xref: /dragonfly/lib/libpthread/sem_destroy.3 (revision c9c5aa9e)
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28.\" $FreeBSD: src/lib/libc_r/man/sem_destroy.3,v 1.1.2.8 2002/12/29 16:35:35 schweikh Exp $
29.Dd April 15, 2009
30.Dt SEM_DESTROY 3
31.Os
32.Sh NAME
33.Nm sem_destroy
34.Nd destroy an unnamed semaphore
35.Sh LIBRARY
36.Lb libpthread
37.Sh SYNOPSIS
38.In semaphore.h
39.Ft int
40.Fn sem_destroy "sem_t *sem"
41.Sh DESCRIPTION
42The
43.Fn sem_destroy
44function destroys the unnamed semaphore pointed to by
45.Fa sem .
46After a successful call to
47.Fn sem_destroy ,
48.Fa sem
49is unusable until re-initialized by another call to
50.Fn sem_init .
51.Sh RETURN VALUES
52.Rv -std sem_destroy
53.Sh ERRORS
54.Fn sem_destroy
55will fail if:
56.Bl -tag -width Er
57.It Bq Er EINVAL
58.Fa sem
59points to an invalid semaphore.
60.It Bq Er EBUSY
61There are currently threads blocked on the semaphore that
62.Fa sem
63points to.
64.El
65.Sh SEE ALSO
66.Xr sem_init 3
67.Sh STANDARDS
68.Fn sem_destroy
69conforms to
70.St -p1003.1-96 .
71.Pp
72POSIX does not define the behavior of
73.Fn sem_destroy
74if called while there are threads blocked on
75.Fa sem ,
76but this implementation is guaranteed to return -1 and set
77.Va errno
78to
79.Er EBUSY
80if there are threads blocked on
81.Fa sem .
82