cond
Condition variable that the calling thread waits on.
mutex
Mutex associated with the condition variable specified in cond.
abstime
Absolute time at which the wait expires, if the condition has not
been signaled or broadcast. See the pthread_get_expiration_np()
routine, which is used to obtain a value for this argument.
The abstime argument is specified in Universal Coordinated Time
(UTC). In the UTC-based model, time is represented as seconds
since the Epoch. The Epoch is defined as the time 0 hours, 0
minutes, 0 seconds, January 1st, 1970 UTC.