pthread_mutex_timedlock(3C)				   Standard C Library Functions 			       pthread_mutex_timedlock(3C)

NAME

       pthread_mutex_timedlock, pthread_mutex_reltimedlock_np - lock a mutex

SYNOPSIS

       cc -mt [ flag... ] file... [ library... ]
       #include <pthread.h>
       #include <time.h>

       int pthread_mutex_timedlock(pthread_mutex_t *restrict mutex, const struct timespec *restrict abs_timeout);

       int pthread_mutex_reltimedlock_np(pthread_mutex_t *restrict mutex, const struct timespec *restrict rel_timeout);

DESCRIPTION

       The  pthread_mutex_timedlock()  function  locks	the  mutex  object referenced by mutex. If the mutex is already locked, the calling thread
       blocks until the mutex becomes available as in the pthread_mutex_lock(3C). If the mutex cannot be locked without waiting for another thread
       to unlock the mutex, this wait is terminated when the specified timeout expires.

       The  pthread_mutex_reltimedlock_np()  function is identical to the pthread_mutex_timedlock() function, except that the timeout is specified
       as a relative time interval.

       For pthread_mutex_timedlock(), the timeout expires when the absolute time specified by abs_timeout passes, as  measured	by  the  clock	on
       which  timeouts	are  based  (that  is,	when  the value of that clock equals or exceeds abs_timeout), or if the absolute time specified by
       abs_timeout has already been passed at the time of the call.

       For pthread_mutex_reltimedlock_np(), the timeout expires when the time interval	specified  by  rel_timeout  passes,  as  measured  by  the
       CLOCK_REALTIME clock, or if the time interval specified by rel_timeout is negative at the time of the call.

       The resolution of the timeout is the resolution of the CLOCK_REALTIME clock. The timespec data type is defined in the <time.h> header.

       Under  no circumstance will either function fail with a timeout if the mutex can be locked immediately. The validity of the timeout parame-
       ter need not be checked if the mutex can be locked immediately.

       As a consequence of the priority inheritance rules (for mutexes initialized with the PRIO_INHERIT protocol), if a timed mutex wait is  ter-
       minated	because  its timeout expires, the priority of the owner of the mutex is adjusted as necessary to reflect the fact that this thread
       is no longer among the threads waiting for the mutex.

RETURN VALUES

       Upon successful completion, the pthread_mutex_timedlock() and pthread_mutex_reltimedlock_np() functions return 0. Otherwise, an error  num-
       ber is returned to indicate the error.

ERRORS

       The pthread_mutex_timedlock() and pthread_mutex_reltimedlock_np() functions will fail if:

       EINVAL	       The  mutex  was created with the protocol attribute having the value PTHREAD_PRIO_PROTECT and the calling thread's priority
		       is higher than the mutex's current priority ceiling.

       EINVAL	       The process or thread would have blocked and the timeout parameter specified a nanoseconds field value less  than  zero	or
		       greater than or equal to 1,000 million.

       ETIMEDOUT       The mutex could not be locked before the specified timeout expired.

       The pthread_mutex_timedlock() and pthread_mutex_reltimedlock_np() functions may fail if:

       EINVAL	       The value specified by mutex does not refer to an initialized mutex object.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |See below.		   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |MT-Safe			   |
       +-----------------------------+-----------------------------+

       The pthread_mutex_timedlock() is Standard. The pthread_mutex_reltimedlock_np() function is Stable.

SEE ALSO

       time(2), pthread_mutex_destroy(3C), pthread_mutex_lock(3C), pthread_mutex_trylock(3C), attributes(5), standards(5)

SunOS 5.10							    30 Jan 2004 				       pthread_mutex_timedlock(3C)