PTHREAD_MUTEXATTR_GETPSHARED(3P) POSIX Programmer's Manual PTHREAD_MUTEXATTR_GETPSHARED(3P)
PROLOG
This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the correspond-
ing Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.
NAME
pthread_mutexattr_getpshared, pthread_mutexattr_setpshared -- get and set the process-shared attribute
SYNOPSIS
#include <pthread.h>
int pthread_mutexattr_getpshared(const pthread_mutexattr_t
*restrict attr, int *restrict pshared);
int pthread_mutexattr_setpshared(pthread_mutexattr_t *attr,
int pshared);
DESCRIPTION
The pthread_mutexattr_getpshared() function shall obtain the value of the process-shared attribute from the attributes object referenced by
attr.
The pthread_mutexattr_setpshared() function shall set the process-shared attribute in an initialized attributes object referenced by attr.
The 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 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.
The behavior is undefined if the value specified by the attr argument to pthread_mutexattr_getpshared() or pthread_mutexattr_setpshared()
does not refer to an initialized mutex attributes object.
RETURN VALUE
Upon successful completion, pthread_mutexattr_setpshared() shall return zero; otherwise, an error number shall be returned to indicate the
error.
Upon successful completion, pthread_mutexattr_getpshared() shall return zero and store the value of the process-shared attribute of attr
into the object referenced by the pshared parameter. Otherwise, an error number shall be returned to indicate the error.
ERRORS
The pthread_mutexattr_setpshared() function may fail if:
EINVAL The new value specified for the attribute is outside the range of legal values for that attribute.
These functions shall not return an error code of [EINTR].
The following sections are informative.
EXAMPLES
None.
APPLICATION USAGE
None.
RATIONALE
If an implementation detects that the value specified by the attr argument to pthread_mutexattr_getpshared() or pthread_mutexattr_setp-
shared() does not refer to an initialized mutex attributes object, it is recommended that the function should fail and report an [EINVAL]
error.
FUTURE DIRECTIONS
None.
SEE ALSO
pthread_cond_destroy(), pthread_create(), pthread_mutex_destroy(), pthread_mutexattr_destroy()
The Base Definitions volume of POSIX.1-2008, <pthread.h>
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2013 Edition, Standard for Information Technol-
ogy -- 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 Stan-
dard 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 in this page are most likely to have been introduced during the conversion of the source
files to man page format. To report such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .
IEEE
/The Open Group 2013 PTHREAD_MUTEXATTR_GETPSHARED(3P)