xref: /freebsd/lib/libc/gen/sem_destroy.3 (revision b0a1b4f80919d734dda03410df0cabf7297dfb68)
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28.\" $FreeBSD$
29.Dd February 15, 2000
30.Dt SEM_DESTROY 3
31.Os
32.Sh NAME
33.Nm sem_destroy
34.Nd destroy an unnamed semaphore
35.Sh SYNOPSIS
36.Fd #include <semaphore.h>
37.Ft int
38.Fn sem_destroy "sem_t *sem"
39.Sh DESCRIPTION
40The
41.Fn sem_destroy
42function destroys the unnamed semaphore pointed to by
43.Fa sem .
44After a successful call to
45.Fn sem_destroy ,
46.Fa sem
47is unuseable until re-initialized by another call to
48.Fn sem_init .
49.Sh RETURN VALUES
50If successful,
51.Fn sem_destroy
52returns 0.  Otherwise, -1 is returned and
53.Va errno
54is set to indicate the type of
55error.
56.Sh ERRORS
57.Fn sem_destroy
58will fail if:
59.Bl -tag -width Er
60.It Bq Er EINVAL
61.Fa sem
62points to an invalid semaphore.
63.It Bq Er EBUSY
64There are currently threads blocked on the semaphore that
65.Fa sem
66points to.
67.El
68.Sh SEE ALSO
69.Xr sem_init 3
70.Sh STANDARDS
71.Fn sem_destroy
72conforms to ISO/IEC 9945-1 ANSI/IEEE
73.Pq Dq Tn POSIX
74Std 1003.1 1996 Edition.
75.Pp
76POSIX does not define the behavior of
77.Fn sem_destroy
78if called while there are threads blocked on
79.Fa sem ,
80but this implementation is guaranteed to return -1 and set
81.Va errno
82to EBUSY if there are threads blocked on
83.Fa sem .
84