.\" $OpenBSD: pthread_rwlockattr_getpshared.3,v 1.10 2013/06/05 03:44:50 tedu Exp $
.\" Copyright (c) 1998 Alex Nash
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.\" $FreeBSD: pthread_rwlockattr_getpshared.3,v 1.4 1999/08/28 00:03:10 peter Exp $
.\"
.Dd $Mdocdate: June 5 2013 $
.Dt PTHREAD_RWLOCKATTR_GETPSHARED 3
.Os
.Sh NAME
.Nm pthread_rwlockattr_getpshared
.Nd get the process shared attribute
.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 -hang -offset flag -width 123456789012345678901234
.It Ar 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 Ar 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 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 SEE ALSO
.Xr pthread_rwlock_init 3 ,
.Xr pthread_rwlockattr_init 3 ,
.Xr pthread_rwlockattr_setpshared 3
.Sh STANDARDS
The
.Fn pthread_rwlockattr_getpshared
function is expected to conform to
.St -susv2 .
.Sh HISTORY
The
.Fn pthread_rwlockattr_getpshared
function first appeared in
.Fx 3.0
and
.Ox 2.5 .