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 July 28, 1998 31.Dt PTHREAD_COND_WAIT 3 32.Os BSD 4 33.Sh NAME 34.Nm pthread_cond_wait 35.Nd wait on a condition variable 36.Sh SYNOPSIS 37.Fd #include <pthread.h> 38.Ft int 39.Fn pthread_cond_wait "pthread_cond_t *cond" "pthread_mutex_t *mutex" 40.Sh DESCRIPTION 41The 42.Fn pthread_cond_wait 43function atomically blocks the current thread waiting on the condition 44variable specified by 45.Fa cond , 46and unblocks the mutex specified by 47.Fa mutex . 48The waiting thread unblocks only after another thread calls 49.Xr pthread_cond_signal 3 , or 50.Xr pthread_cond_broadcast 3 51with the same condition variable, and the current thread requires the lock 52on 53.Fa mutex . 54.Sh RETURN VALUES 55If successful, the 56.Fn pthread_cond_wait 57function will return zero. Otherwise an error number will be returned to 58indicate the error. 59.Sh ERRORS 60.Fn pthread_cond_wait 61will fail if: 62.Bl -tag -width Er 63.It Bq Er EINVAL 64The value specified by 65.Fa cond 66or the value specified by 67.Fa mutex 68is invalid. 69.El 70.Pp 71.Sh SEE ALSO 72.Xr pthread_cond_broadcast 3 , 73.Xr pthread_cond_destroy 3 , 74.Xr pthread_cond_init 3 , 75.Xr pthread_cond_signal 3 , 76.Xr pthread_cond_timedwait 3 77.Sh STANDARDS 78.Fn pthread_cond_wait 79conforms to ISO/IEC 9945-1 ANSI/IEEE 80.Pq Dq Tn POSIX 81Std 1003.1 Second Edition 1996-07-12. 82