al_get_event_source_data - Man Page

#include <allegro5/allegro.h>

intptr_t al_get_event_source_data(const ALLEGRO_EVENT_SOURCE *source)

Returns the abstract user data associated with the event source. If no data was previously set, returns NULL.

al_set_event_source_data(3)

al_set_event_source_data(3).