int sv_mask; /* Signals to be blocked in handler */\n"
8325 " int sv_flags; /* Flags */\n"
8330 #: build/C/man3/sigvec.3:110
8332 "The I<sv_handler> field specifies the disposition of the signal, and is "
8333 "either: the address of a signal handler function; B<SIG_DFL>, meaning the "
8334 "default disposition applies for the signal; or B<SIG_IGN>, meaning that the "
8335 "signal is ignored."
8339 #: build/C/man3/sigvec.3:124
8341 "If I<sv_handler> specifies the address of a signal handler, then I<sv_mask> "
8342 "specifies a mask of signals that are to be blocked while the handler is "
8343 "executing. In addition, the signal for which the handler is invoked is also "
8344 "blocked. Attempts to block B<SIGKILL> or B<SIGSTOP> are silently ignored."
8348 #: build/C/man3/sigvec.3:131
8350 "If I<sv_handler> specifies the address of a signal handler, then the "
8351 "I<sv_flags> field specifies flags controlling what happens when the handler "
8352 "is called. This field may contain zero or more of the following flags:"
8356 #: build/C/man3/sigvec.3:131
8358 msgid "B<SV_INTERRUPT>"
8362 #: build/C/man3/sigvec.3:139
8364 "If the signal handler interrupts a blocking system call, then upon return "
8365 "from the handler the system call will not be restarted: instead it will fail "
8366 "with the error B<EINTR>. If this flag is not specified, then system calls "
8367 "are restarted by default."
8371 #: build/C/man3/sigvec.3:139
8373 msgid "B<SV_RESETHAND>"
8377 #: build/C/man3/sigvec.3:148
8379 "Reset the disposition of the signal to the default before calling the signal "
8380 "handler. If this flag is not specified, then the handler remains "
8381 "established until explicitly removed by a later call to B<sigvec>() or "
8382 "until the process performs an B<execve>(2)."
8386 #: build/C/man3/sigvec.3:148
8388 msgid "B<SV_ONSTACK>"
8392 #: build/C/man3/sigvec.3:155
8394 "Handle the signal on the alternate signal stack (historically established "
8395 "under BSD using the obsolete B<sigstack>() function; the POSIX replacement "
8396 "is B<sigaltstack>(2))."
8400 #: build/C/man3/sigvec.3:165
8402 "The B<sigmask>() macro constructs and returns a \"signal mask\" for "
8403 "I<signum>. For example, we can initialize the I<vec.sv_mask> field given to "
8404 "B<sigvec>() using code such as the following:"
8408 #: build/C/man3/sigvec.3:170
8411 " vec.sv_mask = sigmask(SIGQUIT) | sigmask(SIGABRT);\n"
8412 " /* Block SIGQUIT and SIGABRT during\n"
8413 " handler execution */\n"
8417 #: build/C/man3/sigvec.3:185
8419 "The B<sigblock>() function adds the signals in I<mask> to the process's "
8420 "signal mask (like POSIX I<sigprocmask(SIG_BLOCK)>), and returns the "
8421 "process's previous signal mask. Attempts to block B<SIGKILL> or B<SIGSTOP> "
8422 "are silently ignored."
8426 #: build/C/man3/sigvec.3:193
8428 "The B<sigsetmask>() function sets the process's signal mask to the value "
8429 "given in I<mask> (like POSIX I<sigprocmask(SIG_SETMASK)>), and returns the "
8430 "process's previous signal mask."
8434 #: build/C/man3/sigvec.3:199
8436 "The B<siggetmask>() function returns the process's current signal mask. "
8437 "This call is equivalent to I<sigblock(0)>."
8441 #: build/C/man3/sigvec.3:205
8443 "The B<sigvec>() function returns 0 on success; on error, it returns -1 and "
8444 "sets I<errno> to indicate the error."
8448 #: build/C/man3/sigvec.3:211
8450 "The B<sigblock>() and B<sigsetmask>() functions return the previous signal "
8455 #: build/C/man3/sigvec.3:216
8456 msgid "The B<sigmask>() macro returns the signal mask for I<signum>."
8460 #: build/C/man3/sigvec.3:221
8461 msgid "See the ERRORS under B<sigaction>(2) and B<sigprocmask>(2)."
8465 #: build/C/man3/sigvec.3:230
8467 "The B<sigvec>(), B<sigblock>(), B<sigsetmask>(), and B<siggetmask>() "
8468 "functions are thread-safe."
8472 #: build/C/man3/sigvec.3:234
8473 msgid "The B<sigmask>() macro is thread-safe."
8477 #: build/C/man3/sigvec.3:240
8479 "All of these functions were in 4.3BSD, except B<siggetmask>(), whose origin "
8480 "is unclear. These functions are obsolete: do not use them in new programs."
8484 #: build/C/man3/sigvec.3:257
8486 "On 4.3BSD, the B<signal>() function provided reliable semantics (as when "
8487 "calling B<sigvec>() with I<vec.sv_mask> equal to 0). On System V, "
8488 "B<signal>() provides unreliable semantics. POSIX.1-2001 leaves these "
8489 "aspects of B<signal>() unspecified. See B<signal>(2) for further details."
8493 #: build/C/man3/sigvec.3:275
8495 "B<kill>(2), B<pause>(2), B<sigaction>(2), B<signal>(2), B<sigprocmask>(2), "
8496 "B<raise>(3), B<sigpause>(3), B<sigset>(3), B<signal>(7)"
8500 #: build/C/man3/sigwait.3:26
8506 #: build/C/man3/sigwait.3:29
8507 msgid "sigwait - wait for a signal"
8511 #: build/C/man3/sigwait.3:34
8513 msgid "B< int sigwait(const sigset_t *>I<set>B<, int *>I<sig>B<);>\n"
8517 #: build/C/man3/sigwait.3:44
8518 msgid "B<sigwait>(): _POSIX_C_SOURCE\\ E<gt>=\\ 1 || _XOPEN_SOURCE || _POSIX_SOURCE"
8522 #: build/C/man3/sigwait.3:56
8524 "The B<sigwait>() function suspends execution of the calling thread until "
8525 "one of the signals specified in the signal set I<set> becomes pending. The "
8526 "function accepts the signal (removes it from the pending list of signals), "
8527 "and returns the signal number in I<sig>."
8531 #: build/C/man3/sigwait.3:62
8533 "The operation of B<sigwait>() is the same as B<sigwaitinfo>(2), except "
8538 #: build/C/man3/sigwait.3:67
8540 "B<sigwait>() returns only the signal number, rather than a I<siginfo_t> "
8541 "structure describing the signal."
8545 #: build/C/man3/sigwait.3:69
8546 msgid "The return values of the two functions are different."
8550 #: build/C/man3/sigwait.3:74
8552 "On success, B<sigwait>() returns 0. On error, it returns a positive error "
8553 "number (listed in ERRORS)."
8556 #. Does not occur for glibc.
8558 #: build/C/man3/sigwait.3:80
8559 msgid "I<set> contains an invalid signal number."
8563 #: build/C/man3/sigwait.3:85
8564 msgid "The B<sigwait>() function is thread-safe."
8568 #: build/C/man3/sigwait.3:91
8569 msgid "B<sigwait>() is implemented using B<sigtimedwait>(2)."
8573 #: build/C/man3/sigwait.3:94
8574 msgid "See B<pthread_sigmask>(3)."
8578 #: build/C/man3/sigwait.3:102
8580 "B<sigaction>(2), B<signalfd>(2), B<sigpending>(2), B<sigsuspend>(2), "
8581 "B<sigwaitinfo>(2), B<sigsetops>(3), B<signal>(7)"
8585 #: build/C/man2/sigwaitinfo.2:25
8591 #: build/C/man2/sigwaitinfo.2:25 build/C/man2/wait.2:49
8597 #: build/C/man2/sigwaitinfo.2:28
8598 msgid "sigwaitinfo, sigtimedwait - synchronously wait for queued signals"
8602 #: build/C/man2/sigwaitinfo.2:33
8604 msgid "B<int sigwaitinfo(const sigset_t *>I<set>B<, siginfo_t *>I<info>B<);>\n"
8608 #: build/C/man2/sigwaitinfo.2:36
8611 "B<int sigtimedwait(const sigset_t *>I<set>B<, siginfo_t *>I<info>B<, >\n"
8612 "B< const struct timespec *>I<timeout>B<);>\n"
8616 #: build/C/man2/sigwaitinfo.2:46
8617 msgid "B<sigwaitinfo>(), B<sigtimedwait>(): _POSIX_C_SOURCE\\ E<gt>=\\ 199309L"
8621 #: build/C/man2/sigwaitinfo.2:56
8623 "B<sigwaitinfo>() suspends execution of the calling thread until one of the "
8624 "signals in I<set> is pending (If one of the signals in I<set> is already "
8625 "pending for the calling thread, B<sigwaitinfo>() will return immediately.)"
8629 #: build/C/man2/sigwaitinfo.2:68
8631 "B<sigwaitinfo>() removes the signal from the set of pending signals and "
8632 "returns the signal number as its function result. If the I<info> argument "
8633 "is not NULL, then the buffer that it points to is used to return a structure "
8634 "of type I<siginfo_t> (see B<sigaction>(2)) containing information about the "
8639 #: build/C/man2/sigwaitinfo.2:76
8641 "If multiple signals in I<set> are pending for the caller, the signal that is "
8642 "retrieved by B<sigwaitinfo>() is determined according to the usual ordering "
8643 "rules; see B<signal>(7) for further details."
8647 #: build/C/man2/sigwaitinfo.2:88
8649 "B<sigtimedwait>() operates in exactly the same way as B<sigwaitinfo>() "
8650 "except that it has an additional argument, I<timeout>, which specifies the "
8651 "interval for which the thread is suspended waiting for a signal. (This "
8652 "interval will be rounded up to the system clock granularity, and kernel "
8653 "scheduling delays mean that the interval may overrun by a small amount.) "
8654 "This argument is of the following type:"
8658 #: build/C/man2/sigwaitinfo.2:95
8661 "struct timespec {\n"
8662 " long tv_sec; /* seconds */\n"
8663 " long tv_nsec; /* nanoseconds */\n"
8668 #: build/C/man2/sigwaitinfo.2:105
8670 "If both fields of this structure are specified as 0, a poll is performed: "
8671 "B<sigtimedwait>() returns immediately, either with information about a "
8672 "signal that was pending for the caller, or with an error if none of the "
8673 "signals in I<set> was pending."
8677 #: build/C/man2/sigwaitinfo.2:114
8679 "On success, both B<sigwaitinfo>() and B<sigtimedwait>() return a signal "
8680 "number (i.e., a value greater than zero). On failure both calls return -1, "
8681 "with I<errno> set to indicate the error."
8685 #: build/C/man2/sigwaitinfo.2:123
8687 "No signal in I<set> was became pending within the I<timeout> period "
8688 "specified to B<sigtimedwait>()."
8692 #: build/C/man2/sigwaitinfo.2:129
8694 "The wait was interrupted by a signal handler; see B<signal>(7). (This "
8695 "handler was for a signal other than one of those in I<set>.)"
8699 #: build/C/man2/sigwaitinfo.2:133
8700 msgid "I<timeout> was invalid."
8704 #: build/C/man2/sigwaitinfo.2:153
8706 "In normal usage, the calling program blocks the signals in I<set> via a "
8707 "prior call to B<sigprocmask>(2) (so that the default disposition for these "
8708 "signals does not occur if they become pending between successive calls to "
8709 "B<sigwaitinfo>() or B<sigtimedwait>()) and does not establish handlers for "
8710 "these signals. In a multithreaded program, the signal should be blocked in "
8711 "all threads, in order to prevent the signal being treated according to its "
8712 "default disposition in a thread other than the one calling B<sigwaitinfo>() "
8713 "or B<sigtimedwait>())."
8717 #: build/C/man2/sigwaitinfo.2:158
8719 "The set of signals that is pending for a given thread is the union of the "
8720 "set of signals that is pending specifically for that thread and the set of "
8721 "signals that is pending for the process as a whole (see B<signal>(7))."
8725 #: build/C/man2/sigwaitinfo.2:164
8726 msgid "Attempts to wait for B<SIGKILL> and B<SIGSTOP> are silently ignored."
