al_get_joystick_guid(3)    Library Functions Manual    al_get_joystick_guid(3)

NAME
       al_get_joystick_guid - Allegro 5 API

SYNOPSIS
              #include <allegro5/allegro.h>

              ALLEGRO_JOYSTICK_GUID al_get_joystick_guid(ALLEGRO_JOYSTICK *joy)

DESCRIPTION
       Returns the joystick GUID, that can be used to distinguish joysticks
       hardware.  Despite the name, these do not need to be actually unique to
       do the limitations of the system that computes them.  This can be all
       zeros when unknown.

SINCE
       5.2.11

SEE ALSO
       ALLEGRO_JOYSTICK_GUID(3)

              [Unstable API]: New API.

Allegro reference manual                               al_get_joystick_guid(3)