HFC live on 3.51

[was-John McMillan]

I spoken with Dave & may have solved his problems.  Alas, on my machines:
	1)  I rarely use the User Agent[UA];
	2)  I'm running HDB, and it overrides the UA in RS232-controls.
Ergo: while I may be able to help others with Flow Control problems, it
can't be through UA-based interaction.

Flow Control is handled by "/etc/hfc_ctl":
    /etc/hfc_ctl  +/dev/tty000	-- ENables HFC on built-in port.
    /etc/hfc_ctl  +/dev/tty003	-- ENables HFC on 2nd Combo-bd, 1st port.

    /etc/hfc_ctl  -/dev/tty002	-- DISables HFC on 1st Combo-bd, 2nd port.

It can be executed on a running system while one is ROOT.  (It MAY even be
effective if one isn't ROOT...  I'm away from the sources.)  'Wouldn't
recommend pointing it at an open, active line however!

It is USUALLY executed during BOOT from an executable script file in
"/etc/daemons":
   /etc/daemons/tty000.init:	/etc/hfc_ctl  -/dev/tty000
   /etc/daemons/tty001.init:	/etc/hfc_ctl  +/dev/tty001
   /etc/daemons/tty002.init:	/etc/hfc_ctl  -/dev/tty002

At one time there were some folks running a loadable device-driver:
/etc/lddrv/hfc.o (I believe).  Gods save you if you're running this --
hopefully-undistributed-if-it's-what-I-think -- program on any "recent"
kernel.  I doubt anyone has it, however.
			- - - - - - - - -
Anyone successfully running HFC through the UA might fill in the
details for successfully admin'ing this.

jc mcmillan	-- att!mtunb!jcm	-- for himself, only...