1.\" Copyright (c) 1998 Alex Nash 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.\" 13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23.\" SUCH DAMAGE. 24.\" 25.Dd August 4, 1998 26.Dt PTHREAD_RWLOCK_UNLOCK 3 27.Os 28.Sh NAME 29.Nm pthread_rwlock_unlock 30.Nd release a read/write lock 31.Sh LIBRARY 32.Lb libpthread 33.Sh SYNOPSIS 34.In pthread.h 35.Ft int 36.Fn pthread_rwlock_unlock "pthread_rwlock_t *lock" 37.Sh DESCRIPTION 38The 39.Fn pthread_rwlock_unlock 40function is used to release the read/write lock previously obtained by 41.Fn pthread_rwlock_rdlock , 42.Fn pthread_rwlock_wrlock , 43.Fn pthread_rwlock_tryrdlock , 44or 45.Fn pthread_rwlock_trywrlock . 46.Sh RETURN VALUES 47If successful, the 48.Fn pthread_rwlock_unlock 49function will return zero. 50Otherwise an error number will be returned 51to indicate the error. 52.Pp 53The results are undefined if 54.Fa lock 55is not held by the calling thread. 56.Sh ERRORS 57The 58.Fn pthread_rwlock_unlock 59function may fail if: 60.Bl -tag -width Er 61.It Bq Er EINVAL 62The value specified by 63.Fa lock 64is invalid. 65.It Bq Er EPERM 66The current thread does not own the read/write lock. 67.El 68.Sh SEE ALSO 69.Xr pthread_rwlock_rdlock 3 , 70.Xr pthread_rwlock_wrlock 3 71.Sh STANDARDS 72The 73.Fn pthread_rwlock_unlock 74function is expected to conform to 75.St -susv2 . 76.Sh HISTORY 77The 78.Fn pthread_rwlock_unlock 79function first appeared in 80.Fx 3.0 . 81