pthread_cond_wait(3) [freebsd man page]

PTHREAD_COND_WAIT(3)					   BSD Library Functions Manual 				      PTHREAD_COND_WAIT(3)

NAME

     pthread_cond_wait -- wait on a condition variable

LIBRARY

     POSIX Threads Library (libpthread, -lpthread)

SYNOPSIS

     #include <pthread.h>

     int
     pthread_cond_wait(pthread_cond_t *cond, pthread_mutex_t *mutex);

DESCRIPTION

     The pthread_cond_wait() function atomically blocks the current thread waiting on the condition variable specified by cond, and releases the
     mutex specified by mutex.	The waiting thread unblocks only after another thread calls pthread_cond_signal(3), or pthread_cond_broadcast(3)
     with the same condition variable, and the current thread reacquires the lock on mutex.

RETURN VALUES

     If successful, the pthread_cond_wait() function will return zero.	Otherwise an error number will be returned to indicate the error.

ERRORS

     The pthread_cond_wait() function will fail if:

     [EINVAL]		The value specified by cond or the value specified by mutex is invalid.

     [EPERM]		The specified mutex was not locked by the calling thread.

SEE ALSO

     pthread_cond_broadcast(3), pthread_cond_destroy(3), pthread_cond_init(3), pthread_cond_signal(3), pthread_cond_timedwait(3)

STANDARDS

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

BSD
								 February 16, 2006							       BSD

pthread_cond_signal(3C) 												   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);

       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.

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

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

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

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

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

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

								    23 Mar 2005 					   pthread_cond_signal(3C)