bionic (3) pthread_rwlockattr_getpshared.3posix.gz

Provided by: manpages-posix-dev_2013a-2_all bug

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


NAME
       pthread_rwlockattr_getpshared,  pthread_rwlockattr_setpshared  — get and set the process-shared attribute
       of the read-write lock attributes object


SYNOPSIS
       #include <pthread.h>

       int pthread_rwlockattr_getpshared(const pthread_rwlockattr_t
           *restrict attr, int *restrict pshared);
       int pthread_rwlockattr_setpshared(pthread_rwlockattr_t *attr,
           int pshared);


DESCRIPTION
       The pthread_rwlockattr_getpshared() function shall obtain the value of the process-shared attribute  from
       the initialized attributes object referenced by attr.  The pthread_rwlockattr_setpshared() function shall
       set the process-shared attribute in an initialized attributes object referenced by attr.

       The process-shared attribute shall be set to PTHREAD_PROCESS_SHARED to permit a  read-write  lock  to  be
       operated upon by any thread that has access to the memory where the read-write lock is allocated, even if
       the read-write lock is allocated in memory that is shared by multiple processes.  If  the  process-shared
       attribute  is PTHREAD_PROCESS_PRIVATE, the read-write lock shall only be operated upon by threads created
       within the same process as the thread that initialized the  read-write  lock;  if  threads  of  differing
       processes  attempt  to operate on such a read-write lock, the behavior is undefined. The default value of
       the process-shared attribute shall be PTHREAD_PROCESS_PRIVATE.

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

       The  behavior is undefined if the value specified by the attr argument to pthread_rwlockattr_getpshared()
       or pthread_rwlockattr_setpshared() does not refer to an initialized read-write lock attributes object.


RETURN VALUE
       Upon successful completion, the pthread_rwlockattr_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_rwlockattr_setpshared() function shall return zero; otherwise, an error number
       shall be returned to indicate the error.


ERRORS
       The pthread_rwlockattr_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
       None.


FUTURE DIRECTIONS
       None.


SEE ALSO
       pthread_rwlock_destroy(), pthread_rwlockattr_destroy()

       The Base Definitions volume of POSIX.1‐2008, <pthread.h>


       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2013 Edition,
       Standard for Information Technology -- 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 Standard 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 .