5. The Telnet Subsystem

   The Telnet subsystem coding should fit easily into one core page, for
   it does very little.  It effectively establishes a shunt in the user
   HOST between the remote user and the serving HOST.  Telnet commands
   are:

   ESCAPE CHAR IS ___________<CR>      Declares a character which
                                       Telnet will watch for.
                                       Subsequent strings typed
                                       between this character and
                                       a carriage return are not
                                       shunted through to the serving
                                       host, but sent instead to the
                                       Telnet program in the user's
                                       local HOST.

   This escape character is not the same as the user's host
   rubout character.

   CONNECT TO __________________<CR>   The official site name of the
                                       desired serving HOST is typed
                                       (i.e.: SRI, UTAH, UCLA, UCSB).
                                       Telnet attempts to establish a
                                       connection.  If the attempt is
                                       successful, the following
                                       characters are shunted through
                                       the user's local machine.  The
                                       connection places the user in
                                       the pre-logged in state at
                                       the serving HOST.

   LOGOUT<CR>                          Telnet issues the logout command
                                       sequence to the serving HOST.
                                       If the user simply rubs out and
                                       kills his PDP-10 job, the
                                       PDP-10 will indicate to the 940
                                       that the connection is closed.
                                       The 940 system primitives do
                                       whatever they do when a normal
                                       dataphone connection is
                                       suddenly broken.

   COPY FILE                           A file copying command is
                                       available in TELNET to
                                       move data along on auxiliary
                                       connections from the
                                       user's HOST file system
                                       to the serving HOST.
        On the 940 this is:

   COPY <file name> TO NETWRK.
   -                   -     -

        On the PDP-10:

   NETWRK <- DSK: <file name>
   --------------------------

   These TELNET commands are accepted when the TELNET subsystem is first
   entered or following the declared escape character.