.\" Copyright (C) 2000 Jason Evans <jasone@canonware.com>.
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.\" $FreeBSD$
.Dd February 15, 2000
.Dt SEM_DESTROY 3
.Os
.Sh NAME
.Nm sem_destroy
.Nd destroy an unnamed semaphore
.Sh SYNOPSIS
.Fd #include <semaphore.h>
.Ft int
.Fn sem_destroy "sem_t *sem"
.Sh DESCRIPTION
The
.Fn sem_destroy
function destroys the unnamed semaphore pointed to by
.Fa sem .
After a successful call to
.Fn sem_destroy ,
.Fa sem
is unuseable until re-initialized by another call to
.Fn sem_init .
.Sh RETURN VALUES
If successful,
.Fn sem_destroy
returns 0.  Otherwise, -1 is returned and
.Va errno
is set to indicate the type of
error.
.Sh ERRORS
.Fn sem_destroy
will fail if:
.Bl -tag -width Er
.It Bq Er EINVAL
.Fa sem
points to an invalid semaphore.
.It Bq Er EBUSY
There are currently threads blocked on the semaphore that
.Fa sem
points to.
.El
.Sh SEE ALSO
.Xr sem_init 3
.Sh STANDARDS
.Fn sem_destroy
conforms to ISO/IEC 9945-1 ANSI/IEEE
.Pq Dq Tn POSIX
Std 1003.1 1996 Edition.
.Pp
POSIX does not define the behavior of
.Fn sem_destroy
if called while there are threads blocked on
.Fa sem ,
but this implementation is guaranteed to return -1 and set
.Va errno
to EBUSY if there are threads blocked on
.Fa sem .