freebsd-skq/lib/libpthread/man/pthread_rwlockattr_getpshared.3

83 lines
2.8 KiB
Groff

.\" 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.
.\"
.\" $FreeBSD$
.\"
.Dd March 22, 1999
.Dt PTHREAD_RWLOCKATTR_GETPSHARED 3
.Os
.Sh NAME
.Nm pthread_rwlockattr_getpshared
.Nd get the process shared attribute
.Sh LIBRARY
.Lb libpthread
.Sh SYNOPSIS
.In pthread.h
.Ft int
.Fn pthread_rwlockattr_getpshared "const pthread_rwlockattr_t *attr" "int *pshared"
.Sh DESCRIPTION
The
.Fn pthread_rwlockattr_getpshared
function is used to get the process shared setting of a read/write
lock attribute object. The setting is returned via
.Fa pshared ,
and 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_getpshared
function will return zero. Otherwise an error number will be returned
to indicate the error.
.Sh SEE ALSO
.Xr pthread_rwlockattr_init 3 ,
.Xr pthread_rwlockattr_setpshared 3 ,
.Xr pthread_rwlock_init 3
.Sh STANDARDS
The
.Fn pthread_rwlockattr_getpshared
function is expected to conform to
.St -susv2 .
.Sh ERRORS
.Fn pthread_rwlockattr_getpshared
may fail if:
.Bl -tag -width Er
.It Bq Er EINVAL
The value specified by
.Fa attr
is invalid.
.El
.Sh HISTORY
The
.Fn pthread_rwlockattr_getpshared
function first appeared in
.Fx 3.0 .