8730 #: build/C/man2/sigwaitinfo.2:173
8732 "If multiple threads of a process are blocked waiting for the same signal(s) "
8733 "in B<sigwaitinfo>() or B<sigtimedwait>(), then exactly one of the threads "
8734 "will actually receive the signal if it becomes pending for the process as a "
8735 "whole; which of the threads receives the signal is indeterminate."
8739 #: build/C/man2/sigwaitinfo.2:182
8741 "POSIX leaves the meaning of a NULL value for the I<timeout> argument of "
8742 "B<sigtimedwait>() unspecified, permitting the possibility that this has the "
8743 "same meaning as a call to B<sigwaitinfo>(), and indeed this is what is done "
8748 #: build/C/man2/sigwaitinfo.2:187
8750 "On Linux, B<sigwaitinfo>() is a library function implemented on top of "
8751 "B<sigtimedwait>()."
8755 #: build/C/man2/sigwaitinfo.2:199
8757 "B<kill>(2), B<sigaction>(2), B<signal>(2), B<signalfd>(2), B<sigpending>(2), "
8758 "B<sigprocmask>(2), B<sigqueue>(3), B<sigsetops>(3), B<sigwait>(3), "
8759 "B<signal>(7), B<time>(7)"
8763 #: build/C/man3/sysv_signal.3:25
8769 #: build/C/man3/sysv_signal.3:25
8775 #: build/C/man3/sysv_signal.3:28
8776 msgid "sysv_signal - signal handling with System V semantics"
8780 #: build/C/man3/sysv_signal.3:30
8781 msgid "B<#define _GNU_SOURCE> /* See feature_test_macros(7) */"
8785 #: build/C/man3/sysv_signal.3:36
8786 msgid "B<sighandler_t sysv_signal(int >I<signum>B<, sighandler_t >I<handler>B<);>"
8790 #: build/C/man3/sysv_signal.3:41
8792 "The B<sysv_signal>() function takes the same arguments, and performs the "
8793 "same task, as B<signal>(2)."
8797 #: build/C/man3/sysv_signal.3:51
8799 "However B<sysv_signal>() provides the System V unreliable signal semantics, "
8800 "that is: a) the disposition of the signal is reset to the default when the "
8801 "handler is invoked; b) delivery of further instances of the signal is not "
8802 "blocked while the signal handler is executing; and c) if the handler "
8803 "interrupts (certain) blocking system calls, then the system call is not "
8804 "automatically restarted."
8808 #: build/C/man3/sysv_signal.3:57
8810 "The B<sysv_signal>() function returns the previous value of the signal "
8811 "handler, or B<SIG_ERR> on error."
8815 #: build/C/man3/sysv_signal.3:65
8816 msgid "The B<sysv_signal>() function is thread-safe."
8820 #: build/C/man3/sysv_signal.3:67
8821 msgid "This function is nonstandard."
8825 #: build/C/man3/sysv_signal.3:73
8826 msgid "Use of B<sysv_signal>() should be avoided; use B<sigaction>(2) instead."
8830 #: build/C/man3/sysv_signal.3:84
8832 "On older Linux systems, B<sysv_signal>() and B<signal>(2) were "
8833 "equivalent. But on newer systems, B<signal>(2) provides reliable signal "
8834 "semantics; see B<signal>(2) for details."
8838 #: build/C/man3/sysv_signal.3:97
8839 msgid "B<sigaction>(2), B<signal>(2), B<bsd_signal>(3), B<signal>(7)"
8843 #: build/C/man2/timer_create.2:31
8845 msgid "TIMER_CREATE"
8849 #: build/C/man2/timer_create.2:31
8855 #: build/C/man2/timer_create.2:34
8856 msgid "timer_create - create a POSIX per-process timer"
8860 #: build/C/man2/timer_create.2:38
8863 "B<#include E<lt>signal.hE<gt>>\n"
8864 "B<#include E<lt>time.hE<gt>>\n"
8868 #: build/C/man2/timer_create.2:41
8871 "B<int timer_create(clockid_t >I<clockid>B<, struct sigevent *>I<sevp>B<,>\n"
8872 "B< timer_t *>I<timerid>B<);>\n"
8876 #: build/C/man2/timer_create.2:44 build/C/man2/timer_delete.2:37 build/C/man2/timer_getoverrun.2:37 build/C/man2/timer_settime.2:41
8877 msgid "Link with I<-lrt>."
8881 #: build/C/man2/timer_create.2:52
8882 msgid "B<timer_create>(): _POSIX_C_SOURCE\\ E<gt>=\\ 199309L"
8886 #: build/C/man2/timer_create.2:60
8888 "B<timer_create>() creates a new per-process interval timer. The ID of the "
8889 "new timer is returned in the buffer pointed to by I<timerid>, which must be "
8890 "a non-null pointer. This ID is unique within the process, until the timer "
8891 "is deleted. The new timer is initially disarmed."
8895 #: build/C/man2/timer_create.2:65
8897 "The I<clockid> argument specifies the clock that the new timer uses to "
8898 "measure time. It can be specified as one of the following values:"
8902 #: build/C/man2/timer_create.2:65
8904 msgid "B<CLOCK_REALTIME>"
8908 #: build/C/man2/timer_create.2:68
8909 msgid "A settable system-wide real-time clock."
8913 #: build/C/man2/timer_create.2:68
8915 msgid "B<CLOCK_MONOTONIC>"
8918 #. Note: the CLOCK_MONOTONIC_RAW clock added for clock_gettime()
8919 #. in 2.6.28 is not supported for POSIX timers -- mtk, Feb 2009
8921 #: build/C/man2/timer_create.2:75
8923 "A nonsettable monotonically increasing clock that measures time from some "
8924 "unspecified point in the past that does not change after system startup."
8928 #: build/C/man2/timer_create.2:75
8930 msgid "B<CLOCK_PROCESS_CPUTIME_ID> (since Linux 2.6.12)"
8934 #: build/C/man2/timer_create.2:79
8936 "A clock that measures (user and system) CPU time consumed by (all of the "
8937 "threads in) the calling process."
8941 #: build/C/man2/timer_create.2:79
8943 msgid "B<CLOCK_THREAD_CPUTIME_ID> (since Linux 2.6.12)"
8946 #. The CLOCK_MONOTONIC_RAW that was added in 2.6.28 can't be used
8947 #. to create a timer -- mtk, Feb 2009
8949 #: build/C/man2/timer_create.2:85
8951 "A clock that measures (user and system) CPU time consumed by the calling "
8956 #: build/C/man2/timer_create.2:94
8958 "As well as the above values, I<clockid> can be specified as the I<clockid> "
8959 "returned by a call to B<clock_getcpuclockid>(3) or "
8960 "B<pthread_getcpuclockid>(3)."
8964 #: build/C/man2/timer_create.2:103
8966 "The I<sevp> argument points to a I<sigevent> structure that specifies how "
8967 "the caller should be notified when the timer expires. For the definition "
8968 "and general details of this structure, see B<sigevent>(7)."
8972 #: build/C/man2/timer_create.2:107
8973 msgid "The I<sevp.sigev_notify> field can have the following values:"
8977 #: build/C/man2/timer_create.2:112
8979 "Don't asynchronously notify when the timer expires. Progress of the timer "
8980 "can be monitored using B<timer_gettime>(2)."
8984 #: build/C/man2/timer_create.2:130
8986 "Upon timer expiration, generate the signal I<sigev_signo> for the process. "
8987 "See B<sigevent>(7) for general details. The I<si_code> field of the "
8988 "I<siginfo_t> structure will be set to B<SI_TIMER>. At any point in time, at "
8989 "most one signal is queued to the process for a given timer; see "
8990 "B<timer_getoverrun>(2) for more details."
8994 #: build/C/man2/timer_create.2:138
8996 "Upon timer expiration, invoke I<sigev_notify_function> as if it were the "
8997 "start function of a new thread. See B<sigevent>(7) for details."
9001 #: build/C/man2/timer_create.2:152
9003 "As for B<SIGEV_SIGNAL>, but the signal is targeted at the thread whose ID is "
9004 "given in I<sigev_notify_thread_id>, which must be a thread in the same "
9005 "process as the caller. The I<sigev_notify_thread_id> field specifies a "
9006 "kernel thread ID, that is, the value returned by B<clone>(2) or "
9007 "B<gettid>(2). This flag is intended only for use by threading libraries."
9011 #: build/C/man2/timer_create.2:167
9013 "Specifying I<sevp> as NULL is equivalent to specifying a pointer to a "
9014 "I<sigevent> structure in which I<sigev_notify> is B<SIGEV_SIGNAL>, "
9015 "I<sigev_signo> is B<SIGALRM>, and I<sigev_value.sival_int> is the timer ID."
9019 #: build/C/man2/timer_create.2:175
9021 "On success, B<timer_create>() returns 0, and the ID of the new timer is "
9022 "placed in I<*timerid>. On failure, -1 is returned, and I<errno> is set to "
9023 "indicate the error."
9027 #: build/C/man2/timer_create.2:179
9028 msgid "Temporary error during kernel allocation of timer structures."
9032 #: build/C/man2/timer_create.2:187
9034 "Clock ID, I<sigev_notify>, I<sigev_signo>, or I<sigev_notify_thread_id> is "
9038 #. glibc layer: malloc()
9040 #: build/C/man2/timer_create.2:191
9041 msgid "Could not allocate memory."
9045 #: build/C/man2/timer_create.2:193 build/C/man2/timer_delete.2:67 build/C/man2/timer_getoverrun.2:97
9046 msgid "This system call is available since Linux 2.6."
9050 #: build/C/man2/timer_create.2:198
9051 msgid "A program may create multiple interval timers using B<timer_create>()."
9055 #: build/C/man2/timer_create.2:203
9057 "Timers are not inherited by the child of a B<fork>(2), and are disarmed and "
9058 "deleted during an B<execve>(2)."
9062 #: build/C/man2/timer_create.2:211
9064 "The kernel preallocates a \"queued real-time signal\" for each timer created "
9065 "using B<timer_create>(). Consequently, the number of timers is limited by "
9066 "the B<RLIMIT_SIGPENDING> resource limit (see B<setrlimit>(2))."
9070 #: build/C/man2/timer_create.2:216
9072 "The timers created by B<timer_create>() are commonly known as \"POSIX "
9073 "(interval) timers\". The POSIX timers API consists of the following "
9078 #: build/C/man2/timer_create.2:219
9079 msgid "B<timer_create>(): Create a timer."
9083 #: build/C/man2/timer_create.2:222
9084 msgid "B<timer_settime>(2): Arm (start) or disarm (stop) a timer."
9088 #: build/C/man2/timer_create.2:226
9090 "B<timer_gettime>(2): Fetch the time remaining until the next expiration of a "
9091 "timer, along with the interval setting of the timer."
9095 #: build/C/man2/timer_create.2:229
9097 "B<timer_getoverrun>(2): Return the overrun count for the last timer "
9102 #: build/C/man2/timer_create.2:232
9103 msgid "B<timer_delete>(2): Disarm and delete a timer."
9107 #: build/C/man2/timer_create.2:235
9109 "Part of the implementation of the POSIX timers API is provided by glibc. In "
9114 #: build/C/man2/timer_create.2:239
9116 "The functionality for B<SIGEV_THREAD> is implemented within glibc, rather "
9120 #. See the glibc source file kernel-posix-timers.h for the structure
9121 #. that glibc uses to map user-space timer IDs to kernel timer IDs
9122 #. The kernel-level timer ID is exposed via siginfo.si_tid.
9124 #: build/C/man2/timer_create.2:245
9126 "The timer IDs presented at user level are maintained by glibc, which maps "
9127 "these IDs to the timer IDs employed by the kernel."
9131 #: build/C/man2/timer_create.2:253
9133 "The POSIX timers system calls first appeared in Linux 2.6. Prior to this, "
9134 "glibc provided an incomplete user-space implementation (B<CLOCK_REALTIME> "
9135 "timers only) using POSIX threads, and current glibc falls back to this "
9136 "implementation on systems running pre-2.6 Linux kernels."
