al_popup_menu - Allegro 5 API

       Displays   a   context   menu  next  to  the  mouse  cursor.   The  menu  must  have  been  created  with
       al_create_popup_menu(3alleg5).  It generates events just  like  a  regular  display  menu  does.   It  is
       possible that the menu will be canceled without any selection being made.

       The display parameter indicates which window the menu is associated with (when you process the menu click
       event), but does not actually affect where the menu is located on the screen.

       Returns true if the context menu was displayed.

              Note: On Linux this function will fail if any of the mouse keys are held down.  I.e.  it will only
              reliably  work if you handle it in ALLEGRO_MOUSE_BUTTON_UP events and even then only if that event
              corresponds to the final mouse button that was pressed.

       al_popup_menu - Allegro 5 API

al_create_popup_menu(3alleg5)

Allegro reference manual                                                                  al_popup_menu(3alleg5)

       5.1.0

              #include <allegro5/allegro_native_dialog.h>

              bool al_popup_menu(ALLEGRO_MENU *popup, ALLEGRO_DISPLAY *display)