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: 2012-03-22 04:25+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"
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20 #: build/C/man7/epoll.7:21
26 #: build/C/man7/epoll.7:21
32 #: build/C/man7/epoll.7:21 build/C/man2/epoll_create.2:25 build/C/man2/epoll_ctl.2:21 build/C/man2/epoll_wait.2:23 build/C/man2/poll.2:31
38 #: build/C/man7/epoll.7:21 build/C/man2/epoll_create.2:25 build/C/man2/epoll_ctl.2:21 build/C/man2/epoll_wait.2:23 build/C/man2/poll.2:31
40 msgid "Linux Programmer's Manual"
44 #: build/C/man7/epoll.7:22 build/C/man2/epoll_create.2:26 build/C/man2/epoll_ctl.2:22 build/C/man2/epoll_wait.2:24 build/C/man2/poll.2:32
50 #: build/C/man7/epoll.7:24
51 msgid "epoll - I/O event notification facility"
55 #: build/C/man7/epoll.7:24 build/C/man2/epoll_create.2:28 build/C/man2/epoll_ctl.2:24 build/C/man2/epoll_wait.2:26 build/C/man2/poll.2:34
61 #: build/C/man7/epoll.7:26 build/C/man2/epoll_ctl.2:26
62 msgid "B<#include E<lt>sys/epoll.hE<gt>>"
66 #: build/C/man7/epoll.7:26 build/C/man2/epoll_create.2:35 build/C/man2/epoll_ctl.2:29 build/C/man2/epoll_wait.2:36 build/C/man2/poll.2:46
72 #: build/C/man7/epoll.7:36
74 "B<epoll> is a variant of B<poll>(2) that can be used either as an "
75 "edge-triggered or a level-triggered interface and scales well to large "
76 "numbers of watched file descriptors. The following system calls are "
77 "provided to create and manage an B<epoll> instance:"
81 #: build/C/man7/epoll.7:36 build/C/man7/epoll.7:46 build/C/man7/epoll.7:54
87 #: build/C/man7/epoll.7:46
89 "An B<epoll> instance created by B<epoll_create>(2), which returns a file "
90 "descriptor referring to the epoll instance. (The more recent "
91 "B<epoll_create1>(2) extends the functionality of B<epoll_create>(2).)"
95 #: build/C/man7/epoll.7:54
97 "Interest in particular file descriptors is then registered via "
98 "B<epoll_ctl>(2). The set of file descriptors currently registered on an "
99 "B<epoll> instance is sometimes called an I<epoll> set."
103 #: build/C/man7/epoll.7:57
104 msgid "Finally, the actual wait is started by B<epoll_wait>(2)."
108 #: build/C/man7/epoll.7:57
110 msgid "Level-Triggered and Edge-Triggered"
114 #: build/C/man7/epoll.7:66
116 "The B<epoll> event distribution interface is able to behave both as "
117 "edge-triggered (ET) and as level-triggered (LT). The difference between the "
118 "two mechanisms can be described as follows. Suppose that this scenario "
123 #: build/C/man7/epoll.7:66
129 #: build/C/man7/epoll.7:72
131 "The file descriptor that represents the read side of a pipe (I<rfd>) is "
132 "registered on the B<epoll> instance."
136 #: build/C/man7/epoll.7:72
142 #: build/C/man7/epoll.7:74
143 msgid "A pipe writer writes 2 kB of data on the write side of the pipe."
147 #: build/C/man7/epoll.7:74
153 #: build/C/man7/epoll.7:80
155 "A call to B<epoll_wait>(2) is done that will return I<rfd> as a ready file "
160 #: build/C/man7/epoll.7:80
166 #: build/C/man7/epoll.7:83
167 msgid "The pipe reader reads 1 kB of data from I<rfd>."
171 #: build/C/man7/epoll.7:83
177 #: build/C/man7/epoll.7:87
178 msgid "A call to B<epoll_wait>(2) is done."
182 #: build/C/man7/epoll.7:122
184 "If the I<rfd> file descriptor has been added to the B<epoll> interface using "
185 "the B<EPOLLET> (edge-triggered) flag, the call to B<epoll_wait>(2) done in "
186 "step B<5> will probably hang despite the available data still present in the "
187 "file input buffer; meanwhile the remote peer might be expecting a response "
188 "based on the data it already sent. The reason for this is that "
189 "edge-triggered mode only delivers events when changes occur on the monitored "
190 "file descriptor. So, in step B<5> the caller might end up waiting for some "
191 "data that is already present inside the input buffer. In the above example, "
192 "an event on I<rfd> will be generated because of the write done in B<2> and "
193 "the event is consumed in B<3>. Since the read operation done in B<4> does "
194 "not consume the whole buffer data, the call to B<epoll_wait>(2) done in "
195 "step B<5> might block indefinitely."
199 #: build/C/man7/epoll.7:132
201 "An application that employs the B<EPOLLET> flag should use nonblocking file "
202 "descriptors to avoid having a blocking read or write starve a task that is "
203 "handling multiple file descriptors. The suggested way to use B<epoll> as an "
204 "edge-triggered (B<EPOLLET>) interface is as follows:"
208 #: build/C/man7/epoll.7:133
214 #: build/C/man7/epoll.7:136
215 msgid "with nonblocking file descriptors; and"
219 #: build/C/man7/epoll.7:136
225 #: build/C/man7/epoll.7:144
227 "by waiting for an event only after B<read>(2) or B<write>(2) return "
232 #: build/C/man7/epoll.7:155
234 "By contrast, when used as a level-triggered interface (the default, when "
235 "B<EPOLLET> is not specified), B<epoll> is simply a faster B<poll>(2), and "
236 "can be used wherever the latter is used since it shares the same semantics."
240 #: build/C/man7/epoll.7:172
242 "Since even with edge-triggered B<epoll>, multiple events can be generated "
243 "upon receipt of multiple chunks of data, the caller has the option to "
244 "specify the B<EPOLLONESHOT> flag, to tell B<epoll> to disable the associated "
245 "file descriptor after the receipt of an event with B<epoll_wait>(2). When "
246 "the B<EPOLLONESHOT> flag is specified, it is the caller's responsibility to "
247 "rearm the file descriptor using B<epoll_ctl>(2) with B<EPOLL_CTL_MOD>."
