.\" Copyright (c) 1998 Alex Nash .\" 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. .\" .\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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. .\" .Dd May 31, 2016 .Dt PTHREAD_RWLOCKATTR_SETPSHARED 3 .Os .Sh NAME .Nm pthread_rwlockattr_setpshared .Nd set the process shared attribute .Sh LIBRARY .Lb libpthread .Sh SYNOPSIS .In pthread.h .Ft int .Fn pthread_rwlockattr_setpshared "pthread_rwlockattr_t *attr" "int pshared" .Sh DESCRIPTION The .Fn pthread_rwlockattr_setpshared function sets the process shared attribute of .Fa attr to the value referenced by .Fa pshared . The .Fa pshared argument may be one of two values: .Bl -tag -width PTHREAD_PROCESS_PRIVATE .It Dv PTHREAD_PROCESS_SHARED Any thread of any process that has access to the memory where the read/write lock resides can manipulate the lock. .It Dv PTHREAD_PROCESS_PRIVATE Only threads created within the same process as the thread that initialized the read/write lock can manipulate the lock. This is the default value. .El .Sh RETURN VALUES If successful, the .Fn pthread_rwlockattr_setpshared function will return zero. Otherwise an error number will be returned to indicate the error. .Sh ERRORS The .Fn pthread_rwlockattr_setpshared function will fail if: .Bl -tag -width Er .It Bq Er EINVAL The value specified by .Fa attr or .Fa pshared is invalid. .El .Sh SEE ALSO .Xr pthread_rwlock_init 3 , .Xr pthread_rwlockattr_getpshared 3 , .Xr pthread_rwlockattr_init 3 .Sh STANDARDS The .Fn pthread_rwlockattr_setpshared function is expected to conform to .St -susv2 . .Sh HISTORY The .Fn pthread_rwlockattr_setpshared function first appeared in .Fx 3.0 . Support for process-shared read/write locks appeared in .Fx 11.0 .