Int 7F Fn 26  - Alloy Ntnx - Set File I/o Checking Level                   [N]

   AH = 26h
   CL = check type to set/reset
       01h directory protection
       02h extended open
       03h flush on every disk write
       04h flush on disk write if any lock set during write
       05h flush on all reads if file written
   AL = new state (00h off, 01h on)

See Also: AH=26h/CL=00h,AH=26h/CL=06h