xref: /freebsd/share/man/man3/pthread_mutex_unlock.3 (revision a03411e84728e9b267056fd31c7d1d9d1dc1b01e)
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.Dd April 29, 2016
29.Dt PTHREAD_MUTEX_UNLOCK 3
30.Os
31.Sh NAME
32.Nm pthread_mutex_unlock
33.Nd unlock a mutex
34.Sh LIBRARY
35.Lb libpthread
36.Sh SYNOPSIS
37.In pthread.h
38.Ft int
39.Fn pthread_mutex_unlock "pthread_mutex_t *mutex"
40.Sh DESCRIPTION
41If the current thread holds the lock on
42.Fa mutex ,
43then the
44.Fn pthread_mutex_unlock
45function unlocks
46.Fa mutex .
47.Pp
48If the argument pointed by the
49.Fa mutex
50is a robust mutex in the inconsistent state, and the call to
51.Fn pthread_mutex_consistent
52function was not done prior to unlocking, further locking attempts on
53the mutex
54.Fa mutex
55are denied and locking functions return
56.Er ENOTRECOVERABLE
57error.
58.Sh RETURN VALUES
59If successful,
60.Fn pthread_mutex_unlock
61will return zero, otherwise an error number will be returned to
62indicate the error.
63.Sh ERRORS
64The
65.Fn pthread_mutex_unlock
66function will fail if:
67.Bl -tag -width Er
68.It Bq Er EINVAL
69The value specified by
70.Fa mutex
71is invalid.
72.It Bq Er EPERM
73The current thread does not hold a lock on
74.Fa mutex .
75.El
76.Sh SEE ALSO
77.Xr pthread_mutex_destroy 3 ,
78.Xr pthread_mutex_init 3 ,
79.Xr pthread_mutex_lock 3 ,
80.Xr pthread_mutex_trylock 3
81.Sh STANDARDS
82The
83.Fn pthread_mutex_unlock
84function conforms to
85.St -p1003.1-96 .
86