9140 #: build/C/man2/timer_create.2:261
9142 "Since Linux 3.10, the I</proc/[pid]/timers> file can be used to list the "
9143 "POSIX timers for the process with PID I<pid>. See B<proc>(5) for further "
9148 #: build/C/man2/timer_create.2:273
9150 "The program below takes two arguments: a sleep period in seconds, and a "
9151 "timer frequency in nanoseconds. The program establishes a handler for the "
9152 "signal it uses for the timer, blocks that signal, creates and arms a timer "
9153 "that expires with the given frequency, sleeps for the specified number of "
9154 "seconds, and then unblocks the timer signal. Assuming that the timer "
9155 "expired at least once while the program slept, the signal handler will be "
9156 "invoked, and the handler displays some information about the timer "
9157 "notification. The program terminates after one invocation of the signal "
9162 #: build/C/man2/timer_create.2:278
9164 "In the following example run, the program sleeps for 1 second, after "
9165 "creating a timer that has a frequency of 100 nanoseconds. By the time the "
9166 "signal is unblocked and delivered, there have been around ten million "
9171 #: build/C/man2/timer_create.2:290
9174 "$ B<./a.out 1 100>\n"
9175 "Establishing handler for signal 34\n"
9176 "Blocking signal 34\n"
9177 "timer ID is 0x804c008\n"
9178 "Sleeping for 1 seconds\n"
9179 "Unblocking signal 34\n"
9180 "Caught signal 34\n"
9181 " sival_ptr = 0xbfb174f4; *sival_ptr = 0x804c008\n"
9182 " overrun count = 10004886\n"
9186 #: build/C/man2/timer_create.2:300
9189 "#include E<lt>stdlib.hE<gt>\n"
9190 "#include E<lt>unistd.hE<gt>\n"
9191 "#include E<lt>stdio.hE<gt>\n"
9192 "#include E<lt>signal.hE<gt>\n"
9193 "#include E<lt>time.hE<gt>\n"
9197 #: build/C/man2/timer_create.2:303
9200 "#define CLOCKID CLOCK_REALTIME\n"
9201 "#define SIG SIGRTMIN\n"
9205 #: build/C/man2/timer_create.2:306
9208 "#define errExit(msg) do { perror(msg); exit(EXIT_FAILURE); \\e\n"
9213 #: build/C/man2/timer_create.2:312
9217 "print_siginfo(siginfo_t *si)\n"
9224 #: build/C/man2/timer_create.2:314
9226 msgid " tidp = si-E<gt>si_value.sival_ptr;\n"
9230 #: build/C/man2/timer_create.2:317
9233 " printf(\" sival_ptr = %p; \", si-E<gt>si_value.sival_ptr);\n"
9234 " printf(\" *sival_ptr = 0x%lx\\en\", (long) *tidp);\n"
9238 #: build/C/man2/timer_create.2:324
9241 " or = timer_getoverrun(*tidp);\n"
9243 " errExit(\"timer_getoverrun\");\n"
9245 " printf(\" overrun count = %d\\en\", or);\n"
9250 #: build/C/man2/timer_create.2:331
9254 "handler(int sig, siginfo_t *si, void *uc)\n"
9256 " /* Note: calling printf() from a signal handler is not\n"
9257 " strictly correct, since printf() is not async-signal-safe;\n"
9258 " see signal(7) */\n"
9262 #: build/C/man2/timer_create.2:336
9265 " printf(\"Caught signal %d\\en\", sig);\n"
9266 " print_siginfo(si);\n"
9267 " signal(sig, SIG_IGN);\n"
9272 #: build/C/man2/timer_create.2:346
9276 "main(int argc, char *argv[])\n"
9278 " timer_t timerid;\n"
9279 " struct sigevent sev;\n"
9280 " struct itimerspec its;\n"
9281 " long long freq_nanosecs;\n"
9283 " struct sigaction sa;\n"
9287 #: build/C/man2/timer_create.2:352
9290 " if (argc != 3) {\n"
9291 " fprintf(stderr, \"Usage: %s E<lt>sleep-secsE<gt> "
9292 "E<lt>freq-nanosecsE<gt>\\en\",\n"
9294 " exit(EXIT_FAILURE);\n"
9299 #: build/C/man2/timer_create.2:354
9301 msgid " /* Establish handler for timer signal */\n"
9305 #: build/C/man2/timer_create.2:361
9308 " printf(\"Establishing handler for signal %d\\en\", SIG);\n"
9309 " sa.sa_flags = SA_SIGINFO;\n"
9310 " sa.sa_sigaction = handler;\n"
9311 " sigemptyset(&sa.sa_mask);\n"
9312 " if (sigaction(SIG, &sa, NULL) == -1)\n"
9313 " errExit(\"sigaction\");\n"
9317 #: build/C/man2/timer_create.2:363
9319 msgid " /* Block timer signal temporarily */\n"
9323 #: build/C/man2/timer_create.2:369
9326 " printf(\"Blocking signal %d\\en\", SIG);\n"
9327 " sigemptyset(&mask);\n"
9328 " sigaddset(&mask, SIG);\n"
9329 " if (sigprocmask(SIG_SETMASK, &mask, NULL) == -1)\n"
9330 " errExit(\"sigprocmask\");\n"
9334 #: build/C/man2/timer_create.2:371
9336 msgid " /* Create the timer */\n"
9340 #: build/C/man2/timer_create.2:377
9343 " sev.sigev_notify = SIGEV_SIGNAL;\n"
9344 " sev.sigev_signo = SIG;\n"
9345 " sev.sigev_value.sival_ptr = &timerid;\n"
9346 " if (timer_create(CLOCKID, &sev, &timerid) == -1)\n"
9347 " errExit(\"timer_create\");\n"
9351 #: build/C/man2/timer_create.2:379
9353 msgid " printf(\"timer ID is 0x%lx\\en\", (long) timerid);\n"
9357 #: build/C/man2/timer_create.2:381
9359 msgid " /* Start the timer */\n"
9363 #: build/C/man2/timer_create.2:387
9366 " freq_nanosecs = atoll(argv[2]);\n"
9367 " its.it_value.tv_sec = freq_nanosecs / 1000000000;\n"
9368 " its.it_value.tv_nsec = freq_nanosecs % 1000000000;\n"
9369 " its.it_interval.tv_sec = its.it_value.tv_sec;\n"
9370 " its.it_interval.tv_nsec = its.it_value.tv_nsec;\n"
9374 #: build/C/man2/timer_create.2:390
9377 " if (timer_settime(timerid, 0, &its, NULL) == -1)\n"
9378 " errExit(\"timer_settime\");\n"
9382 #: build/C/man2/timer_create.2:393
9385 " /* Sleep for a while; meanwhile, the timer may expire\n"
9386 " multiple times */\n"
9390 #: build/C/man2/timer_create.2:396
9393 " printf(\"Sleeping for %d seconds\\en\", atoi(argv[1]));\n"
9394 " sleep(atoi(argv[1]));\n"
9398 #: build/C/man2/timer_create.2:399
9401 " /* Unlock the timer signal, so that timer notification\n"
9402 " can be delivered */\n"
9406 #: build/C/man2/timer_create.2:403
9409 " printf(\"Unblocking signal %d\\en\", SIG);\n"
9410 " if (sigprocmask(SIG_UNBLOCK, &mask, NULL) == -1)\n"
9411 " errExit(\"sigprocmask\");\n"
9415 #: build/C/man2/timer_create.2:406 build/C/man2/timerfd_create.2:540
9418 " exit(EXIT_SUCCESS);\n"
9423 #: build/C/man2/timer_create.2:422
9425 "B<clock_gettime>(2), B<setitimer>(2), B<timer_delete>(2), "
9426 "B<timer_getoverrun>(2), B<timer_settime>(2), B<timerfd_create>(2), "
9427 "B<clock_getcpuclockid>(3), B<pthread_getcpuclockid>(3), B<pthreads>(7), "
9428 "B<sigevent>(7), B<signal>(7), B<time>(7)"
9432 #: build/C/man2/timer_delete.2:26
9434 msgid "TIMER_DELETE"
9438 #: build/C/man2/timer_delete.2:26 build/C/man2/timer_getoverrun.2:26
9444 #: build/C/man2/timer_delete.2:29
9445 msgid "timer_delete - delete a POSIX per-process timer"
9449 #: build/C/man2/timer_delete.2:32 build/C/man2/timer_getoverrun.2:32 build/C/man2/timer_settime.2:33
9451 msgid "B<#include E<lt>time.hE<gt>>\n"
9455 #: build/C/man2/timer_delete.2:34
9457 msgid "B<int timer_delete(timer_t >I<timerid>B<);>\n"
9461 #: build/C/man2/timer_delete.2:45
9462 msgid "B<timer_delete>(): _POSIX_C_SOURCE\\ E<gt>=\\ 199309L"
9466 #: build/C/man2/timer_delete.2:53
9468 "B<timer_delete>() deletes the timer whose ID is given in I<timerid>. If "
9469 "the timer was armed at the time of this call, it is disarmed before being "
9470 "deleted. The treatment of any pending signal generated by the deleted timer "
9475 #: build/C/man2/timer_delete.2:60
9477 "On success, B<timer_delete>() returns 0. On failure, -1 is returned, and "
9478 "I<errno> is set to indicate the error."
9482 #: build/C/man2/timer_delete.2:65 build/C/man2/timer_getoverrun.2:95
9483 msgid "I<timerid> is not a valid timer ID."
9487 #: build/C/man2/timer_delete.2:75
9489 "B<clock_gettime>(2), B<timer_create>(2), B<timer_getoverrun>(2), "
9490 "B<timer_settime>(2), B<time>(7)"
9494 #: build/C/man2/timer_getoverrun.2:26
9496 msgid "TIMER_GETOVERRUN"
9500 #: build/C/man2/timer_getoverrun.2:29
9501 msgid "timer_getoverrun - get overrun count for a POSIX per-process timer"
9505 #: build/C/man2/timer_getoverrun.2:34
9507 msgid "B<int timer_getoverrun(timer_t >I<timerid>B<);>\n"
9511 #: build/C/man2/timer_getoverrun.2:45
9512 msgid "B<timer_getoverrun>(): _POSIX_C_SOURCE\\ E<gt>=\\ 199309L"
9516 #: build/C/man2/timer_getoverrun.2:56
9518 "B<timer_getoverrun>() returns the \"overrun count\" for the timer referred "
9519 "to by I<timerid>. An application can use the overrun count to accurately "
9520 "calculate the number of timer expirations that would have occurred over a "
9521 "given time interval. Timer overruns can occur both when receiving "
9522 "expiration notifications via signals (B<SIGEV_SIGNAL>), and via threads "
9523 "(B<SIGEV_THREAD>)."
9527 #: build/C/man2/timer_getoverrun.2:76
9529 "When expiration notifications are delivered via a signal, overruns can occur "
9530 "as follows. Regardless of whether or not a real-time signal is used for "
9531 "timer notifications, the system queues at most one signal per timer. (This "
9532 "is the behavior specified by POSIX.1-2001. The alternative, queuing one "
9533 "signal for each timer expiration, could easily result in overflowing the "
9534 "allowed limits for queued signals on the system.) Because of system "
9535 "scheduling delays, or because the signal may be temporarily blocked, there "
9536 "can be a delay between the time when the notification signal is generated "
9537 "and the time when it is delivered (e.g., caught by a signal handler) or "
9538 "accepted (e.g., using B<sigwaitinfo>(2)). In this interval, further timer "
9539 "expirations may occur. The timer overrun count is the number of additional "
9540 "timer expirations that occurred between the time when the signal was "
9541 "generated and when it was delivered or accepted."
9545 #: build/C/man2/timer_getoverrun.2:82
9547 "Timer overruns can also occur when expiration notifications are delivered "
9548 "via invocation of a thread, since there may be an arbitrary delay between an "
9549 "expiration of the timer and the invocation of the notification thread, and "
9550 "in that delay interval, additional timer expirations may occur."
9554 #: build/C/man2/timer_getoverrun.2:90
9556 "On success, B<timer_getoverrun>() returns the overrun count of the "
9557 "specified timer; this count may be 0 if no overruns have occurred. On "
9558 "failure, -1 is returned, and I<errno> is set to indicate the error."
