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| author | Alejandro Colomar <alx.manpages@gmail.com> | 2022-09-05 23:03:38 +0200 |
|---|---|---|
| committer | Alejandro Colomar <alx.manpages@gmail.com> | 2022-09-05 23:03:47 +0200 |
| commit | 70ac1c4785fc1e158ab2349a962dba2526bf4fbc (patch) | |
| tree | bff270e2496dd284bccfc1271b43946f5d225224 /man/man3/sem_post.3 | |
| parent | 5423a6f86b2b920a5f3e8cf8d759b513050f2d33 (diff) | |
| download | man-pages-70ac1c4785fc1e158ab2349a962dba2526bf4fbc.tar.gz | |
src.mk, All pages: Move man* to man/
The root of the repository is becoming a bit overpopulated and
unorganized, due to the recent addition of more mandirs, and more
informative and configuration files too. Let's create a specific
mandir <man/> that contains the mandirs <man[1-8]*>.
Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com>
Diffstat (limited to 'man/man3/sem_post.3')
| -rw-r--r-- | man/man3/sem_post.3 | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/man/man3/sem_post.3 b/man/man3/sem_post.3 new file mode 100644 index 0000000000..d64e9b43ae --- /dev/null +++ b/man/man3/sem_post.3 @@ -0,0 +1,73 @@ +.\" Copyright (C) 2006 Michael Kerrisk <mtk.manpages@gmail.com> +.\" +.\" SPDX-License-Identifier: Linux-man-pages-copyleft +.\" +.TH SEM_POST 3 2021-03-22 "Linux man-pages (unreleased)" +.SH NAME +sem_post \- unlock a semaphore +.SH LIBRARY +POSIX threads library +.RI ( libpthread ", " \-lpthread ) +.SH SYNOPSIS +.nf +.B #include <semaphore.h> +.PP +.BI "int sem_post(sem_t *" sem ); +.fi +.SH DESCRIPTION +.BR sem_post () +increments (unlocks) the semaphore pointed to by +.IR sem . +If the semaphore's value consequently becomes greater than zero, +then another process or thread blocked in a +.BR sem_wait (3) +call will be woken up and proceed to lock the semaphore. +.SH RETURN VALUE +.BR sem_post () +returns 0 on success; +on error, the value of the semaphore is left unchanged, +\-1 is returned, and +.I errno +is set to indicate the error. +.SH ERRORS +.TP +.B EINVAL +.I sem +is not a valid semaphore. +.TP +.B EOVERFLOW +.\" Added in POSIX.1-2008 TC1 (Austin Interpretation 213) +The maximum allowable value for a semaphore would be exceeded. +.SH ATTRIBUTES +For an explanation of the terms used in this section, see +.BR attributes (7). +.ad l +.nh +.TS +allbox; +lbx lb lb +l l l. +Interface Attribute Value +T{ +.BR sem_post () +T} Thread safety MT-Safe +.TE +.hy +.ad +.sp 1 +.SH STANDARDS +POSIX.1-2001. +.SH NOTES +.BR sem_post () +is async-signal-safe: +it may be safely called within a signal handler. +.SH EXAMPLES +See +.BR sem_wait (3) +and +.BR shm_open (3). +.SH SEE ALSO +.BR sem_getvalue (3), +.BR sem_wait (3), +.BR sem_overview (7), +.BR signal\-safety (7) |