INT 2fH ae01H: Process Hooked Command

                                                 Compatibility: ◄Undoc► 3.0+ 
 Expects: AX    ae01H
          DS:SI address of an 8-byte upshifted, blank-padded command name
                (save command-line text addr from previous INT 2fH ae00H)
 Returns:       Previously-passed command buffer should be modified:
                Set the length field to 00H to indicate command completed.
    Info: This is part two of a system that lets TSRs intercept commands
          typed at the DOS command prompt.

          See INT 2fH ae00H for details on what happens in part one.  After
          you return AL=ffH from that notification, COMMAND.COM immediately
          calls this function (AX=ae01H) to give you a crack at processing
          the command.

          Important: This command does not supply the full command-line
          text.  You must save the DS:BX value passed in the previous
          AX=ae00H notification.

          █▌Handling a Command Internally▐█
          Examine the command line text (as pointed to by the DS:BX
          obtained in the earlier ae00H call).  Take whatever action you
          deem necessary.  Set the command length to 0 (DS:BX+1) and IRET
          to return control to COMMAND.COM.

          █▌Cancelling a Command▐█
          Just set the saved DS:[BX+1] to 00H and IRET to return control to

          █▌Pre-processing a Command▐█
          It is possible to examine command-line switches and options, make
          some changes, and then pass the result on to be handled by
          COMMAND.COM or some other INT 2fH handler.  In this case, use a
          FAR JMP to pass control down the chain of INT 2fH handlers, to
          give them a crack at the command.  In any case, if the command-
          line length is non-zero, it will be processed eventually --
          either by another INT 2fH handler or by COMMAND.COM.

   Notes: ■ If Doskey is installed (see INT 2fH 4800H), then Doskey will
            get a crack at the command-line before you do.  You might
            consider chaining into that service as well.

          ■ Note that batch file commands are passed through this system,
            so you can make a bullet-proof connad filter.

See Also: INT 2fH aexxH Command Processor Hook
          INT 2fH: Multiplex Interrupt
          DOS Functions