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