Wakes up all the threads blocked on the condition variable.
#include <pthread.h>
int pthread_cond_broadcast (
pthread_cond_t *cond);
(IN) Points to the condition variable to signal.
If successful, returns 0. Otherwise returns a nonzero error code.
Condition variables are stateless. Calling pthread_cond_broadcast on a condition variable that does not have any waiting threads has no effect and is not remembered; a subsequent call to pthread_cond_wait or pthread_cond_timedwait will block the calling thread.