.\" $OpenBSD: pthread_join.3,v 1.8 2002/05/01 08:03:30 mpech Exp $
.\"
.\" Copyright (c) 1996-1998 John Birrell <jb@cimlogic.com.au>.
.\" 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. All advertising materials mentioning features or use of this software
.\"    must display the following acknowledgement:
.\"	This product includes software developed by John Birrell.
.\" 4. 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: pthread_join.3,v 1.6 1999/08/28 00:03:06 peter Exp $
.\"
.Dd April 4, 1996
.Dt PTHREAD_JOIN 3
.Os
.Sh NAME
.Nm pthread_join
.Nd wait for thread termination
.Sh SYNOPSIS
.Fd #include <pthread.h>
.Ft int
.Fn pthread_join "pthread_t thread" "void **value_ptr"
.Sh DESCRIPTION
The
.Fn pthread_join
function suspends execution of the calling thread until the target
.Fa thread
terminates unless the target
.Fa thread
has already terminated.
.Pp
On return from a successful
.Fn pthread_join
call with a non-NULL
.Fa value_ptr
argument, the value passed to
.Fn pthread_exit
by the terminating thread is stored in the location referenced by
.Fa value_ptr .
When a
.Fn pthread_join
returns successfully, the target thread has been terminated.
The results of multiple simultaneous calls to
.Fn pthread_join
specifying the same target thread are undefined.
If the thread calling
.Fn pthread_join
is cancelled, then the target thread is not detached.
.Pp
A thread that has exited but remains unjoined counts against
[_POSIX_THREAD_THREADS_MAX].
.Sh RETURN VALUES
If successful, the
.Fn pthread_join
function will return zero.
Otherwise an error number will be returned to indicate the error.
.Sh ERRORS
.Fn pthread_join
will fail if:
.Bl -tag -width Er
.It Bq Er EINVAL
The implementation has detected that the value specified by
.Fa thread
does not refer to a joinable thread.
.It Bq Er ESRCH
No thread could be found corresponding to that specified by the given
thread ID,
.Fa thread .
.It Bq Er EDEADLK
A deadlock was detected or the value of
.Fa thread
specifies the calling thread.
.El
.Sh SEE ALSO
.Xr wait 2 ,
.Xr pthread_create 3
.Sh STANDARDS
.Fn pthread_join
conforms to
.St -p1003.1-96 .