9562 #: build/C/man2/timer_getoverrun.2:111
9564 "When timer notifications are delivered via signals (B<SIGEV_SIGNAL>), on "
9565 "Linux it is also possible to obtain the overrun count via the I<si_overrun> "
9566 "field of the I<siginfo_t> structure (see B<sigaction>(2)). This allows an "
9567 "application to avoid the overhead of making a system call to obtain the "
9568 "overrun count, but is a nonportable extension to POSIX.1-2001."
9571 #. FIXME . Austin bug filed, 11 Feb 09
9573 #: build/C/man2/timer_getoverrun.2:115
9575 "POSIX.1-2001 discusses timer overruns only in the context of timer "
9576 "notifications using signals."
9579 #. Bug filed: http://bugzilla.kernel.org/show_bug.cgi?id=12665
9580 #. http://thread.gmane.org/gmane.linux.kernel/113276/
9582 #: build/C/man2/timer_getoverrun.2:128
9584 "POSIX.1-2001 specifies that if the timer overrun count is equal to or "
9585 "greater than an implementation-defined maximum, B<DELAYTIMER_MAX>, then "
9586 "B<timer_getoverrun>() should return B<DELAYTIMER_MAX>. However, Linux does "
9587 "not implement this feature: instead, if the timer overrun value exceeds the "
9588 "maximum representable integer, the counter cycles, starting once more from "
9593 #: build/C/man2/timer_getoverrun.2:131 build/C/man2/timer_settime.2:212
9594 msgid "See B<timer_create>(2)."
9598 #: build/C/man2/timer_getoverrun.2:141
9600 "B<clock_gettime>(2), B<sigaction>(2), B<signalfd>(2), B<sigwaitinfo>(2), "
9601 "B<timer_create>(2), B<timer_delete>(2), B<timer_settime>(2), B<signal>(7), "
9606 #: build/C/man2/timer_settime.2:26
9608 msgid "TIMER_SETTIME"
9612 #: build/C/man2/timer_settime.2:26
9618 #: build/C/man2/timer_settime.2:30
9620 "timer_settime, timer_gettime - arm/disarm and fetch state of POSIX "
9625 #: build/C/man2/timer_settime.2:38
9628 "B<int timer_settime(timer_t >I<timerid>B<, int >I<flags>B<,>\n"
9629 "B< const struct itimerspec *>I<new_value>B<,>\n"
9630 "B< struct itimerspec * >I<old_value>B<);>\n"
9631 "B<int timer_gettime(timer_t >I<timerid>B<, struct itimerspec "
9632 "*>I<curr_value>B<);>\n"
9636 #: build/C/man2/timer_settime.2:50
9637 msgid "B<timer_settime>(), B<timer_gettime>(): _POSIX_C_SOURCE\\ E<gt>=\\ 199309L"
9641 #: build/C/man2/timer_settime.2:63
9643 "B<timer_settime>() arms or disarms the timer identified by I<timerid>. The "
9644 "I<new_value> argument is pointer to an I<itimerspec> structure that "
9645 "specifies the new initial value and the new interval for the timer. The "
9646 "I<itimerspec> structure is defined as follows:"
9650 #: build/C/man2/timer_settime.2:70 build/C/man2/timerfd_create.2:128
9653 "struct timespec {\n"
9654 " time_t tv_sec; /* Seconds */\n"
9655 " long tv_nsec; /* Nanoseconds */\n"
9660 #: build/C/man2/timer_settime.2:75
9663 "struct itimerspec {\n"
9664 " struct timespec it_interval; /* Timer interval */\n"
9665 " struct timespec it_value; /* Initial expiration */\n"
9670 #: build/C/man2/timer_settime.2:87
9672 "Each of the substructures of the I<itimerspec> structure is a I<timespec> "
9673 "structure that allows a time value to be specified in seconds and "
9674 "nanoseconds. These time values are measured according to the clock that was "
9675 "specified when the timer was created by B<timer_create>(2)."
9679 #: build/C/man2/timer_settime.2:101
9681 "If I<new_value-E<gt>it_value> specifies a nonzero value (i.e., either "
9682 "subfield is nonzero), then B<timer_settime>() arms (starts) the timer, "
9683 "setting it to initially expire at the given time. (If the timer was already "
9684 "armed, then the previous settings are overwritten.) If "
9685 "I<new_value-E<gt>it_value> specifies a zero value (i.e., both subfields are "
9686 "zero), then the timer is disarmed."
9690 #: build/C/man2/timer_settime.2:113
9692 "The I<new_value-E<gt>it_interval> field specifies the period of the timer, "
9693 "in seconds and nanoseconds. If this field is nonzero, then each time that "
9694 "an armed timer expires, the timer is reloaded from the value specified in "
9695 "I<new_value-E<gt>it_interval>. If I<new_value-E<gt>it_interval> specifies a "
9696 "zero value, then the timer expires just once, at the time specified by "
9700 #. By experiment: the overrun count is set correctly, for CLOCK_REALTIME.
9702 #: build/C/man2/timer_settime.2:134
9704 "By default, the initial expiration time specified in "
9705 "I<new_value-E<gt>it_value> is interpreted relative to the current time on "
9706 "the timer's clock at the time of the call. This can be modified by "
9707 "specifying B<TIMER_ABSTIME> in I<flags>, in which case "
9708 "I<new_value-E<gt>it_value> is interpreted as an absolute value as measured "
9709 "on the timer's clock; that is, the timer will expire when the clock value "
9710 "reaches the value specified by I<new_value-E<gt>it_value>. If the specified "
9711 "absolute time has already passed, then the timer expires immediately, and "
9712 "the overrun count (see B<timer_getoverrun>(2)) will be set correctly."
9715 #. Similar remarks might apply with respect to process and thread CPU time
9716 #. clocks, but these clocks are not currently (2.6.28) settable on Linux.
9718 #: build/C/man2/timer_settime.2:144
9720 "If the value of the B<CLOCK_REALTIME> clock is adjusted while an absolute "
9721 "timer based on that clock is armed, then the expiration of the timer will be "
9722 "appropriately adjusted. Adjustments to the B<CLOCK_REALTIME> clock have no "
9723 "effect on relative timers based on that clock."
9727 #: build/C/man2/timer_settime.2:153
9729 "If I<old_value> is not NULL, then it points to a buffer that is used to "
9730 "return the previous interval of the timer (in I<old_value-E<gt>it_interval>) "
9731 "and the amount of time until the timer would previously have next expired "
9732 "(in I<old_value-E<gt>it_value>)."
9736 #: build/C/man2/timer_settime.2:173
9738 "B<timer_gettime>() returns the time until next expiration, and the "
9739 "interval, for the timer specified by I<timerid>, in the buffer pointed to by "
9740 "I<curr_value>. The time remaining until the next timer expiration is "
9741 "returned in I<curr_value-E<gt>it_value>; this is always a relative value, "
9742 "regardless of whether the B<TIMER_ABSTIME> flag was used when arming the "
9743 "timer. If the value returned in I<curr_value-E<gt>it_value> is zero, then "
9744 "the timer is currently disarmed. The timer interval is returned in "
9745 "I<curr_value-E<gt>it_interval>. If the value returned in "
9746 "I<curr_value-E<gt>it_interval> is zero, then this is a \"one-shot\" timer."
9750 #: build/C/man2/timer_settime.2:182
9752 "On success, B<timer_settime>() and B<timer_gettime>() return 0. On error, "
9753 "-1 is returned, and I<errno> is set to indicate the error."
9757 #: build/C/man2/timer_settime.2:184
9758 msgid "These functions may fail with the following errors:"
9762 #: build/C/man2/timer_settime.2:191
9763 msgid "I<new_value>, I<old_value>, or I<curr_value> is not a valid pointer."
9766 #. FIXME . eventually: invalid value in flags
9768 #: build/C/man2/timer_settime.2:196
9769 msgid "I<timerid> is invalid."
9773 #: build/C/man2/timer_settime.2:199
9774 msgid "B<timer_settime>() may fail with the following errors:"
9778 #: build/C/man2/timer_settime.2:205
9780 "I<new_value.it_value> is negative; or I<new_value.it_value.tv_nsec> is "
9781 "negative or greater than 999,999,999."
9785 #: build/C/man2/timer_settime.2:207
9786 msgid "These system calls are available since Linux 2.6."
9790 #: build/C/man2/timer_settime.2:216
9791 msgid "B<timer_create>(2), B<timer_getoverrun>(2), B<time>(7)"
9795 #: build/C/man2/timerfd_create.2:21
9797 msgid "TIMERFD_CREATE"
9801 #: build/C/man2/timerfd_create.2:21
9807 #: build/C/man2/timerfd_create.2:25
9809 "timerfd_create, timerfd_settime, timerfd_gettime - timers that notify via "
9814 #: build/C/man2/timerfd_create.2:28
9816 msgid "B<#include E<lt>sys/timerfd.hE<gt>>\n"
9820 #: build/C/man2/timerfd_create.2:30
9822 msgid "B<int timerfd_create(int >I<clockid>B<, int >I<flags>B<);>\n"
9826 #: build/C/man2/timerfd_create.2:34
9829 "B<int timerfd_settime(int >I<fd>B<, int >I<flags>B<,>\n"
9830 "B< const struct itimerspec *>I<new_value>B<,>\n"
9831 "B< struct itimerspec *>I<old_value>B<);>\n"
9835 #: build/C/man2/timerfd_create.2:36
9837 msgid "B<int timerfd_gettime(int >I<fd>B<, struct itimerspec *>I<curr_value>B<);>\n"
9841 #: build/C/man2/timerfd_create.2:49
9843 "These system calls create and operate on a timer that delivers timer "
9844 "expiration notifications via a file descriptor. They provide an alternative "
9845 "to the use of B<setitimer>(2) or B<timer_create>(2), with the advantage "
9846 "that the file descriptor may be monitored by B<select>(2), B<poll>(2), and "
9851 #: build/C/man2/timerfd_create.2:61
9853 "The use of these three system calls is analogous to the use of "
9854 "B<timer_create>(2), B<timer_settime>(2), and B<timer_gettime>(2). (There is "
9855 "no analog of B<timer_getoverrun>(2), since that functionality is provided by "
9856 "B<read>(2), as described below.)"
9860 #: build/C/man2/timerfd_create.2:61
9862 msgid "timerfd_create()"
9866 #: build/C/man2/timerfd_create.2:80
9868 "B<timerfd_create>() creates a new timer object, and returns a file "
9869 "descriptor that refers to that timer. The I<clockid> argument specifies the "
9870 "clock that is used to mark the progress of the timer, and must be either "
9871 "B<CLOCK_REALTIME> or B<CLOCK_MONOTONIC>. B<CLOCK_REALTIME> is a settable "
9872 "system-wide clock. B<CLOCK_MONOTONIC> is a nonsettable clock that is not "
9873 "affected by discontinuous changes in the system clock (e.g., manual changes "
9874 "to system time). The current value of each of these clocks can be retrieved "
9875 "using B<clock_gettime>(2)."
9879 #: build/C/man2/timerfd_create.2:85
9881 "Starting with Linux 2.6.27, the following values may be bitwise ORed in "
9882 "I<flags> to change the behavior of B<timerfd_create>():"
9886 #: build/C/man2/timerfd_create.2:85
9888 msgid "B<TFD_NONBLOCK>"
9892 #: build/C/man2/timerfd_create.2:93
9894 msgid "B<TFD_CLOEXEC>"
9898 #: build/C/man2/timerfd_create.2:107
9900 "In Linux versions up to and including 2.6.26, I<flags> must be specified as "
9905 #: build/C/man2/timerfd_create.2:107
9907 msgid "timerfd_settime()"
9911 #: build/C/man2/timerfd_create.2:112
9913 "B<timerfd_settime>() arms (starts) or disarms (stops) the timer referred "
9914 "to by the file descriptor I<fd>."
9918 #: build/C/man2/timerfd_create.2:121
9920 "The I<new_value> argument specifies the initial expiration and interval for "
9921 "the timer. The I<itimer> structure used for this argument contains two "
9922 "fields, each of which is in turn a structure of type I<timespec>:"
9926 #: build/C/man2/timerfd_create.2:133
9929 "struct itimerspec {\n"
9930 " struct timespec it_interval; /* Interval for periodic timer */\n"
9931 " struct timespec it_value; /* Initial expiration */\n"
9936 #: build/C/man2/timerfd_create.2:145
9938 "I<new_value.it_value> specifies the initial expiration of the timer, in "
9939 "seconds and nanoseconds. Setting either field of I<new_value.it_value> to a "
9940 "nonzero value arms the timer. Setting both fields of I<new_value.it_value> "
9941 "to zero disarms the timer."
