al_unlock_mutex - Allegro 5 API

       Release the lock on mutex if the calling thread holds the lock on it.

       If the calling thread doesn’t hold the lock, or if the mutex is not locked, undefined behaviour results.

       al_unlock_mutex - Allegro 5 API

al_lock_mutex(3alleg5).

Allegro reference manual                                                                al_unlock_mutex(3alleg5)

              #include <allegro5/allegro.h>

              void al_unlock_mutex(ALLEGRO_MUTEX *mutex)