al_wait_for_event_until - Allegro 5 API

       Wait  until  the  event  queue  specified is non-empty.  If ret_event is not NULL, the first event in the
       queue will be copied into ret_event and removed from the queue.  If ret_event is NULL the first event  is
       left at the head of the queue.

       timeout  determines  how long to wait.  If the call times out, false is returned.  Otherwise, if an event
       ocurred, true is returned.

       For compatibility with all platforms, timeout must be 2,147,483.647 seconds or less.

       al_wait_for_event_until - Allegro 5 API

ALLEGRO_EVENT(3alleg5), ALLEGRO_TIMEOUT(3alleg5),  al_init_timeout(3alleg5),  al_wait_for_event(3alleg5),
       al_wait_for_event_timed(3alleg5)

Allegro reference manual                                                        al_wait_for_event_until(3alleg5)

              #include <allegro5/allegro.h>

              bool al_wait_for_event_until(ALLEGRO_EVENT_QUEUE *queue,
                 ALLEGRO_EVENT *ret_event, ALLEGRO_TIMEOUT *timeout)