Defined in header
Atomically unlocks the mutex pointed to by
mutex and blocks on the condition variable pointed to by
cond until the thread is signalled by cnd_signal or cnd_broadcast. The mutex is locked again before the function returns.
The behavior is undefined if the mutex is not already locked by the calling thread.
|cond||-||pointer to the condition variable to block on|
|mutex||-||pointer to the mutex to unlock for the duration of the block|