251 #: build/C/man7/epoll.7:172
253 msgid "/proc interfaces"
256 #. Following was added in 2.6.28, but them removed in 2.6.29
258 #. .IR /proc/sys/fs/epoll/max_user_instances " (since Linux 2.6.28)"
259 #. This specifies an upper limit on the number of epoll instances
260 #. that can be created per real user ID.
262 #: build/C/man7/epoll.7:180
264 "The following interfaces can be used to limit the amount of kernel memory "
269 #: build/C/man7/epoll.7:180
271 msgid "I</proc/sys/fs/epoll/max_user_watches> (since Linux 2.6.28)"
274 #. 2.6.29 (in 2.6.28, the default was 1/32 of lowmem)
276 #: build/C/man7/epoll.7:194
278 "This specifies a limit on the total number of file descriptors that a user "
279 "can register across all epoll instances on the system. The limit is per "
280 "real user ID. Each registered file descriptor costs roughly 90 bytes on a "
281 "32-bit kernel, and roughly 160 bytes on a 64-bit kernel. Currently, the "
282 "default value for I<max_user_watches> is 1/25 (4%) of the available low "
283 "memory, divided by the registration cost in bytes."
287 #: build/C/man7/epoll.7:194
289 msgid "Example for Suggested Usage"
293 #: build/C/man7/epoll.7:223
295 "While the usage of B<epoll> when employed as a level-triggered interface "
296 "does have the same semantics as B<poll>(2), the edge-triggered usage "
297 "requires more clarification to avoid stalls in the application event loop. "
298 "In this example, listener is a nonblocking socket on which B<listen>(2) has "
299 "been called. The function I<do_use_fd()> uses the new ready file descriptor "
300 "until B<EAGAIN> is returned by either B<read>(2) or B<write>(2). An "
301 "event-driven state machine application should, after having received "
302 "B<EAGAIN>, record its current state so that at the next call to "
303 "I<do_use_fd()> it will continue to B<read>(2) or B<write>(2) from where it "
308 #: build/C/man7/epoll.7:229
311 "#define MAX_EVENTS 10\n"
312 "struct epoll_event ev, events[MAX_EVENTS];\n"
313 "int listen_sock, conn_sock, nfds, epollfd;\n"
317 #: build/C/man7/epoll.7:232
320 "/* Set up listening socket, \\(aqlisten_sock\\(aq (socket(),\n"
321 " bind(), listen()) */\n"
325 #: build/C/man7/epoll.7:238
328 "epollfd = epoll_create(10);\n"
329 "if (epollfd == -1) {\n"
330 " perror(\"epoll_create\");\n"
331 " exit(EXIT_FAILURE);\n"
336 #: build/C/man7/epoll.7:245
339 "ev.events = EPOLLIN;\n"
340 "ev.data.fd = listen_sock;\n"
341 "if (epoll_ctl(epollfd, EPOLL_CTL_ADD, listen_sock, &ev) == -1) {\n"
342 " perror(\"epoll_ctl: listen_sock\");\n"
343 " exit(EXIT_FAILURE);\n"
348 #: build/C/man7/epoll.7:252
352 " nfds = epoll_wait(epollfd, events, MAX_EVENTS, -1);\n"
353 " if (nfds == -1) {\n"
354 " perror(\"epoll_pwait\");\n"
355 " exit(EXIT_FAILURE);\n"
360 #: build/C/man7/epoll.7:274
363 " for (n = 0; n E<lt> nfds; ++n) {\n"
364 " if (events[n].data.fd == listen_sock) {\n"
365 " conn_sock = accept(listen_sock,\n"
366 " (struct sockaddr *) &local, &addrlen);\n"
367 " if (conn_sock == -1) {\n"
368 " perror(\"accept\");\n"
369 " exit(EXIT_FAILURE);\n"
371 " setnonblocking(conn_sock);\n"
372 " ev.events = EPOLLIN | EPOLLET;\n"
373 " ev.data.fd = conn_sock;\n"
374 " if (epoll_ctl(epollfd, EPOLL_CTL_ADD, conn_sock,\n"
376 " perror(\"epoll_ctl: conn_sock\");\n"
377 " exit(EXIT_FAILURE);\n"
380 " do_use_fd(events[n].data.fd);\n"
387 #: build/C/man7/epoll.7:293
389 "When used as an edge-triggered interface, for performance reasons, it is "
390 "possible to add the file descriptor inside the B<epoll> interface "
391 "(B<EPOLL_CTL_ADD>) once by specifying (B<EPOLLIN>|B<EPOLLOUT>). This "
392 "allows you to avoid continuously switching between B<EPOLLIN> and "
393 "B<EPOLLOUT> calling B<epoll_ctl>(2) with B<EPOLL_CTL_MOD>."
397 #: build/C/man7/epoll.7:293
399 msgid "Questions and Answers"
403 #: build/C/man7/epoll.7:294
409 #: build/C/man7/epoll.7:299
411 "What is the key used to distinguish the file descriptors registered in an "
416 #: build/C/man7/epoll.7:299
422 #: build/C/man7/epoll.7:305
424 "The key is the combination of the file descriptor number and the open file "
425 "description (also known as an \"open file handle\", the kernel's internal "
426 "representation of an open file)."
430 #: build/C/man7/epoll.7:305
436 #: build/C/man7/epoll.7:310
438 "What happens if you register the same file descriptor on an B<epoll> "
443 #: build/C/man7/epoll.7:310
448 #. But a descriptor duplicated by fork(2) can't be added to the
449 #. set, because the [file *, fd] pair is already in the epoll set.
450 #. That is a somewhat ugly inconsistency. On the one hand, a child process
451 #. cannot add the duplicate file descriptor to the epoll set. (In every
452 #. other case that I can think of, descriptors duplicated by fork have
453 #. similar semantics to descriptors duplicated by dup() and friends.) On
454 #. the other hand, the very fact that the child has a duplicate of the
455 #. descriptor means that even if the parent closes its descriptor, then
456 #. epoll_wait() in the parent will continue to receive notifications for
457 #. that descriptor because of the duplicated descriptor in the child.
459 #. See http://thread.gmane.org/gmane.linux.kernel/596462/
460 #. "epoll design problems with common fork/exec patterns"
464 #: build/C/man7/epoll.7:341
466 "You will probably get B<EEXIST>. However, it is possible to add a duplicate "
467 "(B<dup>(2), B<dup2>(2), B<fcntl>(2) B<F_DUPFD>) descriptor to the same "
468 "B<epoll> instance. This can be a useful technique for filtering events, if "
469 "the duplicate file descriptors are registered with different I<events> "
474 #: build/C/man7/epoll.7:341
480 #: build/C/man7/epoll.7:349
482 "Can two B<epoll> instances wait for the same file descriptor? If so, are "
483 "events reported to both B<epoll> file descriptors?"
