.\" Portions Copyright (c) 2001 Apple Computer, Inc. All Rights Reserved.
.\" Copyright (c) 1997 Brian Cully <shmit@kublai.com>
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 3. Neither the name of the author nor the names of any co-contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\" $FreeBSD: src/lib/libc_r/man/pthread_cond_wait.3,v 1.8.2.4 2001/08/17 15:42:51 ru Exp $
.\"
.Dd November 5, 2001
.Dt PTHREAD_COND_WAIT 3
.Os Darwin
.Sh NAME
.Nm pthread_cond_wait
.Nd wait on a condition variable
.Sh SYNOPSIS
.Fd #include <pthread.h>
.Ft int
.Fo pthread_cond_wait
.Fa "pthread_cond_t *restrict cond"
.Fa "pthread_mutex_t *restrict mutex"
.Fc
.Sh DESCRIPTION
The
.Fn pthread_cond_wait
function atomically unlocks the 
.Fa mutex 
argument and waits on the 
.Fa cond
argument.
.Sh RETURN VALUES
If successful, the
.Fn pthread_cond_wait
function will return zero.
Otherwise, an error number will be returned to indicate the error.
.Sh ERRORS
.Fn pthread_cond_wait
will fail if:
.Bl -tag -width Er
.It Bq Er EINVAL
The value specified by
.Fa cond
or the value specified by
.Fa mutex
is invalid.
.El
.Sh SEE ALSO
.Xr pthread_cond_broadcast 3 ,
.Xr pthread_cond_destroy 3 ,
.Xr pthread_cond_init 3 ,
.Xr pthread_cond_signal 3 ,
.Xr pthread_cond_timedwait 3
.Sh STANDARDS
.Fn pthread_cond_wait
conforms to
.St -p1003.1-96 .