9945 #: build/C/man2/timerfd_create.2:154
9947 "Setting one or both fields of I<new_value.it_interval> to nonzero values "
9948 "specifies the period, in seconds and nanoseconds, for repeated timer "
9949 "expirations after the initial expiration. If both fields of "
9950 "I<new_value.it_interval> are zero, the timer expires just once, at the time "
9951 "specified by I<new_value.it_value>."
9955 #: build/C/man2/timerfd_create.2:170
9957 "The I<flags> argument is either 0, to start a relative timer "
9958 "(I<new_value.it_value> specifies a time relative to the current value of the "
9959 "clock specified by I<clockid>), or B<TFD_TIMER_ABSTIME>, to start an "
9960 "absolute timer (I<new_value.it_value> specifies an absolute time for the "
9961 "clock specified by I<clockid>; that is, the timer will expire when the value "
9962 "of that clock reaches the value specified in I<new_value.it_value>)."
9966 #: build/C/man2/timerfd_create.2:181
9968 "If the I<old_value> argument is not NULL, then the I<itimerspec> structure "
9969 "that it points to is used to return the setting of the timer that was "
9970 "current at the time of the call; see the description of B<timerfd_gettime>() "
9975 #: build/C/man2/timerfd_create.2:181
9977 msgid "timerfd_gettime()"
9981 #: build/C/man2/timerfd_create.2:190
9983 "B<timerfd_gettime>() returns, in I<curr_value>, an I<itimerspec> structure "
9984 "that contains the current setting of the timer referred to by the file "
9989 #: build/C/man2/timerfd_create.2:200
9991 "The I<it_value> field returns the amount of time until the timer will next "
9992 "expire. If both fields of this structure are zero, then the timer is "
9993 "currently disarmed. This field always contains a relative value, regardless "
9994 "of whether the B<TFD_TIMER_ABSTIME> flag was specified when setting the "
9999 #: build/C/man2/timerfd_create.2:207
10001 "The I<it_interval> field returns the interval of the timer. If both fields "
10002 "of this structure are zero, then the timer is set to expire just once, at "
10003 "the time specified by I<curr_value.it_value>."
10007 #: build/C/man2/timerfd_create.2:207
10009 msgid "Operating on a timer file descriptor"
10012 #. type: Plain text
10013 #: build/C/man2/timerfd_create.2:211
10015 "The file descriptor returned by B<timerfd_create>() supports the following "
10019 #. type: Plain text
10020 #: build/C/man2/timerfd_create.2:225
10022 "If the timer has already expired one or more times since its settings were "
10023 "last modified using B<timerfd_settime>(), or since the last successful "
10024 "B<read>(2), then the buffer given to B<read>(2) returns an unsigned 8-byte "
10025 "integer (I<uint64_t>) containing the number of expirations that have "
10026 "occurred. (The returned value is in host byte order\\(emthat is, the native "
10027 "byte order for integers on the host machine.)"
10030 #. type: Plain text
10031 #: build/C/man2/timerfd_create.2:238
10033 "If no timer expirations have occurred at the time of the B<read>(2), then "
10034 "the call either blocks until the next timer expiration, or fails with the "
10035 "error B<EAGAIN> if the file descriptor has been made nonblocking (via the "
10036 "use of the B<fcntl>(2) B<F_SETFL> operation to set the B<O_NONBLOCK> flag)."
10039 #. type: Plain text
10040 #: build/C/man2/timerfd_create.2:244
10042 "A B<read>(2) will fail with the error B<EINVAL> if the size of the supplied "
10043 "buffer is less than 8 bytes."
10046 #. type: Plain text
10047 #: build/C/man2/timerfd_create.2:255
10049 "The file descriptor is readable (the B<select>(2) I<readfds> argument; the "
10050 "B<poll>(2) B<POLLIN> flag) if one or more timer expirations have occurred."
10053 #. type: Plain text
10054 #: build/C/man2/timerfd_create.2:262
10056 "The file descriptor also supports the other file-descriptor multiplexing "
10057 "APIs: B<pselect>(2), B<ppoll>(2), and B<epoll>(7)."
10060 #. type: Plain text
10061 #: build/C/man2/timerfd_create.2:269
10063 "When the file descriptor is no longer required it should be closed. When "
10064 "all file descriptors associated with the same timer object have been closed, "
10065 "the timer is disarmed and its resources are freed by the kernel."
10068 #. type: Plain text
10069 #: build/C/man2/timerfd_create.2:281
10071 "After a B<fork>(2), the child inherits a copy of the file descriptor created "
10072 "by B<timerfd_create>(). The file descriptor refers to the same underlying "
10073 "timer object as the corresponding file descriptor in the parent, and "
10074 "B<read>(2)s in the child will return information about expirations of the "
10078 #. type: Plain text
10079 #: build/C/man2/timerfd_create.2:287
10081 "A file descriptor created by B<timerfd_create>() is preserved across "
10082 "B<execve>(2), and continues to generate timer expirations if the timer was "
10086 #. type: Plain text
10087 #: build/C/man2/timerfd_create.2:294
10089 "On success, B<timerfd_create>() returns a new file descriptor. On error, "
10090 "-1 is returned and I<errno> is set to indicate the error."
10093 #. type: Plain text
10094 #: build/C/man2/timerfd_create.2:302
10096 "B<timerfd_settime>() and B<timerfd_gettime>() return 0 on success; on "
10097 "error they return -1, and set I<errno> to indicate the error."
10100 #. type: Plain text
10101 #: build/C/man2/timerfd_create.2:305
10102 msgid "B<timerfd_create>() can fail with the following errors:"
10105 #. type: Plain text
10106 #: build/C/man2/timerfd_create.2:313
10107 msgid "The I<clockid> argument is neither B<CLOCK_MONOTONIC> nor B<CLOCK_REALTIME>;"
10110 #. type: Plain text
10111 #: build/C/man2/timerfd_create.2:333
10112 msgid "There was insufficient kernel memory to create the timer."
10115 #. type: Plain text
10116 #: build/C/man2/timerfd_create.2:338
10118 "B<timerfd_settime>() and B<timerfd_gettime>() can fail with the following "
10122 #. type: Plain text
10123 #: build/C/man2/timerfd_create.2:342
10124 msgid "I<fd> is not a valid file descriptor."
10127 #. type: Plain text
10128 #: build/C/man2/timerfd_create.2:353
10129 msgid "I<fd> is not a valid timerfd file descriptor."
10132 #. type: Plain text
10133 #: build/C/man2/timerfd_create.2:356
10134 msgid "B<timerfd_settime>() can also fail with the following errors:"
10137 #. type: Plain text
10138 #: build/C/man2/timerfd_create.2:362
10140 "I<new_value> is not properly initialized (one of the I<tv_nsec> falls "
10141 "outside the range zero to 999,999,999)."
10144 #. This case only checked since 2.6.29, and 2.2.2[78].some-stable-version.
10145 #. In older kernel versions, no check was made for invalid flags.
10146 #. type: Plain text
10147 #: build/C/man2/timerfd_create.2:368
10148 msgid "I<flags> is invalid."
10151 #. type: Plain text
10152 #: build/C/man2/timerfd_create.2:371
10154 "These system calls are available on Linux since kernel 2.6.25. Library "
10155 "support is provided by glibc since version 2.8."
10159 #. type: Plain text
10160 #: build/C/man2/timerfd_create.2:379
10162 "Currently, B<timerfd_create>() supports fewer types of clock IDs than "
10163 "B<timer_create>(2)."
10166 #. type: Plain text
10167 #: build/C/man2/timerfd_create.2:388
10169 "The following program creates a timer and then monitors its progress. The "
10170 "program accepts up to three command-line arguments. The first argument "
10171 "specifies the number of seconds for the initial expiration of the timer. "
10172 "The second argument specifies the interval for the timer, in seconds. The "
10173 "third argument specifies the number of times the program should allow the "
10174 "timer to expire before terminating. The second and third command-line "
10175 "arguments are optional."
10178 #. type: Plain text
10179 #: build/C/man2/timerfd_create.2:390 build/C/man2/wait.2:570
10180 msgid "The following shell session demonstrates the use of the program:"
10183 #. type: Plain text
10184 #: build/C/man2/timerfd_create.2:405
10187 "$B< a.out 3 1 100>\n"
10188 "0.000: timer started\n"
10189 "3.000: read: 1; total=1\n"
10190 "4.000: read: 1; total=2\n"
10191 "B<^Z > # type control-Z to suspend the program\n"
10192 "[1]+ Stopped ./timerfd3_demo 3 1 100\n"
10193 "$ B<fg> # Resume execution after a few seconds\n"
10195 "9.660: read: 5; total=7\n"
10196 "10.000: read: 1; total=8\n"
10197 "11.000: read: 1; total=9\n"
10198 "B<^C > # type control-C to suspend the program\n"
10201 #. The commented out code here is what we currently need until
10202 #. the required stuff is in glibc
10205 #. /* Link with -lrt */
10206 #. #define _GNU_SOURCE
10207 #. #include <sys/syscall.h>
10208 #. #include <unistd.h>
10209 #. #include <time.h>
10210 #. #if defined(__i386__)
10211 #. #define __NR_timerfd_create 322
10212 #. #define __NR_timerfd_settime 325
10213 #. #define __NR_timerfd_gettime 326
10217 #. timerfd_create(int clockid, int flags)
10219 #. return syscall(__NR_timerfd_create, clockid, flags);
10223 #. timerfd_settime(int fd, int flags, struct itimerspec *new_value,
10224 #. struct itimerspec *curr_value)
10226 #. return syscall(__NR_timerfd_settime, fd, flags, new_value,
10231 #. timerfd_gettime(int fd, struct itimerspec *curr_value)
10233 #. return syscall(__NR_timerfd_gettime, fd, curr_value);
10236 #. #define TFD_TIMER_ABSTIME (1 << 0)
10238 #. ////////////////////////////////////////////////////////////
10239 #. type: Plain text
10240 #: build/C/man2/timerfd_create.2:454
10243 "#include E<lt>sys/timerfd.hE<gt>\n"
10244 "#include E<lt>time.hE<gt>\n"
10245 "#include E<lt>unistd.hE<gt>\n"
10246 "#include E<lt>stdlib.hE<gt>\n"
10247 "#include E<lt>stdio.hE<gt>\n"
10248 "#include E<lt>stdint.hE<gt> /* Definition of uint64_t */\n"
10251 #. type: Plain text
10252 #: build/C/man2/timerfd_create.2:457
10255 "#define handle_error(msg) \\e\n"
10256 " do { perror(msg); exit(EXIT_FAILURE); } while (0)\n"
10259 #. type: Plain text
10260 #: build/C/man2/timerfd_create.2:465
10264 "print_elapsed_time(void)\n"
10266 " static struct timespec start;\n"
10267 " struct timespec curr;\n"
10268 " static int first_call = 1;\n"
10269 " int secs, nsecs;\n"
10272 #. type: Plain text
10273 #: build/C/man2/timerfd_create.2:471
10276 " if (first_call) {\n"
10277 " first_call = 0;\n"
10278 " if (clock_gettime(CLOCK_MONOTONIC, &start) == -1)\n"
10279 " handle_error(\"clock_gettime\");\n"
10283 #. type: Plain text
10284 #: build/C/man2/timerfd_create.2:474
10287 " if (clock_gettime(CLOCK_MONOTONIC, &curr) == -1)\n"
10288 " handle_error(\"clock_gettime\");\n"
10291 #. type: Plain text
10292 #: build/C/man2/timerfd_create.2:483
10295 " secs = curr.tv_sec - start.tv_sec;\n"
10296 " nsecs = curr.tv_nsec - start.tv_nsec;\n"
10297 " if (nsecs E<lt> 0) {\n"