487 #: build/C/man7/epoll.7:349
493 #: build/C/man7/epoll.7:353
495 "Yes, and events would be reported to both. However, careful programming may "
496 "be needed to do this correctly."
500 #: build/C/man7/epoll.7:353
506 #: build/C/man7/epoll.7:358
507 msgid "Is the B<epoll> file descriptor itself poll/epoll/selectable?"
511 #: build/C/man7/epoll.7:358
517 #: build/C/man7/epoll.7:365
519 "Yes. If an B<epoll> file descriptor has events waiting then it will "
520 "indicate as being readable."
524 #: build/C/man7/epoll.7:365
530 #: build/C/man7/epoll.7:370
532 "What happens if one attempts to put an B<epoll> file descriptor into its own "
533 "file descriptor set?"
537 #: build/C/man7/epoll.7:370
543 #: build/C/man7/epoll.7:381
545 "The B<epoll_ctl>(2) call will fail (B<EINVAL>). However, you can add an "
546 "B<epoll> file descriptor inside another B<epoll> file descriptor set."
550 #: build/C/man7/epoll.7:381
556 #: build/C/man7/epoll.7:386
558 "Can I send an B<epoll> file descriptor over a UNIX domain socket to another "
563 #: build/C/man7/epoll.7:386
569 #: build/C/man7/epoll.7:392
571 "Yes, but it does not make sense to do this, since the receiving process "
572 "would not have copies of the file descriptors in the B<epoll> set."
576 #: build/C/man7/epoll.7:392
582 #: build/C/man7/epoll.7:397
584 "Will closing a file descriptor cause it to be removed from all B<epoll> sets "
589 #: build/C/man7/epoll.7:397
595 #: build/C/man7/epoll.7:425
597 "Yes, but be aware of the following point. A file descriptor is a reference "
598 "to an open file description (see B<open>(2)). Whenever a descriptor is "
599 "duplicated via B<dup>(2), B<dup2>(2), B<fcntl>(2) B<F_DUPFD>, or "
600 "B<fork>(2), a new file descriptor referring to the same open file "
601 "description is created. An open file description continues to exist until "
602 "all file descriptors referring to it have been closed. A file descriptor is "
603 "removed from an B<epoll> set only after all the file descriptors referring "
604 "to the underlying open file description have been closed (or before if the "
605 "descriptor is explicitly removed using B<epoll_ctl>(2) B<EPOLL_CTL_DEL>). "
606 "This means that even after a file descriptor that is part of an B<epoll> set "
607 "has been closed, events may be reported for that file descriptor if other "
608 "file descriptors referring to the same underlying file description remain "
613 #: build/C/man7/epoll.7:425
619 #: build/C/man7/epoll.7:430
621 "If more than one event occurs between B<epoll_wait>(2) calls, are they "
622 "combined or reported separately?"
626 #: build/C/man7/epoll.7:430
632 #: build/C/man7/epoll.7:433
633 msgid "They will be combined."
637 #: build/C/man7/epoll.7:433
643 #: build/C/man7/epoll.7:437
645 "Does an operation on a file descriptor affect the already collected but not "
646 "yet reported events?"
650 #: build/C/man7/epoll.7:437
656 #: build/C/man7/epoll.7:443
658 "You can do two operations on an existing file descriptor. Remove would be "
659 "meaningless for this case. Modify will reread available I/O."
663 #: build/C/man7/epoll.7:443
669 #: build/C/man7/epoll.7:451
671 "Do I need to continuously read/write a file descriptor until B<EAGAIN> when "
672 "using the B<EPOLLET> flag (edge-triggered behavior) ?"
676 #: build/C/man7/epoll.7:451
682 #: build/C/man7/epoll.7:461
684 "Receiving an event from B<epoll_wait>(2) should suggest to you that such "
685 "file descriptor is ready for the requested I/O operation. You must consider "
686 "it ready until the next (nonblocking) read/write yields B<EAGAIN>. When "
687 "and how you will use the file descriptor is entirely up to you."
691 #: build/C/man7/epoll.7:467
693 "For packet/token-oriented files (e.g., datagram socket, terminal in "
694 "canonical mode), the only way to detect the end of the read/write I/O space "
695 "is to continue to read/write until B<EAGAIN>."
699 #: build/C/man7/epoll.7:483
701 "For stream-oriented files (e.g., pipe, FIFO, stream socket), the condition "
702 "that the read/write I/O space is exhausted can also be detected by checking "
703 "the amount of data read from / written to the target file descriptor. For "
704 "example, if you call B<read>(2) by asking to read a certain amount of data "
705 "and B<read>(2) returns a lower number of bytes, you can be sure of having "
706 "exhausted the read I/O space for the file descriptor. The same is true when "
707 "writing using B<write>(2). (Avoid this latter technique if you cannot "
708 "guarantee that the monitored file descriptor always refers to a "
709 "stream-oriented file.)"
713 #: build/C/man7/epoll.7:483
715 msgid "Possible Pitfalls and Ways to Avoid Them"
719 #: build/C/man7/epoll.7:484
721 msgid "B<o Starvation (edge-triggered)>"
725 #: build/C/man7/epoll.7:492
727 "If there is a large amount of I/O space, it is possible that by trying to "
728 "drain it the other files will not get processed causing starvation. (This "
729 "problem is not specific to B<epoll>.)"
733 #: build/C/man7/epoll.7:500
735 "The solution is to maintain a ready list and mark the file descriptor as "
736 "ready in its associated data structure, thereby allowing the application to "
737 "remember which files need to be processed but still round robin amongst all "
738 "the ready files. This also supports ignoring subsequent events you receive "
739 "for file descriptors that are already ready."
743 #: build/C/man7/epoll.7:500
745 msgid "B<o If using an event cache...>"
749 #: build/C/man7/epoll.7:516
751 "If you use an event cache or store all the file descriptors returned from "
752 "B<epoll_wait>(2), then make sure to provide a way to mark its closure "
753 "dynamically (i.e., caused by a previous event's processing). Suppose you "
754 "receive 100 events from B<epoll_wait>(2), and in event #47 a condition "
755 "causes event #13 to be closed. If you remove the structure and B<close>(2) "
756 "the file descriptor for event #13, then your event cache might still say "
757 "there are events waiting for that file descriptor causing confusion."
