al_install_haptic man page
al_install_haptic — Allegro 5 API
#include <allegro5/allegro.h> bool al_install_haptic(void)
Installs the haptic (force feedback) device subsystem. This must be called before using any other haptic-related functions. Returns true if the haptics subsystem could be initialized correctly, false in case of error.
For portability you should first open a display before calling al_install_haptic(3). On some platforms, such as DirectInput under Windows, al_install_haptic(3) will only work if at least one active display is available. This display must stay available until al_uninstall_haptic(3) is called.
If you need to close and reopen your active display for example, then you should call al_uninstall_haptic(3) before closing the display, and al_install_haptic(3) after opening it again.
[Unstable API]: Perhaps could be simplified due to limited support for all the exposed features across all of the platforms. Awaiting feedback from users.