int
     pthread_mutex_trylock(pthread_mutex_t *mutex);

DESCRIPTION

     The pthread_mutex_trylock() function locks mutex.  If the mutex is
     already locked, pthread_mutex_trylock() will not block waiting for the
     mutex, but will return an error condition.

RETURN VALUES

     If successful, pthread_mutex_trylock() will return zero, otherwise an
     error number will be returned to indicate the error.

ERRORS

     pthread_mutex_trylock() will fail if:

     [EINVAL]           The value specified by mutex is invalid.

     [EBUSY]            Mutex is already locked.

SEE ALSO

     pthread_mutex_destroy(3), pthread_mutex_init(3), pthread_mutex_lock(3),
     pthread_mutex_unlock(3)

STANDARDS

     pthread_mutex_trylock() conforms to ISO/IEC 9945-1:1996 (``POSIX.1'').

BSD                              July 30, 1998                             BSD