761 #: build/C/man7/epoll.7:527
763 "One solution for this is to call, during the processing of event 47, "
764 "B<epoll_ctl>(B<EPOLL_CTL_DEL>) to delete file descriptor 13 and "
765 "B<close>(2), then mark its associated data structure as removed and link it "
766 "to a cleanup list. If you find another event for file descriptor 13 in your "
767 "batch processing, you will discover the file descriptor had been previously "
768 "removed and there will be no confusion."
772 #: build/C/man7/epoll.7:527 build/C/man2/epoll_create.2:114 build/C/man2/epoll_ctl.2:224 build/C/man2/epoll_wait.2:174 build/C/man2/poll.2:286
777 #. Its interface should be finalized in Linux kernel 2.5.66.
779 #: build/C/man7/epoll.7:533
781 "The B<epoll> API was introduced in Linux kernel 2.5.44. Support was added "
782 "to glibc in version 2.3.2."
786 #: build/C/man7/epoll.7:533 build/C/man2/epoll_create.2:124 build/C/man2/epoll_ctl.2:229 build/C/man2/epoll_wait.2:184 build/C/man2/poll.2:306
788 msgid "CONFORMING TO"
792 #: build/C/man7/epoll.7:542
794 "The B<epoll> API is Linux-specific. Some other systems provide similar "
795 "mechanisms, for example, FreeBSD has I<kqueue>, and Solaris has "
800 #: build/C/man7/epoll.7:542 build/C/man2/epoll_create.2:133 build/C/man2/epoll_ctl.2:252 build/C/man2/epoll_wait.2:187 build/C/man2/poll.2:338
806 #: build/C/man7/epoll.7:547
807 msgid "B<epoll_create>(2), B<epoll_create1>(2), B<epoll_ctl>(2), B<epoll_wait>(2)"
811 #: build/C/man7/epoll.7:547 build/C/man2/epoll_create.2:138 build/C/man2/epoll_ctl.2:257 build/C/man2/epoll_wait.2:191 build/C/man2/poll.2:342
817 #: build/C/man7/epoll.7:554 build/C/man2/epoll_create.2:145 build/C/man2/epoll_ctl.2:264 build/C/man2/epoll_wait.2:198 build/C/man2/poll.2:349
819 "This page is part of release 3.37 of the Linux I<man-pages> project. A "
820 "description of the project, and information about reporting bugs, can be "
821 "found at http://www.kernel.org/doc/man-pages/."
825 #: build/C/man2/epoll_create.2:25
831 #: build/C/man2/epoll_create.2:25 build/C/man2/epoll_ctl.2:21 build/C/man2/epoll_wait.2:23
837 #: build/C/man2/epoll_create.2:28
838 msgid "epoll_create, epoll_create1 - open an epoll file descriptor"
842 #: build/C/man2/epoll_create.2:31 build/C/man2/epoll_wait.2:29
844 msgid "B<#include E<lt>sys/epoll.hE<gt>>\n"
848 #: build/C/man2/epoll_create.2:34
851 "B<int epoll_create(int >I<size>B<);>\n"
852 "B<int epoll_create1(int >I<flags>B<);>\n"
856 #: build/C/man2/epoll_create.2:48
858 "B<epoll_create>() creates an epoll \"instance\", requesting the kernel to "
859 "allocate an event backing store dimensioned for I<size> descriptors. The "
860 "I<size> is not the maximum size of the backing store but just a hint to the "
861 "kernel about how to dimension internal structures. (Nowadays, I<size> is "
862 "unused; see NOTES below.)"
866 #: build/C/man2/epoll_create.2:61
868 "B<epoll_create>() returns a file descriptor referring to the new epoll "
869 "instance. This file descriptor is used for all the subsequent calls to the "
870 "B<epoll> interface. When no longer required, the file descriptor returned "
871 "by B<epoll_create>() should be closed by using B<close>(2). When all file "
872 "descriptors referring to an epoll instance have been closed, the kernel "
873 "destroys the instance and releases the associated resources for reuse."
877 #: build/C/man2/epoll_create.2:73
879 "If I<flags> is 0, then, other than the fact that the obsolete I<size> "
880 "argument is dropped, B<epoll_create1>() is the same as B<epoll_create>(). "
881 "The following value can be included in I<flags> to obtain different "
886 #: build/C/man2/epoll_create.2:73
888 msgid "B<EPOLL_CLOEXEC>"
892 #: build/C/man2/epoll_create.2:83
894 "Set the close-on-exec (B<FD_CLOEXEC>) flag on the new file descriptor. See "
895 "the description of the B<O_CLOEXEC> flag in B<open>(2) for reasons why this "
900 #: build/C/man2/epoll_create.2:83 build/C/man2/epoll_ctl.2:156 build/C/man2/epoll_wait.2:137 build/C/man2/poll.2:257
906 #: build/C/man2/epoll_create.2:90
908 "On success, these system calls return a nonnegative file descriptor. On "
909 "error, -1 is returned, and I<errno> is set to indicate the error."
913 #: build/C/man2/epoll_create.2:90 build/C/man2/epoll_ctl.2:165 build/C/man2/epoll_wait.2:149 build/C/man2/poll.2:267
919 #: build/C/man2/epoll_create.2:91 build/C/man2/epoll_create.2:95 build/C/man2/epoll_ctl.2:180 build/C/man2/epoll_wait.2:166 build/C/man2/poll.2:276
925 #: build/C/man2/epoll_create.2:95
926 msgid "I<size> is not positive."
930 #: build/C/man2/epoll_create.2:100
931 msgid "(B<epoll_create1>()) Invalid value specified in I<flags>."
935 #: build/C/man2/epoll_create.2:100
941 #: build/C/man2/epoll_create.2:108
943 "The per-user limit on the number of epoll instances imposed by "
944 "I</proc/sys/fs/epoll/max_user_instances> was encountered. See B<epoll>(7) "
945 "for further details."
949 #: build/C/man2/epoll_create.2:108
955 #: build/C/man2/epoll_create.2:111
956 msgid "The system limit on the total number of open files has been reached."
960 #: build/C/man2/epoll_create.2:111 build/C/man2/epoll_ctl.2:203 build/C/man2/poll.2:283
966 #: build/C/man2/epoll_create.2:114
967 msgid "There was insufficient memory to create the kernel object."
