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.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved
.TH "PTHREAD_MUTEXATTR_GETPSHARED" P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual"
.\" pthread_mutexattr_getpshared
.SH NAME
pthread_mutexattr_getpshared, pthread_mutexattr_setpshared \- get and
set the process\-shared attribute
.SH SYNOPSIS
.LP
\fB#include <pthread.h>
.br
.sp
int pthread_mutexattr_getpshared(const pthread_mutexattr_t *
.br
\ \ \ \ \ \ restrict\fP \fIattr\fP\fB, int *restrict\fP \fIpshared\fP\fB);
.br
int pthread_mutexattr_setpshared(pthread_mutexattr_t *\fP\fIattr\fP\fB,
.br
\ \ \ \ \ \ int\fP \fIpshared\fP\fB); \fP
\fB
.br
\fP
.SH DESCRIPTION
.LP
The \fIpthread_mutexattr_getpshared\fP() function shall obtain the
value of the \fIprocess-shared\fP attribute from the
attributes object referenced by \fIattr\fP. The \fIpthread_mutexattr_setpshared\fP()
function shall set the \fIprocess-shared\fP
attribute in an initialized attributes object referenced by \fIattr\fP.
.LP
The \fIprocess-shared\fP 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 \fIprocess-shared\fP 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.
.SH RETURN VALUE
.LP
Upon successful completion, \fIpthread_mutexattr_setpshared\fP() shall
return zero; otherwise, an error number shall be
returned to indicate the error.
.LP
Upon successful completion, \fIpthread_mutexattr_getpshared\fP() shall
return zero and store the value of the
\fIprocess-shared\fP attribute of \fIattr\fP into the object referenced
by the \fIpshared\fP parameter. Otherwise, an error
number shall be returned to indicate the error.
.SH ERRORS
.LP
The \fIpthread_mutexattr_getpshared\fP() and \fIpthread_mutexattr_setpshared\fP()
functions may fail if:
.TP 7
.B EINVAL
The value specified by \fIattr\fP is invalid.
.sp
.LP
The \fIpthread_mutexattr_setpshared\fP() function may fail if:
.TP 7
.B EINVAL
The new value specified for the attribute is outside the range of
legal values for that attribute.
.sp
.LP
These functions shall not return an error code of [EINTR].
.LP
\fIThe following sections are informative.\fP
.SH EXAMPLES
.LP
None.
.SH APPLICATION USAGE
.LP
None.
.SH RATIONALE
.LP
None.
.SH FUTURE DIRECTIONS
.LP
None.
.SH SEE ALSO
.LP
\fIpthread_cond_destroy\fP() , \fIpthread_create\fP() , \fIpthread_mutex_destroy\fP()
, \fIpthread_mutexattr_destroy\fP() , the Base Definitions volume
of
IEEE\ Std\ 1003.1-2001, \fI<pthread.h>\fP
.SH COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group. 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.opengroup.org/unix/online.html .
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