CADR Chaosnet README
brad@heeltoe.com
07/11/06

Chaosnet simulator for CADR simulator

Updates
-------

07/11/06 fixed FILE server to force everything to lower case
         (still a bug in close - don't open multiple files)
         some macos fixes, doesnt' work yet in big endian
	 works well enough to support (si:recompile-world)

12/13/05 original release

What the heck is this?
----------------------

Chaosnet was an early (pre-ethernet) computer network developed at
MIT.  It was an early "common bus" packet network, i.e. all the
machines shared a single "wire" and sent packets back and forth.

Chaosnet was used to connect many machines at MIT, most notably the
PDP-10's running ITS and the lisp machines.  

This code simulates a chaosnet network on a single machine.  There is
a central server which clients connect to using unix sockets.  The
server relays packets back and forth between the clients.

The CADR simulator (usim) can be a client and uses this code to talk
to the FILE server ("FILE" is the file serving protocol used on
chaosnet).

How do I use it?
----------------

The simple case is to run "chaosd" in a directory which has "server"
and "FILE" in it.  chaosd will exec server in the background and
server will exec FILE when a connection is made.  So just type
"./chaosd" in the source directory.

The servers are designed to run in the background and can be made to
do so with command line argument.  I have not tested this fully,
however and it could easily be the case that the the exec will fail
because the programs can not be found.

Once chaosd is running you can start up usim and it will connect.  You
can watch the packet flow by running "listen".

usim will automatically reconnect to the server if the server is
killed or dies.  In theory you can start usim first.

Quick Start
-----------

	run chaosd in one window
	run usim in another
	wait for the lispm to ask you for the date & time
	type

	  (si:set-sys-host "server" ':unix 404)
	  (load "server://path-to-file//tv.lisp")
	  (tv:set-tv-lines 640.)

	This will change the screen to be 640 lines.

What's the point?
-----------------

If you run chaosd and then usim, you can get the CADR to talk to the file
server and read files from your linux host.

Once the CADR is running type this

	(si:set-sys-host "server" ':unix 404 "//tmp")

Note this command will take a little while to complete.

Then get into zwei (emacs) with F2-e and type ^X^F (find file) and
then type "server:/path/to/a/text/file".  The file will appear in the
emacs buffer.  Viola.  It's not fast but it works.

At this point the system is stable enough that it can recompile the
entire source tree.  I hope to make a cold load band soon.


Chaosnet addressing
-------------------

in octal

0401	usim
0404	server

The code currently assumes a single usim running with chaos address
(octal) 401.  The server runs at address (octal) 404.


Utilities
---------
chaosd - router daemon
server - chaosnet server
FILE - port of FILE server
listen - packet dumper
client - simple test client