pthread_cond_signal(3C) 				   Standard C Library Functions 				   pthread_cond_signal(3C)

NAME

       pthread_cond_signal, pthread_cond_broadcast - signal or broadcast a condition

SYNOPSIS

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

       int pthread_cond_signal(pthread_cond_t *cond);

       int pthread_cond_broadcast(pthread_cond_t *cond);

DESCRIPTION

       These two functions are used to unblock threads blocked on a condition variable.

       The  pthread_cond_signal()  call  unblocks  at  least  one of the threads that are blocked on the specified condition variable cond (if any
       threads are blocked on cond).

       The pthread_cond_broadcast() call unblocks all threads currently blocked on the specified condition variable cond.

       If more than one thread is blocked on a condition variable, the scheduling policy determines the order in which threads are unblocked. When
       each  thread  unblocked	as a result of a pthread_cond_signal() or pthread_cond_broadcast() returns from its call to pthread_cond_wait() or
       pthread_cond_timedwait(), the thread owns the mutex with which it called pthread_cond_wait()  or  pthread_cond_timedwait().  The  thread(s)
       that   are   unblocked  contend	for  the  mutex  according  to	the  scheduling  policy  (if  applicable),  and  as  if  each  had  called
       pthread_mutex_lock().

       The pthread_cond_signal() or pthread_cond_broadcast() functions may be called by a thread whether or not it currently owns the  mutex  that
       threads calling pthread_cond_wait() or pthread_cond_timedwait() have associated with the condition variable during their waits; however, if
       predictable scheduling behavior is required, then that mutex is locked by the thread calling pthread_cond_signal()  or  pthread_cond_broad-
       cast().

       The pthread_cond_signal() and pthread_cond_broadcast() functions have no effect if there are no threads currently blocked on cond.

RETURN VALUES

       If  successful, the pthread_cond_signal() and pthread_cond_broadcast() functions return	0. Otherwise, an error number is returned to indi-
       cate the error.

ERRORS

       The  pthread_cond_signal() and pthread_cond_broadcast() function may fail if:

       EINVAL	 The value cond does not refer to an initialized condition variable.

ATTRIBUTES

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

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Standard			   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |MT-Safe			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       pthread_cond_init(3C), pthread_cond_wait(3C), pthread_cond_timedwait(3C), attributes(5), condition(5), standards(5)

SunOS 5.11							    23 Mar 2005 					   pthread_cond_signal(3C)