Subject: Xinu

From: [email-masked] (Douglas Comer)
Date: Wed, 15 Nov 1995 16:43:37 -0500

>> Cool on the Xinu.
 >> I have a old one with Vax as the server, and I assume there are
 >> no newer ones that I can use since it is tuned for the 11.
 >> I would like to check this into the oldunix (PUPS, PDP Unix Preservation
 >> Soc) and I believe it can be freely distributed.  Can you verify this fact?

The source code appears in the textbook and is covered by copyright.
However, it can be distributed and used as long as it's not published in
a competing textbook.

 >> If you give me the OK and say it can be re-disted, I will check it in
 >> so people can use it and it will not be forgotten.  
 >> 
 >> Also, if you have any "dummy" install notes I could check in with it.

The distribution used to include a script that installed it (i.e., by
automatically translating all filenames and then re-compiling the source).
I think that's still in the tar file.  In addition, I've attached a copy of
the README files for version 6 & 7 (there are two files for each version).

If there's anything else I can do, let me know.

Cheers,
Doug
----------------------------------------------------------------------------

Jan 21 16:27 1987  Xinu Version 6 Distribution Tape README Page 1

			   X I N U
			   -------

   Xinu is a layered, process-based operating system.  A detailed
description can be found in the text:

	Comer, Douglas E., Operating System Design: The Xinu
	  Approach, Prentice-Hall, 1984.

   To run the software on this tape, you will need a Digital
Equipment Corp. VAX computer running the Berkeley 4.3BSD UNIX
operating system, and at least one Digital Equipment Corporation
LSI 11/2, LSI 11/03, or LSI 11/23 microcomputer.  The VAX is
used to cross-compile, cross-assemble, and cross-load C programs.
The cross-development software produces a memory image for the
LSI 11, which is then downloaded over an RS232 line to the micro.
Once downloaded, the micro runs independently of the VAX.
   The tape is self-contained.  It contains source programs
for both Xinu and the cross-development system.  The tape can
be read into any directory.  These programs do not need to be
placed in system directories unless you want to do so.
   Only the cross-development software has changed between the
book and this release.  In particular, the downloading software
now handles multiple identical LSI 11s by automatically selecting
a free one and reserving it.  This is desirable for instruction
when a class of students competes for access to a small number of
LSI 11s.  There is a command, lusers, that prints a list of LSI 11s
on reserve, and another command, odtunlock, that releases a user's
reservation.

Installation
------------

   Choose a directory for the Xinu software.  You need not be
in this directory to cross-compile or download programs -- it's
merely the place to store the Xinu software.  Moving the soft-
ware to another directory requires recompilation (i.e., re-
installation).  Choosing /usr/Xinu as the directory will save
time during installation because binary files on the tape are
compiled for that directory.  Throughout this documentation the
directory into which you place Xinu is denoted {Xinu-directory}.

   Make the Xinu directory and read in the tape by typing the
following commands:

	mkdir {Xinu-directory}
	cd {Xinu-directory}
	tar xbf 20 /dev/rmt0	(your 1600 bpi tape device may
				 be named something other than
				 /dev/rmt0)

Once the tape has been read, you must change all source programs
that refer to {Xinu-directory} and recompile the binaries.  A
shell script has been provided to do this for you.  To use it,
move to the installation directory and run Install.  NOTE: YOU

Jan 21 16:27 1987  Xinu Version 6 Distribution Tape README Page 2

MUST BE IN THE INSTALLATION DIRECTORY {Xinu-directory}/install
WHEN YOU EXECUTE THIS SCRIPT OR IT WILL NOT WORK.

	cd {Xinu-directory}/install
	./Install

Connect LSI 11 to The VAX
------- --- -- -- --- ---

   If your LSI 11 does not use 9600 baud or it does not use the
vendor's standard console device address (octal 177560), you must
edit the downloading software in {Xinu-directory}/src/cmd.
Speeds below 4800 baud are not recommended because downloading
becomes intolerable.  Thus, it is usually best to rewire the
LSI 11 to use 9600 baud.  There is an Ethernet downloader included
if you have an LSI11/23 with a DEQNA Ethernet interface.  See the
file {Xinu-directory}/lib/machines for configuring the Ethernet
downloader. (You need to connect a serial line anyway, so we
recommend you start with that).

