xref: /freebsd/lib/libc/gen/sem_destroy.3 (revision 1669d8afc64812c8d2d1d147ae1fd42ff441e1b1)
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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.Xr sem 4
72.Sh STANDARDS
73The
74.Fn sem_destroy
75function conforms to
76.St -p1003.1-96 .
77.Pp
78.Tn POSIX
79does not define the behavior of
80.Fn sem_destroy
81if called while there are threads blocked on
82.Fa sem ,
83but this implementation is guaranteed to return \-1 and set
84.Va errno
85to
86.Er EBUSY
87if there are threads blocked on
88.Fa sem .
89