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.TH PTHREAD_RWLOCKATTR_GETPSHARED "3P" 2013 "IEEE/The Open Group" "POSIX Programmer's Manual"
.SH PROLOG
This manual page is part of the POSIX Programmer's Manual.
The Linux implementation of this interface may differ (consult
the corresponding Linux manual page for details of Linux behavior),
or the interface may not be implemented on Linux.

.SH NAME
pthread_rwlockattr_getpshared,
pthread_rwlockattr_setpshared
\(em get and set the process-shared attribute of the read-write lock
attributes object
.SH SYNOPSIS
.LP
.nf
#include <pthread.h>
.P
int pthread_rwlockattr_getpshared(const pthread_rwlockattr_t
    *restrict \fIattr\fP, int *restrict \fIpshared\fP);
int pthread_rwlockattr_setpshared(pthread_rwlockattr_t *\fIattr\fP,
    int \fIpshared\fP);
.fi
.SH DESCRIPTION
The
\fIpthread_rwlockattr_getpshared\fR()
function shall obtain the value of the
.IR process-shared
attribute from the initialized attributes object referenced by
.IR attr .
The
\fIpthread_rwlockattr_setpshared\fR()
function shall set the
.IR process-shared
attribute in an initialized attributes object referenced by
.IR attr .
.P
The
.IR process-shared
attribute shall be set to PTHREAD_PROCESS_SHARED to
permit a read-write lock to be operated upon by any thread that has
access to the memory where the read-write lock is allocated, even if
the read-write lock is allocated in memory that is shared by multiple
processes. If the
.IR process-shared
attribute is PTHREAD_PROCESS_PRIVATE, the
read-write lock shall only be operated upon by threads created within
the same process as the thread that initialized the read-write lock; if
threads of differing processes attempt to operate on such a read-write
lock, the behavior is undefined. The default value of the
.IR process-shared
attribute shall be PTHREAD_PROCESS_PRIVATE.
.P
Additional attributes, their default values, and the names of the
associated functions to get and set those attribute values are
implementation-defined.
.P
The behavior is undefined if the value specified by the
.IR attr
argument to
\fIpthread_rwlockattr_getpshared\fR()
or
\fIpthread_rwlockattr_setpshared\fR()
does not refer to an initialized read-write lock attributes object.
.SH "RETURN VALUE"
Upon successful completion, the
\fIpthread_rwlockattr_getpshared\fR()
function shall return zero and store the value of the
.IR process-shared
attribute of
.IR attr
into the object referenced by the
.IR pshared
parameter. Otherwise, an error number shall be returned to indicate the
error.
.P
If successful, the
\fIpthread_rwlockattr_setpshared\fR()
function shall return zero; otherwise, an error number shall be
returned to indicate the error.
.SH ERRORS
The
\fIpthread_rwlockattr_setpshared\fR()
function may fail if:
.TP
.BR EINVAL
The new value specified for the attribute is outside the range of legal
values for that attribute.
.P
These functions shall not return an error code of
.BR [EINTR] .
.LP
.IR "The following sections are informative."
.SH EXAMPLES
None.
.SH "APPLICATION USAGE"
None.
.SH RATIONALE
None.
.SH "FUTURE DIRECTIONS"
None.
.SH "SEE ALSO"
.IR "\fIpthread_rwlock_destroy\fR\^(\|)",
.IR "\fIpthread_rwlockattr_destroy\fR\^(\|)"
.P
The Base Definitions volume of POSIX.1\(hy2008,
.IR "\fB<pthread.h>\fP"
.SH COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 7, Copyright (C) 2013 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group.
(This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the
event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be obtained online at
http://www.unix.org/online.html .

Any typographical or formatting errors that appear
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