10299 " nsecs += 1000000000;\n"
10301 " printf(\"%d.%03d: \", secs, (nsecs + 500000) / 1000000);\n"
10305 #. type: Plain text
10306 #: build/C/man2/timerfd_create.2:492
10310 "main(int argc, char *argv[])\n"
10312 " struct itimerspec new_value;\n"
10313 " int max_exp, fd;\n"
10314 " struct timespec now;\n"
10315 " uint64_t exp, tot_exp;\n"
10319 #. type: Plain text
10320 #: build/C/man2/timerfd_create.2:498
10323 " if ((argc != 2) && (argc != 4)) {\n"
10324 " fprintf(stderr, \"%s init-secs [interval-secs max-exp]\\en\",\n"
10326 " exit(EXIT_FAILURE);\n"
10330 #. type: Plain text
10331 #: build/C/man2/timerfd_create.2:501
10334 " if (clock_gettime(CLOCK_REALTIME, &now) == -1)\n"
10335 " handle_error(\"clock_gettime\");\n"
10338 #. type: Plain text
10339 #: build/C/man2/timerfd_create.2:504
10342 " /* Create a CLOCK_REALTIME absolute timer with initial\n"
10343 " expiration and interval as specified in command line */\n"
10346 #. type: Plain text
10347 #: build/C/man2/timerfd_create.2:515
10350 " new_value.it_value.tv_sec = now.tv_sec + atoi(argv[1]);\n"
10351 " new_value.it_value.tv_nsec = now.tv_nsec;\n"
10352 " if (argc == 2) {\n"
10353 " new_value.it_interval.tv_sec = 0;\n"
10356 " new_value.it_interval.tv_sec = atoi(argv[2]);\n"
10357 " max_exp = atoi(argv[3]);\n"
10359 " new_value.it_interval.tv_nsec = 0;\n"
10362 #. type: Plain text
10363 #: build/C/man2/timerfd_create.2:519
10366 " fd = timerfd_create(CLOCK_REALTIME, 0);\n"
10368 " handle_error(\"timerfd_create\");\n"
10371 #. type: Plain text
10372 #: build/C/man2/timerfd_create.2:522
10375 " if (timerfd_settime(fd, TFD_TIMER_ABSTIME, &new_value, NULL) == -1)\n"
10376 " handle_error(\"timerfd_settime\");\n"
10379 #. type: Plain text
10380 #: build/C/man2/timerfd_create.2:525
10383 " print_elapsed_time();\n"
10384 " printf(\"timer started\\en\");\n"
10387 #. type: Plain text
10388 #: build/C/man2/timerfd_create.2:530
10391 " for (tot_exp = 0; tot_exp E<lt> max_exp;) {\n"
10392 " s = read(fd, &exp, sizeof(uint64_t));\n"
10393 " if (s != sizeof(uint64_t))\n"
10394 " handle_error(\"read\");\n"
10397 #. type: Plain text
10398 #: build/C/man2/timerfd_create.2:537
10401 " tot_exp += exp;\n"
10402 " print_elapsed_time();\n"
10403 " printf(\"read: %llu; total=%llu\\en\",\n"
10404 " (unsigned long long) exp,\n"
10405 " (unsigned long long) tot_exp);\n"
10409 #. type: Plain text
10410 #: build/C/man2/timerfd_create.2:553
10412 "B<eventfd>(2), B<poll>(2), B<read>(2), B<select>(2), B<setitimer>(2), "
10413 "B<signalfd>(2), B<timer_create>(2), B<timer_gettime>(2), "
10414 "B<timer_settime>(2), B<epoll>(7), B<time>(7)"
10418 #: build/C/man2/tkill.2:29
10423 #. type: Plain text
10424 #: build/C/man2/tkill.2:32
10425 msgid "tkill, tgkill - send a signal to a thread"
10428 #. type: Plain text
10429 #: build/C/man2/tkill.2:35
10431 msgid "B<int tkill(int >I<tid>B<, int >I<sig>B<);>\n"
10434 #. type: Plain text
10435 #: build/C/man2/tkill.2:37
10437 msgid "B<int tgkill(int >I<tgid>B<, int >I<tid>B<, int >I<sig>B<);>\n"
10440 #. type: Plain text
10441 #: build/C/man2/tkill.2:54
10443 "B<tgkill>() sends the signal I<sig> to the thread with the thread ID I<tid> "
10444 "in the thread group I<tgid>. (By contrast, B<kill>(2) can be used to send "
10445 "a signal only to a process (i.e., thread group) as a whole, and the signal "
10446 "will be delivered to an arbitrary thread within that process.)"
10449 #. FIXME: Maybe say something about the following:
10450 #. http://sourceware.org/bugzilla/show_bug.cgi?id=12889
10451 #. Rich Felker <bugdal@aerifal.cx>
10452 #. There is a race condition in pthread_kill: it is possible that,
10453 #. between the time pthread_kill reads the pid/tid from the target
10454 #. thread descriptor and the time it makes the tgkill syscall,
10455 #. the target thread terminates and the same tid gets assigned
10456 #. to a new thread in the same process.
10458 #. (The tgkill syscall was designed to eliminate a similar race
10459 #. condition in tkill, but it only succeeded in eliminating races
10460 #. where the tid gets reused in a different process, and does not
10461 #. help if the same tid gets assigned to a new thread in the
10464 #. The only solution I can see is to introduce a mutex that ensures
10465 #. that a thread cannot exit while pthread_kill is being called on it.
10467 #. Note that in most real-world situations, like almost all race
10468 #. conditions, this one will be extremely rare. To make it
10469 #. measurable, one could exhaust all but 1-2 available pid values,
10470 #. possibly by lowering the max pid parameter in /proc, forcing
10471 #. the same tid to be reused rapidly.
10472 #. type: Plain text
10473 #: build/C/man2/tkill.2:85
10475 "B<tkill>() is an obsolete predecessor to B<tgkill>(). It allows only the "
10476 "target thread ID to be specified, which may result in the wrong thread being "
10477 "signaled if a thread terminates and its thread ID is recycled. Avoid using "
10478 "this system call."
10481 #. type: Plain text
10482 #: build/C/man2/tkill.2:92
10483 msgid "If I<tgid> is specified as -1, B<tgkill>() is equivalent to B<tkill>()."
10486 #. type: Plain text
10487 #: build/C/man2/tkill.2:95
10489 "These are the raw system call interfaces, meant for internal thread library "
10493 #. type: Plain text
10494 #: build/C/man2/tkill.2:103
10495 msgid "An invalid thread ID, thread group ID, or signal was specified."
10498 #. type: Plain text
10499 #: build/C/man2/tkill.2:108
10500 msgid "Permission denied. For the required permissions, see B<kill>(2)."
10503 #. type: Plain text
10504 #: build/C/man2/tkill.2:111
10505 msgid "No process with the specified thread ID (and thread group ID) exists."
10508 #. type: Plain text
10509 #: build/C/man2/tkill.2:116
10511 "B<tkill>() is supported since Linux 2.4.19 / 2.5.4. B<tgkill>() was added "
10515 #. type: Plain text
10516 #: build/C/man2/tkill.2:122
10518 "B<tkill>() and B<tgkill>() are Linux-specific and should not be used in "
10519 "programs that are intended to be portable."
10522 #. type: Plain text
10523 #: build/C/man2/tkill.2:128
10525 "See the description of B<CLONE_THREAD> in B<clone>(2) for an explanation of "
10529 #. type: Plain text
10530 #: build/C/man2/tkill.2:131
10532 "Glibc does not provide wrappers for these system calls; call them using "
10536 #. type: Plain text
10537 #: build/C/man2/tkill.2:136
10538 msgid "B<clone>(2), B<gettid>(2), B<kill>(2), B<rt_sigqueueinfo>(2)"
10542 #: build/C/man2/wait.2:49
10547 #. type: Plain text
10548 #: build/C/man2/wait.2:52
10549 msgid "wait, waitpid, waitid - wait for process to change state"
10552 #. type: Plain text
10553 #: build/C/man2/wait.2:54
10554 msgid "B<#include E<lt>sys/types.hE<gt>>"
10557 #. type: Plain text
10558 #: build/C/man2/wait.2:56
10559 msgid "B<#include E<lt>sys/wait.hE<gt>>"
10562 #. type: Plain text
10563 #: build/C/man2/wait.2:58
10564 msgid "B<pid_t wait(int *>I<status>B<);>"
10567 #. type: Plain text
10568 #: build/C/man2/wait.2:60
10569 msgid "B<pid_t waitpid(pid_t >I<pid>B<, int *>I<status>B<, int >I<options>B<);>"
10572 #. type: Plain text
10573 #: build/C/man2/wait.2:65
10576 "B<int waitid(idtype_t >I<idtype>B<, id_t >I<id>B<, siginfo_t *>I<infop>B<, "
10577 "int >I<options>B<);>\n"
10578 " /* This is the glibc and POSIX interface; see\n"
10579 " NOTES for information on the raw system call. */\n"
10582 #. type: Plain text
10583 #: build/C/man2/wait.2:74
10584 msgid "B<waitid>():"
10587 #. type: Plain text
10588 #: build/C/man2/wait.2:78
10590 "_SVID_SOURCE || _XOPEN_SOURCE\\ E<gt>=\\ 500 || _XOPEN_SOURCE\\ &&\\ "
10591 "_XOPEN_SOURCE_EXTENDED"
10594 #. type: Plain text
10595 #: build/C/man2/wait.2:93
10597 "All of these system calls are used to wait for state changes in a child of "
10598 "the calling process, and obtain information about the child whose state has "
10599 "changed. A state change is considered to be: the child terminated; the "
10600 "child was stopped by a signal; or the child was resumed by a signal. In the "
10601 "case of a terminated child, performing a wait allows the system to release "
10602 "the resources associated with the child; if a wait is not performed, then "
10603 "the terminated child remains in a \"zombie\" state (see NOTES below)."
10606 #. type: Plain text
10607 #: build/C/man2/wait.2:105
10609 "If a child has already changed state, then these calls return immediately. "
10610 "Otherwise, they block until either a child changes state or a signal handler "
10611 "interrupts the call (assuming that system calls are not automatically "
10612 "restarted using the B<SA_RESTART> flag of B<sigaction>(2)). In the "
10613 "remainder of this page, a child whose state has changed and which has not "
10614 "yet been waited upon by one of these system calls is termed I<waitable>."
10618 #: build/C/man2/wait.2:105
10620 msgid "wait() and waitpid()"
10623 #. type: Plain text
10624 #: build/C/man2/wait.2:113
10626 "The B<wait>() system call suspends execution of the calling process until "
10627 "one of its children terminates. The call I<wait(&status)> is equivalent to:"
10630 #. type: Plain text
10631 #: build/C/man2/wait.2:116
10633 msgid " waitpid(-1, &status, 0);\n"
10636 #. type: Plain text
10637 #: build/C/man2/wait.2:130
10639 "The B<waitpid>() system call suspends execution of the calling process "
10640 "until a child specified by I<pid> argument has changed state. By default, "
10641 "B<waitpid>() waits only for terminated children, but this behavior is "
10642 "modifiable via the I<options> argument, as described below."
10645 #. type: Plain text
10646 #: build/C/man2/wait.2:134
10647 msgid "The value of I<pid> can be:"
10651 #: build/C/man2/wait.2:134
10656 #. type: Plain text
10657 #: build/C/man2/wait.2:138
10659 "meaning wait for any child process whose process group ID is equal to the "
10660 "absolute value of I<pid>."
10664 #: build/C/man2/wait.2:138
10669 #. type: Plain text
10670 #: build/C/man2/wait.2:140
10671 msgid "meaning wait for any child process."
10675 #: build/C/man2/wait.2:140
10680 #. type: Plain text
10681 #: build/C/man2/wait.2:143
10683 "meaning wait for any child process whose process group ID is equal to that "
10684 "of the calling process."
10688 #: build/C/man2/wait.2:143
10693 #. type: Plain text
10694 #: build/C/man2/wait.2:147
10695 msgid "meaning wait for the child whose process ID is equal to the value of I<pid>."
10698 #. type: Plain text
10699 #: build/C/man2/wait.2:151
10700 msgid "The value of I<options> is an OR of zero or more of the following constants:"
10704 #: build/C/man2/wait.2:151 build/C/man2/wait.2:280
10709 #. type: Plain text
10710 #: build/C/man2/wait.2:154
10711 msgid "return immediately if no child has exited."
