1.\" $NetBSD: sem.4,v 1.6 2015/08/20 11:05:06 wiz Exp $ 2.\" 3.\" Copyright (c) 2002 Tim J. Robbins 4.\" All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25.\" SUCH DAMAGE. 26.\" 27.\" From: FreeBSD: src/share/man/man4/sem.4,v 1.2 2003/06/02 11:19:23 ru 28.\" 29.Dd August 20, 2015 30.Dt SEM 4 31.Os 32.Sh NAME 33.Nm sem 34.Nd POSIX semaphores 35.Sh SYNOPSIS 36The POSIX semaphore code is included by default in all kernels. 37.Sh DESCRIPTION 38The 39.Nm 40facility provides system calls used by the standard C library 41.Pq libc 42to implement 43.Tn POSIX 44semaphores. 45.Sh SEE ALSO 46.Xr config 1 , 47.Xr sem_destroy 3 , 48.Xr sem_getvalue 3 , 49.Xr sem_init 3 , 50.Xr sem_open 3 , 51.Xr sem_post 3 , 52.Xr sem_wait 3 , 53.Xr options 4 54.Sh HISTORY 55The 56.Nm 57facility appeared as a kernel option in 58.Nx 2.0 59and became non-optional in 60.Nx 7.0 . 61