   Choose a tty line on the VAX and connect it to the LSI 11
console port.  Then modify the UNIX system so that it does not
run a login process (getty) on the tty device.  You need to be
super user to do this.

	su
	...supply super user password when asked...
	ln /dev/{tty-that-you-chose} /dev/LSI.1
	...edit /etc/ttys; turn off getty on LSI tty line...
	kill -1 1
	chmod 0666 /dev/LSI.1
	CONTROL-d (to leave super user mode)

You can connect more LSI 11s to the VAX without changing the
software.  All you need to change is the database found in file
{Xinu-directory}/lib/machines.  The cross-development system
allocates an LSI whenever one is needed. It keeps a lock file
in /tmp/xinu to distinguish ownership, and tries to give you
the LSI 11 you used last if it's idle.  It's possible to
separate users into groups (called "classes" for the obvious
reason), and restrict which machines a particular group can
access.  For example, you can reserve some machines for grad
students by placing them in an access group that includes all
physical machines, and placing undergrads in an access group
that only includes half the physical machines.  If a machine
is in two or more groups, people in those groups compete for
it.

Final Installation
----- ------------

   To complete installation you must recompile source programs
that contain references to the Xinu directory.  Shell scripts
have been provided to do the job.  For details, see file

Jan 21 16:27 1987  Xinu Version 6 Distribution Tape README Page 3

README in the installation directory:

	cd {Xinu-directory}/install
	cat README

Directories
-----------

   When the tape has been read, you will find a directory
structure like this:

1 .				Xinu-directory (usually /usr/Xinu)

  2 /bin			cross-development software

  2 /include			include files

  2 /install			installation shell script

  2 /lib			library files

  2 /man			all manual pages for:
    3 /man1			cross-development commands
    3 /man2			Xinu system commands
    3 /man3			library commands

  2 /src			all source programs:
    3 /cmd			cross-development software
    3 /lib			libraries
    3 /sys			Xinu and configuration:
        5 /con			configuration program
        5 /h			Xinu include files
        5 /sys			Xinu and Makefile

   2 README			This file

Problems or Questions
-------- -- ---------

Reports of errors in the software or documentation are gratefully
accepted.  Please mail all comments and bug reports to:

	DARPA Internet/ CSNet address:
		comer @ cs . purdue . edu
	uucp address:
		{allegra, ihnp4} ! purdue ! dec
	Postal address:
		Department of Computer Science
		Purdue University
		West Lafayette, IN  47907
		(317) 494-6009
----------------------------------------------------------------------------

Jan 17 16:16 1987  Xinu Version 6 Distribution Tape install/README Page 1

Installation Details
------------ -------

This is file {Xinu-directory}/install/README.  It contains
instructions for installing the Xinu software and recompiling
it.  These instructions instructions must be followed:
(a) after the distribution tape has been read in, or
(b) after the Xinu directory has been moved.

**************************************************************
***                     4.2bsd Users                       ***
*** NOTE: if you are still running 4.2bsd, you must remove ***
*** all .o files and libraries before doing anything else. ***
*** To do so, type the following:                          ***
***                                                        ***
***             cd {Xinu-directory}/install                ***
***             ./Install 4.2                              ***
**************************************************************

Installation involves changing references to {Xinu-directory}
in all source files and then recompiling them.

Step 1:	Execute shell script "Install" in this directory
	to climb around the tree and create final versions
	of the source files.

		cd {Xinu-directory}/install
		./Install

Step 2:	Change to the source directory and execute the script
	that rebuilds binaries:

		cd {Xinu-directory}/src
        	Makeall > make.out &

	If you have installed Xinu in other than /usr/Xinu,
	this program takes more than 30 minutes on a VAX 780
	(Hence, we suggest that you run it in background).
	Also be warned that there are numerous programs in
	the cross-development software that produce warning
	messages when recompiled.  You do not need to be
	superuser; only directories under {Xinu-directory}
	are affected. 

Step 3:	Add {Xinu-directory}/bin to your "path" so you can
	execute	commands that are found there:

	C-shell users type:

		set path=( $path {Xinu-directory}/bin )

	Bourne shell users type:

		PATH=$PATH:{Xinu-directory}/bin
		export PATH

Jan 17 16:16 1987  Xinu Version 6 Distribution Tape install/README Page 2

	To make Xinu commands accessible after your next
	login, you must change the path assignment in your
	.profile or .cshrc files.