971 #: build/C/man2/epoll_create.2:118
973 "B<epoll_create>() was added to the kernel in version 2.6. Library support "
974 "is provided in glibc starting with version 2.3.2."
977 #. To be precise: kernel 2.5.44.
978 #. The interface should be finalized by Linux kernel 2.5.66.
980 #: build/C/man2/epoll_create.2:124
982 "B<epoll_create1>() was added to the kernel in version 2.6.27. Library "
983 "support is provided in glibc starting with version 2.9."
987 #: build/C/man2/epoll_create.2:127
988 msgid "B<epoll_create>() is Linux-specific."
992 #: build/C/man2/epoll_create.2:127 build/C/man2/epoll_ctl.2:233 build/C/man2/poll.2:312
998 #: build/C/man2/epoll_create.2:133
1000 "Since Linux 2.6.8, the I<size> argument is unused, but must be greater than "
1001 "zero. (The kernel dynamically sizes the required data structures without "
1002 "needing this initial hint.)"
1006 #: build/C/man2/epoll_create.2:138
1007 msgid "B<close>(2), B<epoll_ctl>(2), B<epoll_wait>(2), B<epoll>(7)"
1011 #: build/C/man2/epoll_ctl.2:21
1017 #: build/C/man2/epoll_ctl.2:24
1018 msgid "epoll_ctl - control interface for an epoll descriptor"
1022 #: build/C/man2/epoll_ctl.2:29
1024 "B<int epoll_ctl(int >I<epfd>B<, int >I<op>B<, int >I<fd>B<, struct "
1025 "epoll_event *>I<event>B<);>"
1029 #: build/C/man2/epoll_ctl.2:37
1031 "This system call performs control operations on the epoll instance referred "
1032 "to by the file descriptor I<epfd>. It requests that the operation I<op> be "
1033 "performed for the target file descriptor, I<fd>."
1037 #: build/C/man2/epoll_ctl.2:41
1038 msgid "Valid values for the I<op> argument are :"
1042 #: build/C/man2/epoll_ctl.2:41
1044 msgid "B<EPOLL_CTL_ADD>"
1048 #: build/C/man2/epoll_ctl.2:53
1050 "Register the target file descriptor I<fd> on the B<epoll> instance referred "
1051 "to by the file descriptor I<epfd> and associate the event I<event> with the "
1052 "internal file linked to I<fd>."
1056 #: build/C/man2/epoll_ctl.2:53
1058 msgid "B<EPOLL_CTL_MOD>"
1062 #: build/C/man2/epoll_ctl.2:59
1063 msgid "Change the event I<event> associated with the target file descriptor I<fd>."
1067 #: build/C/man2/epoll_ctl.2:59
1069 msgid "B<EPOLL_CTL_DEL>"
1073 #: build/C/man2/epoll_ctl.2:70
1075 "Remove (deregister) the target file descriptor I<fd> from the B<epoll> "
1076 "instance referred to by I<epfd>. The I<event> is ignored and can be NULL "
1077 "(but see BUGS below)."
1081 #: build/C/man2/epoll_ctl.2:78
1083 "The I<event> argument describes the object linked to the file descriptor "
1084 "I<fd>. The I<struct epoll_event> is defined as :"
1088 #: build/C/man2/epoll_ctl.2:87
1091 "typedef union epoll_data {\n"
1100 #: build/C/man2/epoll_ctl.2:92
1103 "struct epoll_event {\n"
1104 " uint32_t events; /* Epoll events */\n"
1105 " epoll_data_t data; /* User data variable */\n"
1110 #: build/C/man2/epoll_ctl.2:99
1112 "The I<events> member is a bit set composed using the following available "
1117 #: build/C/man2/epoll_ctl.2:99
1123 #: build/C/man2/epoll_ctl.2:104
1124 msgid "The associated file is available for B<read>(2) operations."
1128 #: build/C/man2/epoll_ctl.2:104
1134 #: build/C/man2/epoll_ctl.2:109
1135 msgid "The associated file is available for B<write>(2) operations."
1139 #: build/C/man2/epoll_ctl.2:109
1141 msgid "B<EPOLLRDHUP> (since Linux 2.6.17)"
1145 #: build/C/man2/epoll_ctl.2:115
1147 "Stream socket peer closed connection, or shut down writing half of "
1148 "connection. (This flag is especially useful for writing simple code to "
1149 "detect peer shutdown when using Edge Triggered monitoring.)"
1153 #: build/C/man2/epoll_ctl.2:115
1159 #: build/C/man2/epoll_ctl.2:120
1160 msgid "There is urgent data available for B<read>(2) operations."
1164 #: build/C/man2/epoll_ctl.2:120
1170 #: build/C/man2/epoll_ctl.2:126
1172 "Error condition happened on the associated file descriptor. "
1173 "B<epoll_wait>(2) will always wait for this event; it is not necessary to "
1174 "set it in I<events>."
1178 #: build/C/man2/epoll_ctl.2:126
1184 #: build/C/man2/epoll_ctl.2:132
1186 "Hang up happened on the associated file descriptor. B<epoll_wait>(2) will "
1187 "always wait for this event; it is not necessary to set it in I<events>."
1191 #: build/C/man2/epoll_ctl.2:132
1197 #: build/C/man2/epoll_ctl.2:142
1199 "Sets the Edge Triggered behavior for the associated file descriptor. The "
1200 "default behavior for B<epoll> is Level Triggered. See B<epoll>(7) for more "
1201 "detailed information about Edge and Level Triggered event distribution "
1206 #: build/C/man2/epoll_ctl.2:142
1208 msgid "B<EPOLLONESHOT> (since Linux 2.6.2)"
1212 #: build/C/man2/epoll_ctl.2:156
1214 "Sets the one-shot behavior for the associated file descriptor. This means "
1215 "that after an event is pulled out with B<epoll_wait>(2) the associated file "
1216 "descriptor is internally disabled and no other events will be reported by "
1217 "the B<epoll> interface. The user must call B<epoll_ctl>() with "
1218 "B<EPOLL_CTL_MOD> to rearm the file descriptor with a new event mask."
1222 #: build/C/man2/epoll_ctl.2:165
1224 "When successful, B<epoll_ctl>() returns zero. When an error occurs, "
1225 "B<epoll_ctl>() returns -1 and I<errno> is set appropriately."
