xref: /freebsd/lib/libc/gen/sem_destroy.3 (revision f4b37ed0f8b307b1f3f0f630ca725d68f1dff30d)
1.\" Copyright (C) 2000 Jason Evans <jasone@FreeBSD.org>.
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(s), this list of conditions and the following disclaimer as
9.\"    the first lines of this file unmodified other than the possible
10.\"    addition of one or more copyright notices.
11.\" 2. Redistributions in binary form must reproduce the above copyright
12.\"    notice(s), this list of conditions and the following disclaimer in
13.\"    the documentation and/or other materials provided with the
14.\"    distribution.
15.\"
16.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
17.\" EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19.\" PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE
20.\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
23.\" BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
24.\" WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
25.\" OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
26.\" EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27.\"
28.\" $FreeBSD$
29.\"
30.Dd February 15, 2000
31.Dt SEM_DESTROY 3
32.Os
33.Sh NAME
34.Nm sem_destroy
35.Nd destroy an unnamed semaphore
36.Sh LIBRARY
37.Lb libc
38.Sh SYNOPSIS
39.In semaphore.h
40.Ft int
41.Fn sem_destroy "sem_t *sem"
42.Sh DESCRIPTION
43The
44.Fn sem_destroy
45function destroys the unnamed semaphore pointed to by
46.Fa sem .
47After a successful call to
48.Fn sem_destroy ,
49.Fa sem
50is unusable until re-initialized by another call to
51.Xr sem_init 3 .
52.Sh RETURN VALUES
53.Rv -std sem_destroy
54.Sh ERRORS
55The
56.Fn sem_destroy
57function will fail if:
58.Bl -tag -width Er
59.It Bq Er EINVAL
60The
61.Fa sem
62argument
63points to an invalid semaphore.
64.It Bq Er EBUSY
65There are currently threads blocked on the semaphore that
66.Fa sem
67points to.
68.El
69.Sh SEE ALSO
70.Xr sem_init 3
71.Sh STANDARDS
72The
73.Fn sem_destroy
74function conforms to
75.St -p1003.1-96 .
76.Pp
77.Tn POSIX
78does not define the behavior of
79.Fn sem_destroy
80if called while there are threads blocked on
81.Fa sem ,
82but this implementation is guaranteed to return \-1 and set
83.Va errno
84to
85.Er EBUSY
86if there are threads blocked on
87.Fa sem .
88