INT 21 - DOS 3.0+ - IOCTL - CHECK IF BLOCK DEVICE REMOVABLE AX = 4408h BL = drive number (00h = default, 01h = A:, etc) Return: CF clear if successful AX = 0000h if removable = 0001h if fixed CF set on error AX = error code (01h,0Fh) (see AH=59h) SeeAlso: AX=4409h,INT 2F/AX=122Bh