.\" Copyright (c) 1997 Brian Cully <shmit@kublai.com>
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.\" $FreeBSD: src/lib/libc_r/man/pthread_mutex_unlock.3,v 1.5.2.4 2001/08/17 15:42:51 ru Exp $
.\"
.Dd July 30, 1998
.Dt PTHREAD_MUTEX_UNLOCK 3
.Os
.Sh NAME
.Nm pthread_mutex_unlock
.Nd unlock a mutex
.Sh SYNOPSIS
.Fd #include <pthread.h>
.Ft int
.Fo pthread_mutex_unlock
.Fa "pthread_mutex_t *mutex"
.Fc
.Sh DESCRIPTION
If the current thread holds the lock on
.Fa mutex ,
then the
.Fn pthread_mutex_unlock
function unlocks
.Fa mutex .
.Sh RETURN VALUES
If successful,
.Fn pthread_mutex_unlock
will return zero.
Otherwise, an error number will be returned to indicate the error.
.Sh ERRORS
.Fn pthread_mutex_unlock
will fail if:
.Bl -tag -width Er
.It Bq Er EINVAL
The value specified by
.Fa mutex
is invalid.
.It Bq Er EPERM
The current thread does not hold a lock on
.Fa mutex .
.El
.Sh SEE ALSO
.Xr pthread_mutex_destroy 3 ,
.Xr pthread_mutex_init 3 ,
.Xr pthread_mutex_lock 3 ,
.Xr pthread_mutex_trylock 3
.Sh STANDARDS
.Fn pthread_mutex_unlock
conforms to
.St -p1003.1-96 .