10715 #: build/C/man2/wait.2:154
10717 msgid "B<WUNTRACED>"
10720 #. type: Plain text
10721 #: build/C/man2/wait.2:163
10723 "also return if a child has stopped (but not traced via B<ptrace>(2)). "
10724 "Status for I<traced> children which have stopped is provided even if this "
10725 "option is not specified."
10729 #: build/C/man2/wait.2:163
10731 msgid "B<WCONTINUED> (since Linux 2.6.10)"
10734 #. type: Plain text
10735 #: build/C/man2/wait.2:167
10736 msgid "also return if a stopped child has been resumed by delivery of B<SIGCONT>."
10739 #. type: Plain text
10740 #: build/C/man2/wait.2:169
10741 msgid "(For Linux-only options, see below.)"
10744 #. type: Plain text
10745 #: build/C/man2/wait.2:183
10747 "If I<status> is not NULL, B<wait>() and B<waitpid>() store status "
10748 "information in the I<int> to which it points. This integer can be inspected "
10749 "with the following macros (which take the integer itself as an argument, not "
10750 "a pointer to it, as is done in B<wait>() and B<waitpid>()!):"
10754 #: build/C/man2/wait.2:183
10756 msgid "B<WIFEXITED(>I<status>B<)>"
10759 #. type: Plain text
10760 #: build/C/man2/wait.2:191
10762 "returns true if the child terminated normally, that is, by calling "
10763 "B<exit>(3) or B<_exit>(2), or by returning from main()."
10767 #: build/C/man2/wait.2:191
10769 msgid "B<WEXITSTATUS(>I<status>B<)>"
10772 #. type: Plain text
10773 #: build/C/man2/wait.2:204
10775 "returns the exit status of the child. This consists of the least "
10776 "significant 8 bits of the I<status> argument that the child specified in a "
10777 "call to B<exit>(3) or B<_exit>(2) or as the argument for a return "
10778 "statement in main(). This macro should be employed only if B<WIFEXITED> "
10783 #: build/C/man2/wait.2:204
10785 msgid "B<WIFSIGNALED(>I<status>B<)>"
10788 #. type: Plain text
10789 #: build/C/man2/wait.2:207
10790 msgid "returns true if the child process was terminated by a signal."
10794 #: build/C/man2/wait.2:207
10796 msgid "B<WTERMSIG(>I<status>B<)>"
10799 #. type: Plain text
10800 #: build/C/man2/wait.2:214
10802 "returns the number of the signal that caused the child process to "
10803 "terminate. This macro should be employed only if B<WIFSIGNALED> returned "
10808 #: build/C/man2/wait.2:214
10810 msgid "B<WCOREDUMP(>I<status>B<)>"
10813 #. type: Plain text
10814 #: build/C/man2/wait.2:223
10816 "returns true if the child produced a core dump. This macro should be "
10817 "employed only if B<WIFSIGNALED> returned true. This macro is not specified "
10818 "in POSIX.1-2001 and is not available on some UNIX implementations (e.g., "
10819 "AIX, SunOS). Only use this enclosed in #ifdef WCOREDUMP ... #endif."
10823 #: build/C/man2/wait.2:223
10825 msgid "B<WIFSTOPPED(>I<status>B<)>"
10828 #. type: Plain text
10829 #: build/C/man2/wait.2:230
10831 "returns true if the child process was stopped by delivery of a signal; this "
10832 "is possible only if the call was done using B<WUNTRACED> or when the child "
10833 "is being traced (see B<ptrace>(2))."
10837 #: build/C/man2/wait.2:230
10839 msgid "B<WSTOPSIG(>I<status>B<)>"
10842 #. type: Plain text
10843 #: build/C/man2/wait.2:236
10845 "returns the number of the signal which caused the child to stop. This macro "
10846 "should be employed only if B<WIFSTOPPED> returned true."
10850 #: build/C/man2/wait.2:236
10852 msgid "B<WIFCONTINUED(>I<status>B<)>"
10855 #. type: Plain text
10856 #: build/C/man2/wait.2:241
10858 "(since Linux 2.6.10) returns true if the child process was resumed by "
10859 "delivery of B<SIGCONT>."
10863 #: build/C/man2/wait.2:241
10868 #. type: Plain text
10869 #: build/C/man2/wait.2:246
10871 "The B<waitid>() system call (available since Linux 2.6.9) provides more "
10872 "precise control over which child state changes to wait for."
10875 #. type: Plain text
10876 #: build/C/man2/wait.2:252
10878 "The I<idtype> and I<id> arguments select the child(ren) to wait for, as "
10883 #: build/C/man2/wait.2:252
10885 msgid "I<idtype> == B<P_PID>"
10888 #. type: Plain text
10889 #: build/C/man2/wait.2:255
10890 msgid "Wait for the child whose process ID matches I<id>."
10894 #: build/C/man2/wait.2:255
10896 msgid "I<idtype> == B<P_PGID>"
10899 #. type: Plain text
10900 #: build/C/man2/wait.2:258
10901 msgid "Wait for any child whose process group ID matches I<id>."
10905 #: build/C/man2/wait.2:258
10907 msgid "I<idtype> == B<P_ALL>"
10910 #. type: Plain text
10911 #: build/C/man2/wait.2:262
10912 msgid "Wait for any child; I<id> is ignored."
10915 #. type: Plain text
10916 #: build/C/man2/wait.2:266
10918 "The child state changes to wait for are specified by ORing one or more of "
10919 "the following flags in I<options>:"
10923 #: build/C/man2/wait.2:266
10928 #. type: Plain text
10929 #: build/C/man2/wait.2:269
10930 msgid "Wait for children that have terminated."
10934 #: build/C/man2/wait.2:269
10936 msgid "B<WSTOPPED>"
10939 #. type: Plain text
10940 #: build/C/man2/wait.2:272
10941 msgid "Wait for children that have been stopped by delivery of a signal."
10945 #: build/C/man2/wait.2:272
10947 msgid "B<WCONTINUED>"
10950 #. type: Plain text
10951 #: build/C/man2/wait.2:277
10953 "Wait for (previously stopped) children that have been resumed by delivery of "
10957 #. type: Plain text
10958 #: build/C/man2/wait.2:280
10959 msgid "The following flags may additionally be ORed in I<options>:"
10962 #. type: Plain text
10963 #: build/C/man2/wait.2:284
10964 msgid "As for B<waitpid>()."
10968 #: build/C/man2/wait.2:284
10973 #. type: Plain text
10974 #: build/C/man2/wait.2:288
10976 "Leave the child in a waitable state; a later wait call can be used to again "
10977 "retrieve the child status information."
10980 #. type: Plain text
10981 #: build/C/man2/wait.2:295
10983 "Upon successful return, B<waitid>() fills in the following fields of the "
10984 "I<siginfo_t> structure pointed to by I<infop>:"
10987 #. type: Plain text
10988 #: build/C/man2/wait.2:298
10989 msgid "The process ID of the child."
10992 #. type: Plain text
10993 #: build/C/man2/wait.2:302
10995 "The real user ID of the child. (This field is not set on most other "
10996 "implementations.)"
10999 #. type: Plain text
11000 #: build/C/man2/wait.2:306
11001 msgid "Always set to B<SIGCHLD>."
11005 #: build/C/man2/wait.2:306
11007 msgid "I<si_status>"
11010 #. type: Plain text
11011 #: build/C/man2/wait.2:316
11013 "Either the exit status of the child, as given to B<_exit>(2) (or "
11014 "B<exit>(3)), or the signal that caused the child to terminate, stop, or "
11015 "continue. The I<si_code> field can be used to determine how to interpret "
11019 #. type: Plain text
11020 #: build/C/man2/wait.2:333
11022 "Set to one of: B<CLD_EXITED> (child called B<_exit>(2)); B<CLD_KILLED> "
11023 "(child killed by signal); B<CLD_DUMPED> (child killed by signal, and dumped "
11024 "core); B<CLD_STOPPED> (child stopped by signal); B<CLD_TRAPPED> (traced "
11025 "child has trapped); or B<CLD_CONTINUED> (child continued by B<SIGCONT>)."
11028 #. POSIX.1-2001 leaves this possibility unspecified; most
11029 #. implementations (including Linux) zero out the structure
11030 #. in this case, but at least one implementation (AIX 5.1)
11031 #. does not -- MTK Nov 04
11032 #. type: Plain text
11033 #: build/C/man2/wait.2:355
11035 "If B<WNOHANG> was specified in I<options> and there were no children in a "
11036 "waitable state, then B<waitid>() returns 0 immediately and the state of the "
11037 "I<siginfo_t> structure pointed to by I<infop> is unspecified. To "
11038 "distinguish this case from that where a child was in a waitable state, zero "
11039 "out the I<si_pid> field before the call and check for a nonzero value in "
11040 "this field after the call returns."
11043 #. type: Plain text
11044 #: build/C/man2/wait.2:359
11046 "B<wait>(): on success, returns the process ID of the terminated child; on "
11047 "error, -1 is returned."
11050 #. type: Plain text
11051 #: build/C/man2/wait.2:368
11053 "B<waitpid>(): on success, returns the process ID of the child whose state "
11054 "has changed; if B<WNOHANG> was specified and one or more child(ren) "
11055 "specified by I<pid> exist, but have not yet changed state, then 0 is "
11056 "returned. On error, -1 is returned."
11059 #. FIXME: As reported by Vegard Nossum, if infop is NULL, then waitid()
11060 #. returns the PID of the child. Either this is a bug, or it is intended
11061 #. behavior that needs to be documented. See my Jan 2009 LKML mail
11062 #. "waitid() return value strangeness when infop is NULL".
11063 #. type: Plain text
11064 #: build/C/man2/wait.2:384
11066 "B<waitid>(): returns 0 on success or if B<WNOHANG> was specified and no "
11067 "child(ren) specified by I<id> has yet changed state; on error, -1 is "
11068 "returned. Each of these calls sets I<errno> to an appropriate value in the "
11069 "case of an error."
11073 #: build/C/man2/wait.2:385 build/C/man2/wait.2:390
11078 #. type: Plain text
11079 #: build/C/man2/wait.2:390
11081 "(for B<wait>()) The calling process does not have any unwaited-for "
11085 #. type: Plain text
11086 #: build/C/man2/wait.2:410
11088 "(for B<waitpid>() or B<waitid>()) The process specified by I<pid> "
11089 "(B<waitpid>()) or I<idtype> and I<id> (B<waitid>()) does not exist or is "
11090 "not a child of the calling process. (This can happen for one's own child if "
11091 "the action for B<SIGCHLD> is set to B<SIG_IGN>. See also the I<Linux Notes> "
11092 "section about threads.)"
11095 #. type: Plain text
11096 #: build/C/man2/wait.2:417
11098 "B<WNOHANG> was not set and an unblocked signal or a B<SIGCHLD> was caught; "
11099 "see B<signal>(7)."
11102 #. type: Plain text
11103 #: build/C/man2/wait.2:422
11104 msgid "The I<options> argument was invalid."
11107 #. type: Plain text
11108 #: build/C/man2/wait.2:437
11110 "A child that terminates, but has not been waited for becomes a \"zombie\". "
11111 "The kernel maintains a minimal set of information about the zombie process "
11112 "(PID, termination status, resource usage information) in order to allow the "
11113 "parent to later perform a wait to obtain information about the child. As "
11114 "long as a zombie is not removed from the system via a wait, it will consume "
11115 "a slot in the kernel process table, and if this table fills, it will not be "
11116 "possible to create further processes. If a parent process terminates, then "
11117 "its \"zombie\" children (if any) are adopted by B<init>(8), which "
11118 "automatically performs a wait to remove the zombies."