1229 #: build/C/man2/epoll_ctl.2:166 build/C/man2/epoll_wait.2:150
1235 #: build/C/man2/epoll_ctl.2:172
1236 msgid "I<epfd> or I<fd> is not a valid file descriptor."
1240 #: build/C/man2/epoll_ctl.2:172
1246 #: build/C/man2/epoll_ctl.2:180
1248 "I<op> was B<EPOLL_CTL_ADD>, and the supplied file descriptor I<fd> is "
1249 "already registered with this epoll instance."
1253 #: build/C/man2/epoll_ctl.2:193
1255 "I<epfd> is not an B<epoll> file descriptor, or I<fd> is the same as I<epfd>, "
1256 "or the requested operation I<op> is not supported by this interface."
1260 #: build/C/man2/epoll_ctl.2:193
1266 #: build/C/man2/epoll_ctl.2:203
1268 "I<op> was B<EPOLL_CTL_MOD> or B<EPOLL_CTL_DEL>, and I<fd> is not registered "
1269 "with this epoll instance."
1273 #: build/C/man2/epoll_ctl.2:208
1275 "There was insufficient memory to handle the requested I<op> control "
1280 #: build/C/man2/epoll_ctl.2:208
1286 #: build/C/man2/epoll_ctl.2:218
1288 "The limit imposed by I</proc/sys/fs/epoll/max_user_watches> was encountered "
1289 "while trying to register (B<EPOLL_CTL_ADD>) a new file descriptor on an "
1290 "epoll instance. See B<epoll>(7) for further details."
1294 #: build/C/man2/epoll_ctl.2:218
1300 #: build/C/man2/epoll_ctl.2:224
1301 msgid "The target file I<fd> does not support B<epoll>."
1304 #. To be precise: kernel 2.5.44.
1305 #. The interface should be finalized by Linux kernel 2.5.66.
1307 #: build/C/man2/epoll_ctl.2:229
1308 msgid "B<epoll_ctl>() was added to the kernel in version 2.6."
1312 #: build/C/man2/epoll_ctl.2:233
1314 "B<epoll_ctl>() is Linux-specific. Library support is provided in glibc "
1315 "starting with version 2.3.2."
1319 #: build/C/man2/epoll_ctl.2:238
1321 "The B<epoll> interface supports all file descriptors that support "
1326 #: build/C/man2/epoll_ctl.2:238 build/C/man2/poll.2:334
1332 #: build/C/man2/epoll_ctl.2:252
1334 "In kernel versions before 2.6.9, the B<EPOLL_CTL_DEL> operation required a "
1335 "non-NULL pointer in I<event>, even though this argument is ignored. Since "
1336 "Linux 2.6.9, I<event> can be specified as NULL when using B<EPOLL_CTL_DEL>. "
1337 "Applications that need to be portable to kernels before 2.6.9 should specify "
1338 "a non-NULL pointer in I<event>."
1342 #: build/C/man2/epoll_ctl.2:257
1343 msgid "B<epoll_create>(2), B<epoll_wait>(2), B<poll>(2), B<epoll>(7)"
1347 #: build/C/man2/epoll_wait.2:23
1353 #: build/C/man2/epoll_wait.2:26
1354 msgid "epoll_wait, epoll_pwait - wait for an I/O event on an epoll file descriptor"
1358 #: build/C/man2/epoll_wait.2:35
1361 "B<int epoll_wait(int >I<epfd>B<, struct epoll_event *>I<events>B<,>\n"
1362 "B< int >I<maxevents>B<, int >I<timeout>B<);>\n"
1363 "B<int epoll_pwait(int >I<epfd>B<, struct epoll_event *>I<events>B<,>\n"
1364 "B< int >I<maxevents>B<, int >I<timeout>B<,>\n"
1365 "B< const sigset_t *>I<sigmask>B<);>\n"
1369 #: build/C/man2/epoll_wait.2:53
1371 "The B<epoll_wait>() system call waits for events on the B<epoll> instance "
1372 "referred to by the file descriptor I<epfd>. The memory area pointed to by "
1373 "I<events> will contain the events that will be available for the caller. Up "
1374 "to I<maxevents> are returned by B<epoll_wait>(). The I<maxevents> argument "
1375 "must be greater than zero."
1379 #: build/C/man2/epoll_wait.2:67
1381 "The call waits for a maximum time of I<timeout> milliseconds. Specifying a "
1382 "I<timeout> of -1 makes B<epoll_wait>() wait indefinitely, while specifying "
1383 "a I<timeout> equal to zero makes B<epoll_wait>() to return immediately even "
1384 "if no events are available (return code equal to zero)."
1388 #: build/C/man2/epoll_wait.2:71
1389 msgid "The I<struct epoll_event> is defined as :"
1393 #: build/C/man2/epoll_wait.2:80
1396 "typedef union epoll_data {\n"
1405 #: build/C/man2/epoll_wait.2:85
1408 "struct epoll_event {\n"
1409 " uint32_t events; /* Epoll events */\n"
1410 " epoll_data_t data; /* User data variable */\n"
1415 #: build/C/man2/epoll_wait.2:96
1417 "The I<data> of each returned structure will contain the same data the user "
1418 "set with an B<epoll_ctl>(2) (B<EPOLL_CTL_ADD>,B<EPOLL_CTL_MOD>) while the "
1419 "I<events> member will contain the returned event bit field."
1423 #: build/C/man2/epoll_wait.2:96
1425 msgid "epoll_pwait()"
1429 #: build/C/man2/epoll_wait.2:110
1431 "The relationship between B<epoll_wait>() and B<epoll_pwait>() is analogous "
1432 "to the relationship between B<select>(2) and B<pselect>(2): like "
1433 "B<pselect>(2), B<epoll_pwait>() allows an application to safely wait until "
1434 "either a file descriptor becomes ready or until a signal is caught."
