1.\" Copyright (c) 1997 Brian Cully <shmit@kublai.com> 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. Neither the name of the author nor the names of any co-contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.\" $FreeBSD$ 29.\" 30.Dd February 16, 2006 31.Dt PTHREAD_COND_WAIT 3 32.Os 33.Sh NAME 34.Nm pthread_cond_wait 35.Nd wait on a condition variable 36.Sh LIBRARY 37.Lb libpthread 38.Lb libthr 39.Sh SYNOPSIS 40.In pthread.h 41.Ft int 42.Fn pthread_cond_wait "pthread_cond_t *cond" "pthread_mutex_t *mutex" 43.Sh DESCRIPTION 44The 45.Fn pthread_cond_wait 46function atomically blocks the current thread waiting on the condition 47variable specified by 48.Fa cond , 49and releases the mutex specified by 50.Fa mutex . 51The waiting thread unblocks only after another thread calls 52.Xr pthread_cond_signal 3 , 53or 54.Xr pthread_cond_broadcast 3 55with the same condition variable, and the current thread reacquires the lock 56on 57.Fa mutex . 58.Sh RETURN VALUES 59If successful, the 60.Fn pthread_cond_wait 61function will return zero. 62Otherwise an error number will be returned to 63indicate the error. 64.Sh ERRORS 65The 66.Fn pthread_cond_wait 67function will fail if: 68.Bl -tag -width Er 69.It Bq Er EINVAL 70The value specified by 71.Fa cond 72or the value specified by 73.Fa mutex 74is invalid. 75.El 76.Sh SEE ALSO 77.Xr pthread_cond_broadcast 3 , 78.Xr pthread_cond_destroy 3 , 79.Xr pthread_cond_init 3 , 80.Xr pthread_cond_signal 3 , 81.Xr pthread_cond_timedwait 3 82.Sh STANDARDS 83The 84.Fn pthread_cond_wait 85function conforms to 86.St -p1003.1-96 . 87