PTHREAD_CONDATTR_GETPSHARED(P3O)SIX Programmer's ManPuTaHlREAD_CONDATTR_GETPSHARED(3)



PROLOG
       This manual page is part of the POSIX Programmer's Manual.  The OS
       implementation of this interface may differ (consult the corresponding
       OS manual page for details of OS behavior), or the interface may not be
       implemented on OS.

NAME
       pthread_condattr_getpshared, pthread_condattr_setpshared -- get and set
       the process-shared condition variable attributes

SYNOPSIS
       #include <pthread.h>

       int pthread_condattr_getpshared(const pthread_condattr_t *restrict attr,
           int *restrict pshared);
       int pthread_condattr_setpshared(pthread_condattr_t *attr,
           int pshared);

DESCRIPTION
       The pthread__condattr__getpshared() function shall obtain the value of
       the process-shared attribute from the attributes object referenced by
       attr.

       The pthread__condattr__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 condition variable to be operated upon by any thread that has access
       to the memory where the condition variable is allocated, even if the
       condition variable is allocated in memory that is shared by multiple
       processes. See Section 2.9.9, Synchronization Object Copies and
       Alternative Mappings for further requirements. The default value of the
       attribute is PTHREAD_PROCESS_PRIVATE.

       The behavior is undefined if the value specified by the attr argument
       to pthread__condattr__getpshared() or pthread__condattr__setpshared() does
       not refer to an initialized condition variable attributes object.

RETURN VALUE
       If successful, the pthread__condattr__setpshared() function shall return
       zero; otherwise, an error number shall be returned to indicate the
       error.

       If successful, the pthread__condattr__getpshared() function 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__condattr__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__condattr__getpshared() or
       pthread__condattr__setpshared() does not refer to an initialized
       condition variable attributes object, it is recommended that the
       function should fail and report an [EINVAL] error.

FUTURE DIRECTIONS
       None.

SEE ALSO
       pthread__create(), pthread__cond__destroy(), pthread__condattr__destroy(),
       pthread__mutex__destroy()

       The Base Definitions volume of POSIX.1-2017, <pthread.h>

COPYRIGHT
       Portions of this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1-2017, Standard for Information Technology --
       Portable Operating System Interface (POSIX), The Open Group Base
       Specifications Issue 7, 2018 Edition, Copyright (C) 2018 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 .

       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                  2017       PTHREAD_CONDATTR_GETPSHARED(3)
