PTHREAD_BARRIERATTR_GETPSHARED(3P)                  POSIX Programmer's Manual                 PTHREAD_BARRIERATTR_GETPSHARED(3P)



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

NAME
       pthread_barrierattr_getpshared,  pthread_barrierattr_setpshared - get and set the process-shared attribute of the barrier
       attributes object (ADVANCED REALTIME THREADS)

SYNOPSIS
       #include <pthread.h>



       int pthread_barrierattr_getpshared(const pthread_barrierattr_t *
              restrict attr, int *restrict pshared);
       int pthread_barrierattr_setpshared(pthread_barrierattr_t *attr,
              int pshared);


DESCRIPTION
       The pthread_barrierattr_getpshared() function shall obtain the value of the process-shared attribute from the  attributes
       object  referenced  by  attr.  The pthread_barrierattr_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 barrier to be operated upon by any thread  that
       has  access to the memory where the barrier is allocated. If the process-shared attribute is PTHREAD_PROCESS_PRIVATE, the
       barrier shall only be operated upon by threads created within the same process as the thread that  initialized  the  bar-
       rier;  if  threads  of  different  processes attempt to operate on such a barrier, the behavior is undefined. The default
       value of the attribute shall be PTHREAD_PROCESS_PRIVATE. Both constants PTHREAD_PROCESS_SHARED  and  PTHREAD_PROCESS_PRI-
       VATE are defined in <pthread.h>.

       Additional  attributes,  their  default  values, and the names of the associated functions to get and set those attribute
       values are implementation-defined.

RETURN VALUE
       If successful, the pthread_barrierattr_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.

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

ERRORS
       These functions may fail if:

       EINVAL The value specified by attr is invalid.


       The pthread_barrierattr_setpshared() function may fail if:

       EINVAL The  new value specified for the process-shared attribute is not one of the legal values PTHREAD_PROCESS_SHARED or
              PTHREAD_PROCESS_PRIVATE.


       These functions shall not return an error code of [EINTR].

       The following sections are informative.

EXAMPLES
       None.

APPLICATION USAGE
       The pthread_barrierattr_getpshared() and pthread_barrierattr_setpshared() functions are part of the Barriers  option  and
       need not be provided on all implementations.

RATIONALE
       None.

FUTURE DIRECTIONS
       None.

SEE ALSO
       pthread_barrier_destroy(),  pthread_barrierattr_destroy(),  pthread_barrierattr_init(),  the  Base  Definitions volume of
       IEEE Std 1003.1-2001, <pthread.h>

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, Copy-
       right (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.open-
       group.org/unix/online.html .



IEEE/The Open Group                                           2003                            PTHREAD_BARRIERATTR_GETPSHARED(3P)