Int 2A Fn FF92  - PC/tcp Predir.exe - Installation Check                   [N]

   AX = FF92h

Return: AX = 0000h if installed
      BX = redirected printer port (FFFFh if no printers redirected)
      CX = version (CH = major, CL = minor)

Note:  PREDIR.EXE is the network printer redirector included as part of the
     PC/TCP system by FTP Software, Inc.