diff options
| author | Jacob McDonnell <jacob@jacobmcdonnell.com> | 2026-04-25 19:54:44 -0400 |
|---|---|---|
| committer | Jacob McDonnell <jacob@jacobmcdonnell.com> | 2026-04-25 19:54:44 -0400 |
| commit | a9157ce950dfe2fc30795d43b9d79b9d1bffc48b (patch) | |
| tree | 9df484304b560466d145e662c1c254ff0e9ae0ba /static/openbsd/man3/sem_wait.3 | |
| parent | 160aa82b2d39c46ad33723d7d909cb4972efbb03 (diff) | |
docs: Added All OpenBSD Manuals
Diffstat (limited to 'static/openbsd/man3/sem_wait.3')
| -rw-r--r-- | static/openbsd/man3/sem_wait.3 | 133 |
1 files changed, 133 insertions, 0 deletions
diff --git a/static/openbsd/man3/sem_wait.3 b/static/openbsd/man3/sem_wait.3 new file mode 100644 index 00000000..db0235bb --- /dev/null +++ b/static/openbsd/man3/sem_wait.3 @@ -0,0 +1,133 @@ +.\" $OpenBSD: sem_wait.3,v 1.11 2025/06/07 00:16:52 schwarze Exp $ +.\" +.\" Copyright (C) 2000 Jason Evans <jasone@FreeBSD.org>. +.\" All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice(s), this list of conditions and the following disclaimer as +.\" the first lines of this file unmodified other than the possible +.\" addition of one or more copyright notices. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice(s), this list of conditions and the following disclaimer in +.\" the documentation and/or other materials provided with the +.\" distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY +.\" EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR +.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE +.\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR +.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF +.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR +.\" BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, +.\" WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE +.\" OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, +.\" EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +.\" +.\" $FreeBSD: src/lib/libc_r/man/sem_wait.3,v 1.8 2001/10/01 16:09:09 ru Exp $ +.Dd $Mdocdate: June 7 2025 $ +.Dt SEM_WAIT 3 +.Os +.Sh NAME +.Nm sem_wait , +.Nm sem_timedwait , +.Nm sem_trywait +.Nd decrement (lock) a semaphore +.Sh SYNOPSIS +.Lb libpthread +.In semaphore.h +.Ft int +.Fn sem_wait "sem_t *sem" +.Ft int +.Fn sem_timedwait "sem_t *sem" "const struct timespec *abstime" +.Ft int +.Fn sem_trywait "sem_t *sem" +.Sh DESCRIPTION +The +.Fn sem_wait +function decrements (locks) the semaphore pointed to by +.Fa sem , +but blocks if the value of +.Fa sem +is zero, until the value is non-zero and the value can be decremented. +.Pp +The +.Fn sem_timedwait +function decrements (locks) the semaphore pointed to by +.Fa sem , +but blocks if the value of +.Fa sem +is zero, until either the value is non-zero and can be decremented +or the system time specified by +.Fa abstime +is reached. +.Pp +The +.Fn sem_trywait +function decrements (locks) the semaphore pointed to by +.Fa sem +only if the value is non-zero. +Otherwise, the semaphore is not decremented and +an error is returned. +.Sh RETURN VALUES +.Rv -std sem_wait sem_timedwait sem_trywait +.Sh ERRORS +.Fn sem_wait , +.Fn sem_timedwait , +and +.Fn sem_trywait +will fail if: +.Bl -tag -width Er +.It Bq Er EINVAL +.Fa sem +points to an invalid semaphore. +.El +.Pp +Additionally, +.Fn sem_wait +and +.Fn sem_timedwait +will fail if: +.Bl -tag -width Er +.It Bq Er EINTR +The call was interrupted by a signal. +.El +.Pp +Additionally, +.Fn sem_timedwait +will fail if: +.Bl -tag -width Er +.It Bq Er EINVAL +.Fa abstime +was +.Dv NULL +or specified a nanosecond value less than zero or greater than 1000 million. +.It Bq Er ETIMEDOUT +The semaphore value was zero and could not be decremented before +.Fa abstime +was reached. +.El +.Pp +Additionally, +.Fn sem_trywait +will fail if: +.Bl -tag -width Er +.It Bq Er EAGAIN +The semaphore value was zero, and thus could not be decremented. +.El +.Sh SEE ALSO +.Xr sem_destroy 3 , +.Xr sem_getvalue 3 , +.Xr sem_init 3 , +.Xr sem_open 3 , +.Xr sem_post 3 +.Sh STANDARDS +.Fn sem_wait , +.Fn sem_timedwait , +and +.Fn sem_trywait +conform to +.St -p1003.1-2008 . |
