pthread_spin_trylock(3p) - phpMan

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

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_spin_lock, pthread_spin_trylock  -  lock  a  spin  lock  object
       (ADVANCED REALTIME THREADS)
SYNOPSIS
       #include <pthread.h>
       int pthread_spin_lock(pthread_spinlock_t *lock);
       int pthread_spin_trylock(pthread_spinlock_t *lock);

DESCRIPTION
       The pthread_spin_lock() function shall lock the spin lock referenced by
       lock. The calling thread shall acquire the lock if it is  not  held  by
       another  thread.  Otherwise,  the thread shall spin (that is, shall not
       return from the pthread_spin_lock() call) until the lock becomes avail-
       able.   The  results are undefined if the calling thread holds the lock
       at the time the call is made. The pthread_spin_trylock() function shall
       lock  the spin lock referenced by lock if it is not held by any thread.
       Otherwise, the function shall fail.
       The results are undefined if any of these functions is called  with  an
       uninitialized spin lock.
RETURN VALUE
       Upon  successful  completion, these functions shall return zero; other-
       wise, an error number shall be returned to indicate the error.
ERRORS
       These functions may fail if:
       EINVAL The value specified by lock does not  refer  to  an  initialized
              spin lock object.

       The pthread_spin_lock() function may fail if:
       EDEADLK
              The calling thread already holds the lock.

       The pthread_spin_trylock() function shall fail if:
       EBUSY  A thread currently holds the lock.

       These functions shall not return an error code of [EINTR].
       The following sections are informative.
EXAMPLES
       None.
APPLICATION USAGE
       Applications  using this function may be subject to priority inversion,
       as discussed in the Base Definitions  volume  of  IEEE Std 1003.1-2001,
       Section 3.285, Priority Inversion.
       The  pthread_spin_lock()  and pthread_spin_trylock() functions are part
       of the Spin Locks option and need not be provided  on  all  implementa-
       tions.
RATIONALE
       None.
FUTURE DIRECTIONS
       None.
SEE ALSO
       pthread_spin_destroy(),  pthread_spin_unlock(),  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_LOCK(3P)