Eek...!
I think you're not supposed to touch that function.... 'course could be something like: "Microsoft recommends that you no longer use DOS functions 01h to 0dh, unless needed to maintain older code. Microsoft cannot garantee that these functions will still exist in future versions of DOS." which never really stopped us from using them, did they? "Information has a tendency to be free. Which means someone will always tell you something you don't want to know."