Int 2F Fn F100 - DOS Extender Installation Check [E] AX = F100h Return: AL = FFh if DOS extender present SI = 444Fh ("DO") DI = 5358h ("SX") Note: supported or soon to be supported by Phar Lap, Rational, Ergo, and IGC See Also: AH=A1h,AX=ED00h,AX=FBA1h/BX=0081h,INT 15/AX=BF02h