Step 4:	Try the command "odt" in {Xinu-directory}/bin. It
	connects your keyboard to an LSI 11 console input
	and output from the LSI 11 to your terminal screen:

		odt

	To get the attention of the LSI, type backslash
	followed by null (CONTROL @).  The LSI will stop
	execution and print a prompt ("at" sign).  You
	are now talking to the LSI's "ODT" mode (consult
	the vendor's manual for additional information on
	ODT).  To terminate the odt command, kill the
	process with your normal interrupt character
	(usually CONTROL-C or DELETE).

Step 5: Change to the instllation directory and download
	the test program:

		cd {Xinu-directory}/install
		download -a5 lsi.test
		odt

	It will print "hello world." and stop.  When all
	processes complete, type CONTROL-c to kill the odt
	command.

Step 6:	Pick one of your directories and make sure the
	cross-compiler works.

		cd directory-of-your-choice
		cp {Xinu-directory}/src/sys/sys/test.c .
		cc11 -o test.out test.c
		download -a5 test.out
		odt

	This is the normal sequence for using Xinu.  Be
	sure it works before you change the operating
	system.

Step 7:	You are ready to experiment with Xinu itself.
	Change to the source directory and modify the
	configuration for your LSI 11.

		cd {Xinu-directory}/src/sys/sys
		...edit file "Configuration"...
		make a.out
		download -a4
		odt

Jan 17 16:16 1987  Xinu Version 6 Distribution Tape install/README Page 3

	Note that because recompiling the Xinu sources
	may take considerable time.  It is advisable to
	run make in the background with output (and error
	messages) directed to a file.

	Make will recompile the Xinu sources, rebuild
	file "xinu.o", and rebind library "libx.a".
	However, it leaves the new versions in source
	directory.  Make also compiles file "test.c"
	and binds it with the new library to form file
	"a.out".  When you are satisfied that the new
	version works, run "make install" to copy the new
	version into {Xinu-directory}/lib where command
	cc11 accesses it.

	Other arguments can be used with make.  For details
	see the file "Makefile".  Two that particularly
	useful ones are "everything" that runs several
	scripts designed to test source program formats,
	and "d" that runs "download -a4 ; odt" after remaking
	a.out.  Thus, you normally run "make d" after a
	change to recompile, download, and test the system.

Suggestions
-----------

   Suggestions and reports of problems are welcomed.

----------------------------------------------------------------------------

Jan 14 09:12 1987  Xinu Version 7 Distribution Tape README Page 1

			   X I N U
			   -------

   Xinu is a layered, process-based operating system.  A detailed
description can be found in the text:

	Comer, Douglas E., Operating System Design: The Xinu
	  Approach, Prentice-Hall, 1984.

This directory contains version 7 of the software (including Internet
protocol software and a user interface shell), and is described in:

	Comer, Douglas E., Operating System Design Vol 2:
	  Internetworking with Xinu, Prentice-Hall, 1987.

   To run the software on this tape, you will need a Digital Equipment
Corp. VAX or Microvax computer running the Berkeley 4.3 UNIX operating
system, and at least one Digital Equipment Corporation LSI 11/2, LSI
11/03, LSI 11/23 with 64K bytes of main memory and a DEQNA Ethernet
interface.  The VAX is used to cross-compile, cross-assemble, and
cross-load C programs.  The cross-development software produces a
memory image for the LSI 11, which is then downloaded to the micro
over an Ethernet (or an RS232 line if your VAX does not have an Ethernet
interface).  Once downloaded, the micro runs independently, communicating
with the VAX or other machines over an Ethernet, using standard DARPA
Internet protocols (sometimes called TCP/IP).
   If no machines on your Ethernet support standard RARP, time, and
domain name servers, you can still experiment with the networking code
by dedicating one LSI 11 to run server software and running Xinu on other
LSI 11(s).  The source code and binary image needed for the server machine
are included on this tape and explained in the directions below.  We
recommend using standard servers if you have them, and using our (limited
capacity) servers only if you have no alternatives.
   The tape is self-contained.  It includes source programs for both
Xinu and the cross-development system.  The tape can be read into any
directory.  These programs do not need to be placed in system directories
unless you want to do so.  The cross-development software has changed
between the earlier versions and this release.  In particular, the
downloading software now handles multiple classes of identical machines,
automatically selects and reserves a free machine from a specified class,
and consults a database of machine descriptions to automatically select
a downloader appropriate for the machine.  For example, there is both a
serial line downloader and an Ethernet downloader for 11/23 machines that
have memory management and an Ethernet interface.  The database determines
which to use for a given machine.   A significant advantage of the database
approach is that it allows competition for a physical machine from multiple
classes of users.

