pthread_cond_broadcast - Wakes all threads that are waiting on the specified condition variable.
DECthreads POSIX 1003.1c Library (libpthread.so)
Interfaces documented on this reference page conform to industry standards as follows:
IEEE Std 1003.1c-1995, POSIX System Application Program Interface
Condition variable upon which the threads (to be awakened) are waiting.
This routine unblocks all threads waiting on the specified condition variable cond. Calling this routine implies that data guarded by the associated mutex has changed, so that it might be possible for one or more waiting threads to proceed. The threads that are unblocked shall contend for the mutex according to their respective scheduling policies (if applicable).
If only one of the threads waiting on a condition variable may be able to proceed, but any single thread can proceed, then use pthread_cond_signal(3) instead.
Whether the associated mutex is locked or unlocked, you can still call this routine. However, if predictable scheduling behavior is required, that mutex should then be locked by the thread calling the pthread_cond_broadcast(3) routine.
If no threads are waiting on the specified condition variable, this routine takes no action. The broadcast does not propagate to the next condition variable wait.
If an error condition occurs, this routine returns an integer value indicating the type of error. Possible return values are as follows: Successful completion. The value specified by cond is invalid.
Functions: pthread_cond_destroy(3), pthread_cond_init(3), pthread_cond_signal(3), pthread_cond_timedwait(3), pthread_cond_wait(3)
Manuals: Guide to DECthreads and Programmer's Guide