1.\" Copyright (c) 2002 Tim J. Robbins 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23.\" SUCH DAMAGE. 24.\" 25.\" $FreeBSD$ 26.\" 27.Dd May 3, 2011 28.Dt SEM 4 29.Os 30.Sh NAME 31.Nm sem 32.Nd POSIX semaphores 33.Sh SYNOPSIS 34To compile this driver into the kernel, 35place the following lines in your 36kernel configuration file: 37.Bd -ragged -offset indent 38.Cd "options P1003_1B_SEMAPHORES" 39.Ed 40.Pp 41Alternatively, to load the driver as a 42module at boot time, place the following line in 43.Xr loader.conf 5 : 44.Bd -literal -offset indent 45sem_load="YES" 46.Ed 47.Pp 48.Dl "kldload sem" 49.Sh DESCRIPTION 50The 51.Nm 52facility provides system calls used by the standard C library 53.Pq Pa libc 54to implement 55.Tn POSIX 56semaphores. 57This facility offers support for such functions as 58.Fn sem_init 59and 60.Fn sem_wait . 61It is available both as a kernel option for static inclusion and as a 62dynamic kernel module. 63.Sh SEE ALSO 64.Xr sem_destroy 3 , 65.Xr sem_getvalue 3 , 66.Xr sem_init 3 , 67.Xr sem_open 3 , 68.Xr sem_post 3 , 69.Xr sem_wait 3 , 70.Xr config 8 , 71.Xr kldload 8 , 72.Xr kldunload 8 73.Sh HISTORY 74The 75.Nm 76facility appeared in 77.Fx 5.0 . 78