Installation
------------

   Choose a directory for the Xinu software.  You need not be in this
directory to cross-compile or download programs -- it's merely the place
to store the Xinu software.  Moving the software to another directory
requires recompilation (i.e., reinstallation).  Choosing /usr/Xinu as
the directory will save time during installation because binary files on

Jan 14 09:12 1987  Xinu Version 7 Distribution Tape README Page 2

the tape are compiled for that directory.  Alternatively, you can choose
to place the software in an arbitrary directory and make a symbolic link
from /usr/Xinu to that directory.  Throughout this  documentation the
directory into which you place Xinu is denoted {Xinu-directory}.

   Make the Xinu directory and read in the tape by typing the following
commands:

	mkdir {Xinu-directory}
	cd {Xinu-directory}
	tar xbf 20 /dev/rmt0	(your 1600 bpi tape device may
				 be named something other than
				 /dev/rmt0)

   Make a symbolic link from /usr/Xinu to the directory you chose to
avoid recompilation.  You will need super user privilege to do so. This
step is optional:

	su
	...supply super user password when asked...
	ln -s {Xinu-directory} /usr/Xinu
	CONTROL-d (to leave super user mode)

Once the tape has been read, you must change all source programs that
refer to {Xinu-directory} and recompile the binaries.  A shell script
has been provided to do this for you.  To use it, move to the installation
directory and run Install.  *NOTE: YOU MUST BE IN THE INSTALLATION DIRECTORY
{Xinu-directory}/install WHEN YOU EXECUTE THIS SCRIPT OR IT WILL NOT WORK*

	cd {Xinu-directory}/install
	./Install

Connect LSI 11 to The VAX
------- --- -- -- --- ---

   We recommend setting your LSI 11 to use 9600 baud and the vendor's
standard console device address (octal 177560).  If you must use another
device address or speed, you can edit the downloading software in
{Xinu-directory}/src/cmd/download.  Speeds below 4800 baud are not
recommended because serial downloading becomes intolerable.

   Choose a tty line on the VAX and connect it to the LSI 11 console port.
Then modify the UNIX system so that it does not run a login process (getty)
on the tty device.  You need to be super user to do this.

	su
	...supply super user password when asked...
	ln /dev/{tty-that-you-chose} /dev/LSI.1
	...edit /etc/ttys; turn off getty on LSI tty line...
	kill -1 1
	chmod 0666 /dev/LSI.1
	CONTROL-d (to leave super user mode)

The cross-development system allocates an LSI whenever one is needed using
the database in {Xinu-directory}/lib/machines.  The default name for machine
are LSI.0, LSI.1, and so on.  Lock files in /tmp/xinu are used to specify the

Jan 14 09:12 1987  Xinu Version 7 Distribution Tape README Page 3

current machine owner.  Look at the reservation system software in
{Xinu-directory}/src/cmd/download/lib for details.

Compilation of Cross-Development Software
----------- -- ----------------- --------

   To complete installation you must recompile source programs that contain
references to the Xinu directory.  Shell scripts have been provided to do
the job.  For details, see file README in the installation directory:

	cd {Xinu-directory}/install
	cat README

Talk to the LSI 11
---- -- --- --- --

   Test the serial line that connects the VAX to the LSI 11 using program
{Xinu-directory}/bin/odt.  Odt connects your terminal to the LSI serial
line such that everything you type goes to the LSI 11 and everything the
LSI prints comes to your terminal.  Thus, you can talk to the LSI from
any terminal on the VAX (or from an rlogin session).
   Only three wires are needed on the RS232 connection between the
machines: data in, data out, and ground.  The most common problem you'll
have is getting the data-in and data-out connected the right way.  Try
swapping them if things don't work the first time.  The wires to swap are
on pins 2 and 3 of the 25-pin connector that plugs into the VAX.  The pin
configuration on the LSI interface boards can be found under the DLV11J
description in the vendor's hardware handbook.

	odt -cLSI
	...send a break using backslash followed by null...
	\CONTROL-@
	...you should get an @ prompt from the LSI...
	...your're talking to hardware ODT; try displaying memory...
	2/
	...you should see the contents of location 2...
	DEL or CONTROL-C to abort odt and return to the shell

Network Servers
------- -------

   Now that installation is complete, you need to Configure the Xinu
kernel software itself, and recompile it.  To do so, you must choose
internet addresses for the domain name server, time server, and remote
file server machines.  You can start the remote file server yourself
on the VAX.  It is found in {Xinu-directory}/bin/fs.  You need to know
the internet address of the VAX where fs runs, as well as the internet
address of the machine that runs a time server (UDP port 37) and the
internet address of a machine that runs a domain name server (UDP port
53).  Ask your local network guru to tell you these internet addresses
(in dotted decimal notation) and modify the SERVER constants found near
the end of file {Xinu-directory}/src/sys/sys/Configuration.  If you do
not have an assigned Internet address for your network (i.e., your network
does not connect to the DARPA Internet), choose network an address for it.
Using 128.10.2.0 (Which is actually the address of an Ethernet at Purdue),
means you won't have to recompile the kernel.

