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.TH PTHREAD_MUTEXATTR_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_mutexattr_getpshared,
pthread_mutexattr_setpshared
\(em get and set the process-shared attribute
.SH SYNOPSIS
.LP
.nf
#include <pthread.h>
.P
int pthread_mutexattr_getpshared(const pthread_mutexattr_t
    *restrict \fIattr\fP, int *restrict \fIpshared\fP);
int pthread_mutexattr_setpshared(pthread_mutexattr_t *\fIattr\fP,
    int \fIpshared\fP);
.fi
.SH DESCRIPTION
The
\fIpthread_mutexattr_getpshared\fR()
function shall obtain the value of the
.IR process-shared
attribute from the attributes object referenced by
.IR attr .
.P
The
\fIpthread_mutexattr_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 is set to PTHREAD_PROCESS_SHARED to permit a mutex
to be operated upon by any thread that has access to the memory where
the mutex is allocated, even if the mutex is allocated in memory that
is shared by multiple processes. If the
.IR process-shared
attribute is PTHREAD_PROCESS_PRIVATE, the mutex shall only be operated
upon by threads created within the same process as the thread that
initialized the mutex; if threads of differing processes attempt to
operate on such a mutex, the behavior is undefined. The default value
of the attribute shall be PTHREAD_PROCESS_PRIVATE.
.P
The behavior is undefined if the value specified by the
.IR attr
argument to
\fIpthread_mutexattr_getpshared\fR()
or
\fIpthread_mutexattr_setpshared\fR()
does not refer to an initialized mutex attributes object.
.SH "RETURN VALUE"
Upon successful completion,
\fIpthread_mutexattr_setpshared\fR()
shall return zero; otherwise, an error number shall be returned to
indicate the error.
.P
Upon successful completion,
\fIpthread_mutexattr_getpshared\fR()
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.
.SH ERRORS
The
\fIpthread_mutexattr_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
If an implementation detects that the value specified by the
.IR attr
argument to
\fIpthread_mutexattr_getpshared\fR()
or
\fIpthread_mutexattr_setpshared\fR()
does not refer to an initialized mutex attributes object, it is
recommended that the function should fail and report an
.BR [EINVAL] 
error.
.SH "FUTURE DIRECTIONS"
None.
.SH "SEE ALSO"
.ad l
.IR "\fIpthread_cond_destroy\fR\^(\|)",
.IR "\fIpthread_create\fR\^(\|)",
.IR "\fIpthread_mutex_destroy\fR\^(\|)",
.IR "\fIpthread_mutexattr_destroy\fR\^(\|)"
.ad b
.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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