xref: /freebsd/lib/libc/gen/sem_destroy.3 (revision c23155a43a8fbd8404b4d7bca71c292e92fb4870)
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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 LIBRARY
36.Lb libc_r
37.Sh SYNOPSIS
38.Fd #include <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 unuseable until re-initialized by another call to
50.Fn sem_init .
51.Sh RETURN VALUES
52If successful,
53.Fn sem_destroy
54returns 0.  Otherwise, -1 is returned and
55.Va errno
56is set to indicate the type of
57error.
58.Sh ERRORS
59.Fn sem_destroy
60will fail if:
61.Bl -tag -width Er
62.It Bq Er EINVAL
63.Fa sem
64points to an invalid semaphore.
65.It Bq Er EBUSY
66There are currently threads blocked on the semaphore that
67.Fa sem
68points to.
69.El
70.Sh SEE ALSO
71.Xr sem_init 3
72.Sh STANDARDS
73.Fn sem_destroy
74conforms to ISO/IEC 9945-1 ANSI/IEEE
75.Pq Dq Tn POSIX
76Std 1003.1 1996 Edition.
77.Pp
78POSIX does 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