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	The uutty package is John Chambers' very own person login
	daemon, to replace such things as getty(1) and login(1).
	
	There are several motives for doing this.  You might have
	a modem which you wish to use for both incoming and outgoing
	calls.  You might have a direct ("null modem") link which
	you would like to use from either end.  You might have an
	overly-intelligent modem which is crashing your system by
	engaging getty in a conversation.  All of these can be
	handled by uutty.  
	
	Also, uutty will make an audit trail for you in the file
	of your choice.  Note:  at debug level -d2 and above,
	uutty is a "Trojan horse", since the audit trail will
	contain unencrypted login ids and passwords.  This is
	very useful on occasion; it is also an extreme security
	risk.  Think carefully before you try this on a regular
	basis.
	
	To create the program, first edit the *.h files and the
	Makefile.  There isn't much that needs to be changed,
	but you probably want to modify the -DSYS5 and -DCadmus
	parameters to specify your variety of Unix and your 
	manufacturer's name.  You might also try:
		grep SYS5 *.c
		grep Cadmus *.c
	and check out all these pieces of code to see if they
	look correct for your system.
	
	If you make any interesting changes to port it to your
	system, you might share them with the author:
		...!cdx39!jc (John Chambers)
	This will help towards producing a truly portable version
	of this logger.
	
	When you've convinced yourself that the system dependencies
	are OK, just type "make", and uutty will be compiled.  To
	install it and the manual entry , type "install"; you'll 
	have to be a super-user to do this.
	
	To run it, you need to explain to init about it.  Here 
	are some typical entries from our /etc/inittab file:

t11:23 :respawn:modem /dev/tty11 -B12				# Modem for uucp.
t30:234:respawn:uutty /dev/tty30 -B96 -e 2>>/user/aud/tty30	# Ordinary terminal port.
t40:34:off    : uutty /dev/tty40 -B96 2>>/user/aud/tty40 -l -d2	# Direct link.
t41:34:respawn: uutty /dev/tty41 -B96 2>>/user/aud/tty41 -l -d2	# Direct link.
t42:34:respawn: uutty /dev/tty42 -B96 2>>/user/aud/tty42 -l -d2	# Direct link.
t43:34:respawn: uutty /dev/tty43 -B96 2>>/user/aud/tty43 -l -d2	# Direct link.

	What we are doing here is using uutty on four inter-machine
	direct links (null-modem or cross-over cables), on the
	tty4? ports.  The tty30 port is attached to a terminal
	(well, actually to our LAN); uutty is being run there
	just to show that it works with the -e option.  The tty11 
	port is attached to an overly-intelligent ACU-type modem.  
	The 'modem' program is a shell script, which looks like:
	
>	:
>	MODEM=tty11
>	/usr/lib/uucp/modem_init $1
>	cd /etc
>	PATH=.:$PATH
>	exec uutty /dev/$MODEM -B12 -L -d2 -i\\rqOG0\\rXXXT\\rqOG0 2>>/user/aud/$MODEM 
>	:
>	: We normally won't reach this:
>	sleep 30
>	/usr/lib/uucp/modem_init $1
	
	The purpose of this is to run a special script, modem_init,
	to beat on the modem and try to put it into a quiescent state.
	When this is done, we run uutty at 1200 baud, with locking
	enabled, at debug level 2 (tracing of all input and output),
	and with a bizarre-looking initialization string which turns
	out to be what this particular modem requires to force it to
	hang up and re-initialize itself.  The final sleep and call
	on modem_init are to handle cases where init somehow can't
	find uutty, or it dies instantaneously.  This may look like
	overkill; it turns out to have been useful on occasion.
	
	Note that the audit trail grows without bound.  Once a day,
	we handle it by having cron start up /etc/cleanup, a script
	that moves a select list of files to a backup copy.  This
	generally suffices to keep the audit trail to a reasonable
	size.
	
	When you first run uutty, you should probably try it with
	-d5 or -d8, to have it explain what it's doing.  It will
	likely get into a conversation with your modem; you'll
	have to figure out if there's a possible initialization
	string that will prevent it.  Hint:  Try to tell your
	modem not to echo anything.
	
	A more useful first test is to run uutty on one end of
	a null-modem cable, which could be to another computer,
	or to two ports on the same computer.  Use cu(1) to
	connect to it, and have either getty or uutty running
	on the other end.  After at most two RETURNs, you should
	get a login prompt, and uutty's audit trail should show
	that there is a lockfile.  When you tell cu to disconnect,
	the lockfile will go away, and uutty will wake up in
	half a minute or so.  If you are still logged in at 
	the other end, uutty may discover this, and log you
	out; on the other hand, it may not.  (It's supposed
	to, if you have a Unix prompt ending with '$' or '%'.)
	
	Enjoy!
	
	John M Chambers 
Phone: 617/364-2000x7304
Email: ...{cthulhu,inmet,harvax,mit-eddie,mot[bos],rclex}!cdx39!{jc,news,root,usenet,uucp}
Smail: Codex Corporation; Mailstop C1-30; 20 Cabot Blvd; Mansfield MA 02048-1193
Telex: 922-443 CODEX A MNSF
DataMuseum.dk

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