al_set_display_menu - Allegro 5 API

       Associates  the  menu  with  the  display and shows it.  If there was a previous menu associated with the
       display, it will be destroyed.  If you don’t want that to happen, you should first remove the  menu  with
       al_remove_display_menu(3alleg5).

       If  the  menu  is  already attached to a display, it will not be attached to the new display.  If menu is
       NULL, the current menu will still be destroyed.

              Note: Attaching a menu may cause the window as available to your application to be  resized!   You
              should listen for a resize event, check how much space was lost, and resize the window accordingly
              if you want to maintain your window’s prior size.

       Returns true if successful.

       al_set_display_menu - Allegro 5 API

al_create_menu(3alleg5), al_remove_display_menu(3alleg5)

Allegro reference manual                                                            al_set_display_menu(3alleg5)

       5.1.0

              #include <allegro5/allegro_native_dialog.h>

              bool al_set_display_menu(ALLEGRO_DISPLAY *display, ALLEGRO_MENU *menu)