Jan 14 09:12 1987  Xinu Version 7 Distribution Tape README Page 4

	cd {Xinu-directory}/src/sys/sys
	...edit file Configuration; change SERVER address constants...
	make install

If your site does not have one or more of the required servers, or for
any reason you want to isolate Xinu machines on their own Ethernet, you
can still experiment with Xinu by having one of your LSI 11 machines
run simplified server code.  Just download the binary image in file
{Xinu-directory}/lib/serve11 onto one of the LSI 11 and use odt to
answer questions and set options.

	download -s -a5 -cSERVE11 {Xinu-directory}/lib/serve11
	odt
	...answer questions...
	DEL or CONTROL-c to abort odt and leave server running

The class "SERVE11" should map to a machine that is reserved for the
server.  See {Xinu-directory}/lib/machines (the machine database) for
details.

Remote File Server
------ ---- ------

   The remote file server answers queries from the network and reads/writes
files as directed.  If you run the file server on your VAX, then the file
server has the permissions of the user who starts it.  We recommend that you
install a new user account (e.g., "xinu"), and always execute the file server
as that user.  Also, you should understand that the file server makes all
world-readable files accessible over the network.  if you connect to the
DARPA Internet, it makes world-readable files accessible from foreign sites.
   The file server comes configured to use UDP port 2001.  Check with your
local network guru to make sure 2001 is not in use, and if it is, choose a
new port number for the file server.  Change the default port in the software
in {Xinu-directory}/src/fs or just use the -p option when invoking fs.  You
must also change the port number that the kernel uses - it can be found in
file {Xinu-directory}/src/sys/sys/Configuration.
   Start the file server:

	...login to the VAX under the account that owns the file server...
	{Xinu-directory}/bin/fs
	logout

Try Running Xinu
--- ------- ----

   Now that you have a network running RARP, time, and name servers,
you can boot xinu.  Download and run it.

	download -s -a5 -cLSI {Xinu-directory}/src/sys/sys/a.out
	odt
	...you should get Xinu boot message and login prompt...
	type any login
	...you should get prompt with machine name in it...
	...try commands such as the following...
	ps

Jan 14 09:12 1987  Xinu Version 7 Distribution Tape README Page 5

	date
	dg
	help
	mount
	...try accessing remote files as follows...
	rls /
	cat > /tmp/junk
	Hi there - this is a file
	created from Xinu
	CONTROL-D
	cat /tmp/junk
	...you should see what you just created...

Directories
-----------

   When the tar tape has been read, you will find a directory
structure like this:

1 .				Xinu-directory (usually /usr/Xinu)

  2 README			This file

  2 /bin			cross-development software

  2 /include			include files

  2 /install			installation shell script

  2 /lib			various libraries and data files

  2 /man			all manual pages for:
    3 /man1			cross-development commands
    3 /man2			Xinu system commands
    3 /man3			library commands
    3 /man4			device driver descriptions

  2 /src			all source programs:
    3 /cmd			cross-development software
    3 /lib			libraries
    3 /sys			Xinu and configuration:
      4 /con			configuration program
      4 /h			Xinu include files
      4 /sys			Xinu kernel and Makefile
	5 /shell		Xinu shell and commands
    3 /serve11			Server software for sites that need it
      4 /con			Server configuration
      4 /h			Server include files
      4 /sys			Server kernel and Makefile
        5 /shell		Server shell and commands

Server Directory
------ ---------

   The directory {Xinu-directory}/src/serve11 contains the software
that comprises the LSI 11-based RARP/time/name/file server.  It duplicates

Jan 14 09:12 1987  Xinu Version 7 Distribution Tape README Page 6

much of the Xinu kernel, and is not necessary at all sites.  You can
remove the directory entirely if you have standard network servers or if
you are satisfied to run the binary found in {Xinu-directory}/lib/serve11.