1438 #: build/C/man2/epoll_wait.2:114
1439 msgid "The following B<epoll_pwait>() call:"
1443 #: build/C/man2/epoll_wait.2:117
1445 msgid " ready = epoll_pwait(epfd, &events, maxevents, timeout, &sigmask);\n"
1449 #: build/C/man2/epoll_wait.2:122 build/C/man2/poll.2:206
1450 msgid "is equivalent to I<atomically> executing the following calls:"
1454 #: build/C/man2/epoll_wait.2:125
1456 msgid " sigset_t origmask;\n"
1460 #: build/C/man2/epoll_wait.2:129
1463 " sigprocmask(SIG_SETMASK, &sigmask, &origmask);\n"
1464 " ready = epoll_wait(epfd, &events, maxevents, timeout);\n"
1465 " sigprocmask(SIG_SETMASK, &origmask, NULL);\n"
1469 #: build/C/man2/epoll_wait.2:137
1471 "The I<sigmask> argument may be specified as NULL, in which case "
1472 "B<epoll_pwait>() is equivalent to B<epoll_wait>()."
1476 #: build/C/man2/epoll_wait.2:149
1478 "When successful, B<epoll_wait>() returns the number of file descriptors "
1479 "ready for the requested I/O, or zero if no file descriptor became ready "
1480 "during the requested I<timeout> milliseconds. When an error occurs, "
1481 "B<epoll_wait>() returns -1 and I<errno> is set appropriately."
1485 #: build/C/man2/epoll_wait.2:154
1486 msgid "I<epfd> is not a valid file descriptor."
1490 #: build/C/man2/epoll_wait.2:154 build/C/man2/poll.2:268
1496 #: build/C/man2/epoll_wait.2:159
1498 "The memory area pointed to by I<events> is not accessible with write "
1503 #: build/C/man2/epoll_wait.2:159 build/C/man2/poll.2:272
1509 #: build/C/man2/epoll_wait.2:166
1511 "The call was interrupted by a signal handler before any of the requested "
1512 "events occurred or the I<timeout> expired; see B<signal>(7)."
1516 #: build/C/man2/epoll_wait.2:174
1518 "I<epfd> is not an B<epoll> file descriptor, or I<maxevents> is less than or "
1522 #. To be precise: kernel 2.5.44.
1523 #. The interface should be finalized by Linux kernel 2.5.66.
1525 #: build/C/man2/epoll_wait.2:180
1527 "B<epoll_wait>() was added to the kernel in version 2.6. Library support is "
1528 "provided in glibc starting with version 2.3.2."
1532 #: build/C/man2/epoll_wait.2:184
1534 "B<epoll_pwait>() was added to Linux in kernel 2.6.19. Library support is "
1535 "provided in glibc starting with version 2.6."
1539 #: build/C/man2/epoll_wait.2:187
1540 msgid "B<epoll_wait>() is Linux-specific."
1544 #: build/C/man2/epoll_wait.2:191
1545 msgid "B<epoll_create>(2), B<epoll_ctl>(2), B<epoll>(7)"
1549 #: build/C/man2/poll.2:31
1555 #: build/C/man2/poll.2:31
1561 #: build/C/man2/poll.2:34
1562 msgid "poll, ppoll - wait for some event on a file descriptor"
1566 #: build/C/man2/poll.2:37
1568 msgid "B<#include E<lt>poll.hE<gt>>\n"
1572 #: build/C/man2/poll.2:39
1575 "B<int poll(struct pollfd *>I<fds>B<, nfds_t >I<nfds>B<, int "
1576 ">I<timeout>B<);>\n"
1580 #: build/C/man2/poll.2:42
1583 "B<#define _GNU_SOURCE> /* See feature_test_macros(7) */\n"
1584 "B<#include E<lt>poll.hE<gt>>\n"
1588 #: build/C/man2/poll.2:45
1591 "B<int ppoll(struct pollfd *>I<fds>B<, nfds_t >I<nfds>B<, >\n"
1592 "B< const struct timespec *>I<timeout_ts>B<, const sigset_t "
1593 "*>I<sigmask>B<);>\n"
1597 #: build/C/man2/poll.2:52
1599 "B<poll>() performs a similar task to B<select>(2): it waits for one of a "
1600 "set of file descriptors to become ready to perform I/O."
1604 #: build/C/man2/poll.2:56
1606 "The set of file descriptors to be monitored is specified in the I<fds> "
1607 "argument, which is an array of structures of the following form:"
1611 #: build/C/man2/poll.2:64
1615 " int fd; /* file descriptor */\n"
1616 " short events; /* requested events */\n"
1617 " short revents; /* returned events */\n"
1622 #: build/C/man2/poll.2:71
1624 "The caller should specify the number of items in the I<fds> array in "
1629 #: build/C/man2/poll.2:75
1630 msgid "The field I<fd> contains a file descriptor for an open file."
1634 #: build/C/man2/poll.2:80
1636 "The field I<events> is an input parameter, a bit mask specifying the events "
1637 "the application is interested in."
1641 #: build/C/man2/poll.2:99
1643 "The field I<revents> is an output parameter, filled by the kernel with the "
1644 "events that actually occurred. The bits returned in I<revents> can include "
1645 "any of those specified in I<events>, or one of the values B<POLLERR>, "
1646 "B<POLLHUP>, or B<POLLNVAL>. (These three bits are meaningless in the "
1647 "I<events> field, and will be set in the I<revents> field whenever the "
1648 "corresponding condition is true.)"
1652 #: build/C/man2/poll.2:104
1654 "If none of the events requested (and no error) has occurred for any of the "
1655 "file descriptors, then B<poll>() blocks until one of the events occurs."
1659 #: build/C/man2/poll.2:113
1661 "The I<timeout> argument specifies an upper limit on the time for which "
1662 "B<poll>() will block, in milliseconds. Specifying a negative value in "
1663 "I<timeout> means an infinite timeout."
1667 #: build/C/man2/poll.2:119
1669 "The bits that may be set/returned in I<events> and I<revents> are defined in "
1670 "I<E<lt>poll.hE<gt>>:"
1674 #: build/C/man2/poll.2:120
1680 #: build/C/man2/poll.2:123
1681 msgid "There is data to read."
1685 #: build/C/man2/poll.2:123
1691 #: build/C/man2/poll.2:127
1693 "There is urgent data to read (e.g., out-of-band data on TCP socket; "
1694 "pseudoterminal master in packet mode has seen state change in slave)."
1698 #: build/C/man2/poll.2:127
1704 #: build/C/man2/poll.2:130
1705 msgid "Writing now will not block."
1709 #: build/C/man2/poll.2:130
1711 msgid "B<POLLRDHUP> (since Linux 2.6.17)"
1715 #: build/C/man2/poll.2:141
1717 "Stream socket peer closed connection, or shut down writing half of "
1718 "connection. The B<_GNU_SOURCE> feature test macro must be defined (before "
1719 "including I<any> header files) in order to obtain this definition."
