xref: /freebsd/share/man/man4/sem.4 (revision 06c3fb2749bda94cb5201f81ffdb8fa6c3161b2e)
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25.Dd February 7, 2014
26.Dt SEM 4
27.Os
28.Sh NAME
29.Nm sem
30.Nd POSIX semaphores
31.Sh SYNOPSIS
32To compile this driver into the kernel,
33place the following line in your
34kernel configuration file:
35.Bd -ragged -offset indent
36.Cd "options P1003_1B_SEMAPHORES"
37.Ed
38.Pp
39Alternatively, to load the driver as a
40module at boot time, place the following line in
41.Xr loader.conf 5 :
42.Bd -literal -offset indent
43sem_load="YES"
44.Ed
45.Pp
46To load the driver as a module at run-time, run the following
47command as root:
48.Bd -ragged -offset indent
49kldload sem
50.Ed
51.Sh DESCRIPTION
52The
53.Nm
54facility provides system calls used by the standard C library
55.Pq Pa libc
56to implement
57.Tn POSIX
58semaphores.
59This facility offers support for such functions as
60.Fn sem_init
61and
62.Fn sem_wait .
63It is available both as a kernel option for static inclusion and as a
64dynamic kernel module.
65.Sh SEE ALSO
66.Xr sem_destroy 3 ,
67.Xr sem_getvalue 3 ,
68.Xr sem_init 3 ,
69.Xr sem_open 3 ,
70.Xr sem_post 3 ,
71.Xr sem_wait 3 ,
72.Xr config 8 ,
73.Xr kldload 8 ,
74.Xr kldunload 8
75.Sh HISTORY
76The
77.Nm
78facility appeared in
79.Fx 5.0 .
80