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 August 7, 2019 29.Dt PTHREAD_MUTEX_LOCK 3 30.Os 31.Sh NAME 32.Nm pthread_mutex_lock 33.Nd lock a mutex 34.Sh LIBRARY 35.Lb libpthread 36.Sh SYNOPSIS 37.In pthread.h 38.Ft int 39.Fn pthread_mutex_lock "pthread_mutex_t *mutex" 40.Sh DESCRIPTION 41The 42.Fn pthread_mutex_lock 43function locks 44.Fa mutex . 45If the mutex is already locked, the calling thread will block until the 46mutex becomes available. 47.Sh RETURN VALUES 48If successful, 49.Fn pthread_mutex_lock 50will return zero, otherwise an error number will be returned to 51indicate the error. 52.Sh ERRORS 53The 54.Fn pthread_mutex_lock 55function will fail if: 56.Bl -tag -width "Er ENOTRECOVERABLE" 57.It Bq Er EINVAL 58The value specified by 59.Fa mutex 60is invalid. 61.It Bq Er EDEADLK 62A deadlock would occur if the thread blocked waiting for 63.Fa mutex . 64.It Bq Er EOWNERDEAD 65The argument 66.Fa mutex 67points to a robust mutex and the process containing the previous owning 68thread terminated while holding the mutex lock. 69The lock was granted to the caller and it is up to the new owner 70to make the state consistent. 71.It Bq Er ENOTRECOVERABLE 72The state protected by the 73.Fa mutex 74is not recoverable. 75.El 76.Sh SEE ALSO 77.Xr pthread_mutex_consistent 3 , 78.Xr pthread_mutex_destroy 3 , 79.Xr pthread_mutex_init 3 , 80.Xr pthread_mutex_trylock 3 , 81.Xr pthread_mutex_unlock 3 82.Sh STANDARDS 83The 84.Fn pthread_mutex_lock 85function conforms to 86.St -p1003.1-96 . 87