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.\" $FreeBSD: head/share/man/man3/pthread_mutex_unlock.3 300043 2016-05-17 09:56:22Z kib $
.\"
.Dd April 29, 2016
.Dt PTHREAD_MUTEX_UNLOCK 3
.Os
.Sh NAME
.Nm pthread_mutex_unlock
.Nd unlock a mutex
.Sh LIBRARY
.Lb libpthread
.Sh SYNOPSIS
.In pthread.h
.Ft int
.Fn pthread_mutex_unlock "pthread_mutex_t *mutex"
.Sh DESCRIPTION
If the current thread holds the lock on
.Fa mutex ,
then the
.Fn pthread_mutex_unlock
function unlocks
.Fa mutex .
.Pp
If the argument pointed by the
.Fa mutex
is a robust mutex in the inconsistent state, and the call to
.Fn pthread_mutex_consistent
function was not done prior to unlocking, further locking attempts on
the mutex
.Fa mutex
are denied and locking functions return
.Er ENOTRECOVERABLE
error.
.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
The
.Fn pthread_mutex_unlock
function 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
The
.Fn pthread_mutex_unlock
function conforms to
.St -p1003.1-96 .