11121 #. type: Plain text
11122 #: build/C/man2/wait.2:466
11124 "POSIX.1-2001 specifies that if the disposition of B<SIGCHLD> is set to "
11125 "B<SIG_IGN> or the B<SA_NOCLDWAIT> flag is set for B<SIGCHLD> (see "
11126 "B<sigaction>(2)), then children that terminate do not become zombies and a "
11127 "call to B<wait>() or B<waitpid>() will block until all children have "
11128 "terminated, and then fail with I<errno> set to B<ECHILD>. (The original "
11129 "POSIX standard left the behavior of setting B<SIGCHLD> to B<SIG_IGN> "
11130 "unspecified. Note that even though the default disposition of B<SIGCHLD> is "
11131 "\"ignore\", explicitly setting the disposition to B<SIG_IGN> results in "
11132 "different treatment of zombie process children.)"
11135 #. type: Plain text
11136 #: build/C/man2/wait.2:479
11138 "Linux 2.6 conforms to the POSIX requirements. However, Linux 2.4 (and "
11139 "earlier) does not: if a B<wait>() or B<waitpid>() call is made while "
11140 "B<SIGCHLD> is being ignored, the call behaves just as though B<SIGCHLD> were "
11141 "not being ignored, that is, the call blocks until the next child terminates "
11142 "and then returns the process ID and status of that child."
11145 #. type: Plain text
11146 #: build/C/man2/wait.2:495
11148 "In the Linux kernel, a kernel-scheduled thread is not a distinct construct "
11149 "from a process. Instead, a thread is simply a process that is created using "
11150 "the Linux-unique B<clone>(2) system call; other routines such as the "
11151 "portable B<pthread_create>(3) call are implemented using B<clone>(2). "
11152 "Before Linux 2.4, a thread was just a special case of a process, and as a "
11153 "consequence one thread could not wait on the children of another thread, "
11154 "even when the latter belongs to the same thread group. However, POSIX "
11155 "prescribes such functionality, and since Linux 2.4 a thread can, and by "
11156 "default will, wait on children of other threads in the same thread group."
11159 #. type: Plain text
11160 #: build/C/man2/wait.2:502
11162 "The following Linux-specific I<options> are for use with children created "
11163 "using B<clone>(2); they cannot be used with B<waitid>():"
11167 #: build/C/man2/wait.2:502
11169 msgid "B<__WCLONE>"
11173 #. type: Plain text
11174 #: build/C/man2/wait.2:513
11176 "Wait for \"clone\" children only. If omitted, then wait for \"non-clone\" "
11177 "children only. (A \"clone\" child is one which delivers no signal, or a "
11178 "signal other than B<SIGCHLD> to its parent upon termination.) This option "
11179 "is ignored if B<__WALL> is also specified."
11183 #: build/C/man2/wait.2:513
11185 msgid "B<__WALL> (since Linux 2.4)"
11188 #. since patch-2.3.48
11189 #. type: Plain text
11190 #: build/C/man2/wait.2:518
11191 msgid "Wait for all children, regardless of type (\"clone\" or \"non-clone\")."
11195 #: build/C/man2/wait.2:518
11197 msgid "B<__WNOTHREAD> (since Linux 2.4)"
11200 #. since patch-2.4.0-test8
11201 #. type: Plain text
11202 #: build/C/man2/wait.2:524
11204 "Do not wait for children of other threads in the same thread group. This "
11205 "was the default before Linux 2.4."
11208 #. type: Plain text
11209 #: build/C/man2/wait.2:536
11211 "The raw B<waitid>() system call takes a fith argument, of type I<struct "
11212 "rusage\\ *>. If this argument is non-NULL, then it is used to return "
11213 "resource usage information about the child, in the same manner as "
11214 "B<wait4>(2). See B<getrusage>(2) for details."
11217 #. type: Plain text
11218 #: build/C/man2/wait.2:551
11220 "According to POSIX.1-2008, an application calling B<waitid>() must ensure "
11221 "that I<infop> points to a I<siginfo_t> structure (i.e., that it is a "
11222 "non-null pointer). On Linux, if I<infop> is NULL, B<waitid>() succeeds, "
11223 "and returns the process ID of the waited-for child. Applications should "
11224 "avoid relying on this inconsistent, nonstandard, and unnecessary feature."
11227 #. fork.2 refers to this example program.
11228 #. type: Plain text
11229 #: build/C/man2/wait.2:568
11231 "The following program demonstrates the use of B<fork>(2) and B<waitpid>(). "
11232 "The program creates a child process. If no command-line argument is "
11233 "supplied to the program, then the child suspends its execution using "
11234 "B<pause>(2), to allow the user to send signals to the child. Otherwise, if "
11235 "a command-line argument is supplied, then the child exits immediately, using "
11236 "the integer supplied on the command line as the exit status. The parent "
11237 "process executes a loop that monitors the child using B<waitpid>(), and uses "
11238 "the W*() macros described above to analyze the wait status value."
11241 #. type: Plain text
11242 #: build/C/man2/wait.2:584
11246 "Child PID is 32360\n"
11248 "$B< kill -STOP 32360>\n"
11249 "stopped by signal 19\n"
11250 "$B< kill -CONT 32360>\n"
11252 "$B< kill -TERM 32360>\n"
11253 "killed by signal 15\n"
11254 "[1]+ Done ./a.out\n"
11258 #. type: Plain text
11259 #: build/C/man2/wait.2:593
11262 "#include E<lt>sys/wait.hE<gt>\n"
11263 "#include E<lt>stdlib.hE<gt>\n"
11264 "#include E<lt>unistd.hE<gt>\n"
11265 "#include E<lt>stdio.hE<gt>\n"
11268 #. type: Plain text
11269 #: build/C/man2/wait.2:599
11273 "main(int argc, char *argv[])\n"
11275 " pid_t cpid, w;\n"
11279 #. type: Plain text
11280 #: build/C/man2/wait.2:605
11283 " cpid = fork();\n"
11284 " if (cpid == -1) {\n"
11285 " perror(\"fork\");\n"
11286 " exit(EXIT_FAILURE);\n"
11290 #. type: Plain text
11291 #: build/C/man2/wait.2:611
11294 " if (cpid == 0) { /* Code executed by child */\n"
11295 " printf(\"Child PID is %ld\\en\", (long) getpid());\n"
11296 " if (argc == 1)\n"
11297 " pause(); /* Wait for signals */\n"
11298 " _exit(atoi(argv[1]));\n"
11301 #. type: Plain text
11302 #: build/C/man2/wait.2:619
11305 " } else { /* Code executed by parent */\n"
11307 " w = waitpid(cpid, &status, WUNTRACED | WCONTINUED);\n"
11308 " if (w == -1) {\n"
11309 " perror(\"waitpid\");\n"
11310 " exit(EXIT_FAILURE);\n"
11314 #. type: Plain text
11315 #: build/C/man2/wait.2:633
11318 " if (WIFEXITED(status)) {\n"
11319 " printf(\"exited, status=%d\\en\", WEXITSTATUS(status));\n"
11320 " } else if (WIFSIGNALED(status)) {\n"
11321 " printf(\"killed by signal %d\\en\", WTERMSIG(status));\n"
11322 " } else if (WIFSTOPPED(status)) {\n"
11323 " printf(\"stopped by signal %d\\en\", WSTOPSIG(status));\n"
11324 " } else if (WIFCONTINUED(status)) {\n"
11325 " printf(\"continued\\en\");\n"
11327 " } while (!WIFEXITED(status) && !WIFSIGNALED(status));\n"
11328 " exit(EXIT_SUCCESS);\n"
11333 #. type: Plain text
11334 #: build/C/man2/wait.2:646
11336 "B<_exit>(2), B<clone>(2), B<fork>(2), B<kill>(2), B<ptrace>(2), "
11337 "B<sigaction>(2), B<signal>(2), B<wait4>(2), B<pthread_create>(3), "
11338 "B<credentials>(7), B<signal>(7)"
11342 #: build/C/man2/wait4.2:33
11348 #: build/C/man2/wait4.2:33
11353 #. type: Plain text
11354 #: build/C/man2/wait4.2:36
11355 msgid "wait3, wait4 - wait for process to change state, BSD style"
11358 #. type: Plain text
11359 #: build/C/man2/wait4.2:42
11362 "B<#include E<lt>sys/types.hE<gt>>\n"
11363 "B<#include E<lt>sys/time.hE<gt>>\n"
11364 "B<#include E<lt>sys/resource.hE<gt>>\n"
11365 "B<#include E<lt>sys/wait.hE<gt>>\n"
11368 #. type: Plain text
11369 #: build/C/man2/wait4.2:45
11372 "B<pid_t wait3(int *>I<status>B<, int >I<options>B<,>\n"
11373 "B< struct rusage *>I<rusage>B<);>\n"
11376 #. type: Plain text
11377 #: build/C/man2/wait4.2:48
11380 "B<pid_t wait4(pid_t >I<pid>B<, int *>I<status>B<, int >I<options>B<,>\n"
11381 "B< struct rusage *>I<rusage>B<);>\n"
11384 #. type: Plain text
11385 #: build/C/man2/wait4.2:57
11386 msgid "B<wait3>():"
11389 #. type: Plain text
11390 #: build/C/man2/wait4.2:63
11391 msgid "B<wait4>():"
11394 #. type: Plain text
11395 #: build/C/man2/wait4.2:65
11396 msgid "_BSD_SOURCE"
11399 #. type: Plain text
11400 #: build/C/man2/wait4.2:73
11402 "These functions are obsolete; use B<waitpid>(2) or B<waitid>(2) in new "
11406 #. type: Plain text
11407 #: build/C/man2/wait4.2:83
11409 "The B<wait3>() and B<wait4>() system calls are similar to B<waitpid>(2), "
11410 "but additionally return resource usage information about the child in the "
11411 "structure pointed to by I<rusage>."
11414 #. type: Plain text
11415 #: build/C/man2/wait4.2:89
11417 "Other than the use of the I<rusage> argument, the following B<wait3>() "
11421 #. type: Plain text
11422 #: build/C/man2/wait4.2:92
11424 msgid " wait3(status, options, rusage);\n"
11427 #. type: Plain text
11428 #: build/C/man2/wait4.2:95 build/C/man2/wait4.2:109
11429 msgid "is equivalent to:"
11432 #. type: Plain text
11433 #: build/C/man2/wait4.2:98
11435 msgid " waitpid(-1, status, options);\n"
11438 #. type: Plain text
11439 #: build/C/man2/wait4.2:103
11440 msgid "Similarly, the following B<wait4>() call:"
11443 #. type: Plain text
11444 #: build/C/man2/wait4.2:106
11446 msgid " wait4(pid, status, options, rusage);\n"
11449 #. type: Plain text
11450 #: build/C/man2/wait4.2:112
11452 msgid " waitpid(pid, status, options);\n"
11455 #. type: Plain text
11456 #: build/C/man2/wait4.2:122
11458 "In other words, B<wait3>() waits of any child, while B<wait4>() can be "
11459 "used to select a specific child, or children, on which to wait. See "
11460 "B<wait>(2) for further details."
11463 #. type: Plain text
11464 #: build/C/man2/wait4.2:132
11466 "If I<rusage> is not NULL, the I<struct rusage> to which it points will be "
11467 "filled with accounting information about the child. See B<getrusage>(2) "
11471 #. type: Plain text
11472 #: build/C/man2/wait4.2:135 build/C/man2/wait4.2:138
11473 msgid "As for B<waitpid>(2)."
11476 #. type: Plain text
11477 #: build/C/man2/wait4.2:140
11481 #. type: Plain text
11482 #: build/C/man2/wait4.2:147
11484 "SUSv1 included a specification of B<wait3>(); SUSv2 included B<wait3>(), but "
11485 "marked it LEGACY; SUSv3 removed it."
11488 #. type: Plain text
11489 #: build/C/man2/wait4.2:159
11491 "Including I<E<lt>sys/time.hE<gt>> is not required these days, but increases "
11492 "portability. (Indeed, I<E<lt>sys/resource.hE<gt>> defines the I<rusage> "
11493 "structure with fields of type I<struct timeval> defined in "
11494 "I<E<lt>sys/time.hE<gt>>.)"
11497 #. type: Plain text
11498 #: build/C/man2/wait4.2:165
11500 "On Linux, B<wait3>() is a library function implemented on top of the "
11501 "B<wait4>() system call."
11504 #. type: Plain text
11505 #: build/C/man2/wait4.2:172
11507 "B<fork>(2), B<getrusage>(2), B<sigaction>(2), B<signal>(2), B<wait>(2), "