xref: /freebsd/lib/libc/gen/sem_destroy.3 (revision 8ddb146abcdf061be9f2c0db7e391697dafad85c)
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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