PTHREAD_SPIN_UNLOCK(P)     POSIX Programmer's Manual    PTHREAD_SPIN_UNLOCK(P)



NAME
       pthread_spin_unlock  -  unlock  a  spin  lock object (ADVANCED REALTIME
       THREADS)

SYNOPSIS
       #include <pthread.h>

       int pthread_spin_unlock(pthread_spinlock_t *lock);


DESCRIPTION
       The pthread_spin_unlock() function shall release the spin  lock  refer-
       enced   by  lock  which  was  locked  via  the  pthread_spin_lock()  or
       pthread_spin_trylock() functions. The results are undefined if the lock
       is not held by the calling thread. If there are threads spinning on the
       lock when pthread_spin_unlock() is called, the lock  becomes  available
       and an unspecified spinning thread shall acquire the lock.

       The results are undefined if this function is called with an uninitial-
       ized thread spin lock.

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

ERRORS
       The pthread_spin_unlock() function may fail if:

       EINVAL An invalid argument was specified.

       EPERM  The calling thread does not hold the lock.


       This function shall not return an error code of [EINTR].

       The following sections are informative.

EXAMPLES
       None.

APPLICATION USAGE
       The pthread_spin_unlock() function is part of the Spin Locks option and
       need not be provided on all implementations.

RATIONALE
       None.

FUTURE DIRECTIONS
       None.

SEE ALSO
       pthread_spin_destroy()  ,  pthread_spin_lock()  ,  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_SPIN_UNLOCK(P)