.\" Copyright (c) 1997 Brian Cully <shmit@kublai.com>
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.\" $FreeBSD: src/share/man/man3/pthread_mutex_trylock.3,v 1.15 2007/10/22 10:08:00 ru Exp $
.\" $DragonFly: src/lib/libc_r/man/pthread_mutex_trylock.3,v 1.2 2003/06/17 04:26:48 dillon Exp $
.\"
.Dd July 10, 2009
.Dt PTHREAD_MUTEX_TRYLOCK 3
.Os
.Sh NAME
.Nm pthread_mutex_trylock
.Nd attempt to lock a mutex without blocking
.Sh LIBRARY
.Lb libpthread
.Sh SYNOPSIS
.In pthread.h
.Ft int
.Fn pthread_mutex_trylock "pthread_mutex_t *mutex"
.Sh DESCRIPTION
The
.Fn pthread_mutex_trylock
function locks
.Fa mutex .
If the mutex is already locked,
.Fn pthread_mutex_trylock
will not block waiting for the mutex, but will return an error condition.
.Sh RETURN VALUES
If successful,
.Fn pthread_mutex_trylock
will return zero, otherwise an error number will be returned to
indicate the error.
.Sh ERRORS
The
.Fn pthread_mutex_trylock
function will fail if:
.Bl -tag -width Er
.It Bq Er EINVAL
The value specified by
.Fa mutex
is invalid.
.It Bq Er EBUSY
.Fa Mutex
is already locked.
.El
.Sh SEE ALSO
.Xr pthread_mutex_destroy 3 ,
.Xr pthread_mutex_init 3 ,
.Xr pthread_mutex_lock 3 ,
.Xr pthread_mutex_unlock 3
.Sh STANDARDS
The
.Fn pthread_mutex_trylock
function conforms to
.St -p1003.1-96 .