Int 13 Fn FA - PC Tools V8+ Vsafe, Vwatch - API [v] AH = FAh DX = 5945h AL = function (00h-07h) Return: varies by function if not installed: CF set AH = 01h Note: this API is identical to the ones on INT 16/AH=FAh and INT 21/AH=FAh, so it is listed in its entirety under INT 16/AX=FA00h and following See Also: INT 16/AX=FA00h