al_create_file_handle - Allegro 5 API

       Creates  an  empty,  opened  file  handle with some abstract user data.  This allows custom interfaces to
       extend the ALLEGRO_FILE(3alleg5) struct with their own data.   You  should  close  the  handle  with  the
       standard al_fclose(3alleg5) function when you are finished with it.

       al_create_file_handle - Allegro 5 API

al_fopen(3alleg5), al_fclose(3alleg5), al_set_new_file_interface(3alleg5)

Allegro reference manual                                                          al_create_file_handle(3alleg5)

              #include <allegro5/allegro.h>

              ALLEGRO_FILE *al_create_file_handle(const ALLEGRO_FILE_INTERFACE *drv,
                 void *userdata)