PTHREAD_RWLOCKATTR_GETPSHAREPDO(S3I)X Programmer's MPaTnHuRaElAD_RWLOCKATTR_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_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. See Section 2.9.9, Synchronization Object Copies and
       Alternative Mappings for further requirements. 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.1-2017, <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_RWLOCKATTR_GETPSHARED(3)
