PTHREAD_BARRIERATTR_GETPSHAPOSIX)Programmer'sPTHREAD_BARRIERATTR_GETPSHARED(P)



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 pro-
       cess-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 mem-
       ory  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 barrier; 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_PRO-
       CESS_SHARED and PTHREAD_PROCESS_PRIVATE are defined in <pthread.h>.

       Additional attributes, their default values, and the names of the asso-
       ciated functions to get and set those attribute values are  implementa-
       tion-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_PRO-
              CESS_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_setp-
       shared() functions are part of the Barriers option and need not be pro-
       vided 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,  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 .



IEEE/The Open Group                  2003    PTHREAD_BARRIERATTR_GETPSHARED(P)