Allegro 5 api
#include <allegro5/allegro.h> bool al_wait_for_event_until(ALLEGRO_EVENT_QUEUE *queue, ALLEGRO_EVENT *ret_event, ALLEGRO_TIMEOUT *timeout)
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 true is returned.
ALLEGRO_EVENT(3alleg5), ALLEGRO_TIMEOUT(3alleg5), al_init_timeout(3alleg5), al_wait_for_event(3alleg5), al_wait_for_event_timed(3alleg5)