1.\" $OpenBSD: pthread_mutex_trylock.3,v 1.7 2002/02/21 20:12:19 fgsch Exp $ 2.\" 3.\" Copyright (c) 1997 Brian Cully <shmit@kublai.com> 4.\" All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. Neither the name of the author nor the names of any co-contributors 15.\" may be used to endorse or promote products derived from this software 16.\" without specific prior written permission. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND 19.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28.\" SUCH DAMAGE. 29.\" 30.\" $FreeBSD: pthread_mutex_trylock.3,v 1.5 1999/08/28 00:03:08 peter Exp $ 31.\" 32.Dd July 30, 1998 33.Dt PTHREAD_MUTEX_TRYLOCK 3 34.Os 35.Sh NAME 36.Nm pthread_mutex_trylock 37.Nd attempt to lock a mutex without blocking 38.Sh SYNOPSIS 39.Fd #include <pthread.h> 40.Ft int 41.Fn pthread_mutex_trylock "pthread_mutex_t *mutex" 42.Sh DESCRIPTION 43The 44.Fn pthread_mutex_trylock 45function locks 46.Fa mutex . 47If the mutex is already locked, 48.Fn pthread_mutex_trylock 49will not block waiting for the mutex, but will return an error condition. 50.Sh RETURN VALUES 51If successful, 52.Fn pthread_mutex_trylock 53will return zero, otherwise an error number will be returned to 54indicate the error. 55.Sh ERRORS 56.Fn pthread_mutex_trylock 57will fail if: 58.Bl -tag -width Er 59.It Bq Er EINVAL 60The value specified by 61.Fa mutex 62is invalid. 63.It Bq Er EBUSY 64.Fa mutex 65is already locked. 66.El 67.Sh SEE ALSO 68.Xr pthread_mutex_destroy 3 , 69.Xr pthread_mutex_init 3 , 70.Xr pthread_mutex_lock 3 , 71.Xr pthread_mutex_unlock 3 72.Sh STANDARDS 73.Fn pthread_mutex_trylock 74conforms to 75.St -p1003.1-96 . 76