xref: /freebsd/lib/libc/gen/sem_destroy.3 (revision e9ac41698b2f322d55ccf9da50a3596edb2c1800)
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28.Dd February 15, 2000
29.Dt SEM_DESTROY 3
30.Os
31.Sh NAME
32.Nm sem_destroy
33.Nd destroy an unnamed semaphore
34.Sh LIBRARY
35.Lb libc
36.Sh SYNOPSIS
37.In semaphore.h
38.Ft int
39.Fn sem_destroy "sem_t *sem"
40.Sh DESCRIPTION
41The
42.Fn sem_destroy
43function destroys the unnamed semaphore pointed to by
44.Fa sem .
45After a successful call to
46.Fn sem_destroy ,
47.Fa sem
48is unusable until re-initialized by another call to
49.Xr sem_init 3 .
50.Sh RETURN VALUES
51.Rv -std sem_destroy
52.Sh ERRORS
53The
54.Fn sem_destroy
55function will fail if:
56.Bl -tag -width Er
57.It Bq Er EINVAL
58The
59.Fa sem
60argument
61points to an invalid semaphore.
62.It Bq Er EBUSY
63There are currently threads blocked on the semaphore that
64.Fa sem
65points to.
66.El
67.Sh SEE ALSO
68.Xr sem_init 3
69.Sh STANDARDS
70The
71.Fn sem_destroy
72function conforms to
73.St -p1003.1-96 .
74.Pp
75.Tn POSIX
76does 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
83.Er EBUSY
84if there are threads blocked on
85.Fa sem .
86