1723 #: build/C/man2/poll.2:141
1729 #: build/C/man2/poll.2:144
1730 msgid "Error condition (output only)."
1734 #: build/C/man2/poll.2:144
1740 #: build/C/man2/poll.2:147
1741 msgid "Hang up (output only)."
1745 #: build/C/man2/poll.2:147
1751 #: build/C/man2/poll.2:152
1752 msgid "Invalid request: I<fd> not open (output only)."
1756 #: build/C/man2/poll.2:158
1758 "When compiling with B<_XOPEN_SOURCE> defined, one also has the following, "
1759 "which convey no further information beyond the bits listed above:"
1763 #: build/C/man2/poll.2:159
1765 msgid "B<POLLRDNORM>"
1769 #: build/C/man2/poll.2:163
1770 msgid "Equivalent to B<POLLIN>."
1774 #: build/C/man2/poll.2:163
1776 msgid "B<POLLRDBAND>"
1779 #. POLLRDBAND is used in the DECnet protocol.
1781 #: build/C/man2/poll.2:167
1782 msgid "Priority band data can be read (generally unused on Linux)."
1786 #: build/C/man2/poll.2:167
1788 msgid "B<POLLWRNORM>"
1792 #: build/C/man2/poll.2:171
1793 msgid "Equivalent to B<POLLOUT>."
1797 #: build/C/man2/poll.2:171
1799 msgid "B<POLLWRBAND>"
1803 #: build/C/man2/poll.2:174
1804 msgid "Priority data may be written."
1808 #: build/C/man2/poll.2:178
1809 msgid "Linux also knows about, but does not use B<POLLMSG>."
1813 #: build/C/man2/poll.2:178
1819 #: build/C/man2/poll.2:192
1821 "The relationship between B<poll>() and B<ppoll>() is analogous to the "
1822 "relationship between B<select>(2) and B<pselect>(2): like B<pselect>(2), "
1823 "B<ppoll>() allows an application to safely wait until either a file "
1824 "descriptor becomes ready or until a signal is caught."
1828 #: build/C/man2/poll.2:198
1830 "Other than the difference in the precision of the I<timeout> argument, the "
1831 "following B<ppoll>() call:"
1835 #: build/C/man2/poll.2:201
1837 msgid " ready = ppoll(&fds, nfds, timeout_ts, &sigmask);\n"
1841 #: build/C/man2/poll.2:210
1844 " sigset_t origmask;\n"
1849 #: build/C/man2/poll.2:216
1852 " timeout = (timeout_ts == NULL) ? -1 :\n"
1853 " (timeout_ts.tv_sec * 1000 + timeout_ts.tv_nsec / 1000000);\n"
1854 " sigprocmask(SIG_SETMASK, &sigmask, &origmask);\n"
1855 " ready = poll(&fds, nfds, timeout);\n"
1856 " sigprocmask(SIG_SETMASK, &origmask, NULL);\n"
1860 #: build/C/man2/poll.2:223
1862 "See the description of B<pselect>(2) for an explanation of why B<ppoll>() "
1867 #: build/C/man2/poll.2:235
1869 "If the I<sigmask> argument is specified as NULL, then no signal mask "
1870 "manipulation is performed (and thus B<ppoll>() differs from B<poll>() only "
1871 "in the precision of the I<timeout> argument)."
1875 #: build/C/man2/poll.2:242
1877 "The I<timeout_ts> argument specifies an upper limit on the amount of time "
1878 "that B<ppoll>() will block. This argument is a pointer to a structure of "
1879 "the following form:"
1883 #: build/C/man2/poll.2:249
1886 "struct timespec {\n"
1887 " long tv_sec; /* seconds */\n"
1888 " long tv_nsec; /* nanoseconds */\n"
1893 #: build/C/man2/poll.2:257
1895 "If I<timeout_ts> is specified as NULL, then B<ppoll>() can block "
1900 #: build/C/man2/poll.2:267
1902 "On success, a positive number is returned; this is the number of structures "
1903 "which have nonzero I<revents> fields (in other words, those descriptors with "
1904 "events or errors reported). A value of 0 indicates that the call timed out "
1905 "and no file descriptors were ready. On error, -1 is returned, and I<errno> "
1906 "is set appropriately."
1910 #: build/C/man2/poll.2:272
1912 "The array given as argument was not contained in the calling program's "
1917 #: build/C/man2/poll.2:276
1918 msgid "A signal occurred before any requested event; see B<signal>(7)."
1922 #: build/C/man2/poll.2:283
1923 msgid "The I<nfds> value exceeds the B<RLIMIT_NOFILE> value."
1927 #: build/C/man2/poll.2:286
1928 msgid "There was no space to allocate file descriptor tables."
1932 #: build/C/man2/poll.2:299
1934 "The B<poll>() system call was introduced in Linux 2.1.23. The B<poll>() "
1935 "library call was introduced in libc 5.4.28 (and provides emulation using "
1936 "B<select>(2) if your kernel does not have a B<poll>() system call)."
1940 #: build/C/man2/poll.2:306
1942 "The B<ppoll>() system call was added to Linux in kernel 2.6.16. The "
1943 "B<ppoll>() library call was added in glibc 2.4."
1946 #. NetBSD 3.0 has a pollts() which is like Linux ppoll().
1948 #: build/C/man2/poll.2:312
1949 msgid "B<poll>() conforms to POSIX.1-2001. B<ppoll>() is Linux-specific."
1953 #: build/C/man2/poll.2:320
1955 "Some implementations define the nonstandard constant B<INFTIM> with the "
1956 "value -1 for use as a I<timeout> for B<poll>(). This constant is not "
1957 "provided in glibc."
1961 #: build/C/man2/poll.2:320
1967 #: build/C/man2/poll.2:334
1969 "The Linux B<ppoll>() system call modifies its I<timeout_ts> argument. "
1970 "However, the glibc wrapper function hides this behavior by using a local "
1971 "variable for the timeout argument that is passed to the system call. Thus, "
1972 "the glibc B<ppoll>() function does not modify its I<timeout_ts> argument."
1976 #: build/C/man2/poll.2:338
1978 "See the discussion of spurious readiness notifications under the BUGS "
1979 "section of B<select>(2)."
1983 #: build/C/man2/poll.2:342
1984 msgid "B<select>(2), B<select_tut>(2), B<time>(7)"