DEQNA Driver Explanation
----- ------ -----------

   The DEQNA driver configured in the kernel is NOT the same as that in the
text book.  The version installed here uses a timeout to circumvent the
hardware problem in early DEQNAs that causes them to hang.  If you have a
lightly loaded network, or a DEQNA built after the summer of 1986, you can
switch to the textbook driver.  Otherwise, we suggest you use the bullet-
proof version.

Problems or Questions
-------- -- ---------

Reports of errors in the software or documentation are gratefully accepted.
Please mail all comments and bug reports to:

	DARPA Internet/ CSNet address:
		comer @ cs.purdue.edu
	uucp address:
		{allegra, ihnp4} ! purdue ! comer
	Postal address:
		Computer Science Department
		Purdue University
		West Lafayette, IN  47907
		(317) 494-6009
----------------------------------------------------------------------------
Jan 14 20:37 1987  Xinu Version 7 Distribution Tape install/README Page 1

Installation Details
------------ -------

This is file {Xinu-directory}/install/README.  It contains
instructions for installing the Xinu software and recompiling
it.  These instructions instructions must be followed:
(a) after the distribution tape has been read in, or
(b) after the Xinu directory has been moved.

**************************************************************
***                     4.2BSD Users                       ***
*** NOTE: if you are still running 4.2bsd, you must remove ***
*** all the 4.3 files and libraries before doing anything  ***
*** else.  To do so, type the following:                   ***
***                                                        ***
***             cd {Xinu-directory}/install                ***
***             ./Install 4.2                              ***
**************************************************************

Installation involves changing references to {Xinu-directory}
in all source files and then recompiling them.

Step 1:	Execute shell script "Install" in this directory
	to climb around the tree and create final versions
	of the source files.  Look at the file sample.output
	to see what to expect.

		cd {Xinu-directory}/install
		./Install

Step 2:	Change to the source directory and execute the script
	that rebuilds binaries:

		cd {Xinu-directory}/src
		./Makeall > make.out &

	If you have installed Xinu in other than /usr/Xinu,
	recompilation takes about 30 minutes on a VAX 780
	(Hence, we suggest that you run it in background).
	Also be warned that there are numerous programs in
	the cross-development software that produce warning
	messages when recompiled.  Look at the the file
	sample.output to see what to expect.

	You do not need to be superuser; only directories
	under {Xinu-directory} are affected. 

Step 3:	Add {Xinu-directory}/bin to your "path" so you can
	execute	commands that are found there:

	C-shell users type:

		set path=( $path {Xinu-directory}/bin )

	Bourne shell users type:

Jan 14 20:37 1987  Xinu Version 7 Distribution Tape install/README Page 2

		PATH=$PATH:{Xinu-directory}/bin
		export PATH

	To make Xinu commands accessible after your next
	login, you must change the path assignment in your
	.profile or .cshrc files.

Step 4:	Try the command "odt" in {Xinu-directory}/bin. It
	connects your keyboard to an LSI 11 console input
	and output from the LSI 11 to your terminal screen:

		odt

	To get the attention of the LSI, type backslash
	followed by null (CONTROL @).  The LSI will stop
	execution and print a prompt ("at" sign).  You
	are now talking to the LSI's "ODT" mode (consult
	the vendor's manual for additional information on
	ODT).  To terminate the odt command, kill the
	process with your normal interrupt character
	(usually CONTROL-C or DELETE).

Step 5: Change back to the Xinu installation directory and
	download the test program:

		cd {Xinu-directory}/install
		download -a5 lsi.test
		odt

	It will print "hello world." and stop.  When all
	processes complete, type CONTROL-c to kill the odt
	command.

Step 6:	Pick one of your directories and make sure the
	cross-compiler works.

		cd directory-of-your-choice
		cp {Xinu-directory}/src/sys/sys/test.c .
		cc11 -o test.out test.c
		cmp test.out {Xinu-directory}/src/sys/sys/test.c

	Be sure you have the cross-compiler working before you
	change the operating system.

Step 7:	You are ready to experiment with Xinu itself.  Follow the
	instructions for configuring your network.  Change to the
	Xinu source directory and modify file Configuration to
	use your local network IP addresses.

		cd {Xinu-directory}/src/sys/sys
		...edit file "Configuration"...
		make a.out
		download -a4

Jan 14 20:37 1987  Xinu Version 7 Distribution Tape install/README Page 3

		odt

	Note that because recompiling the Xinu sources may take
	considerable time.  It is advisable to run make in the
	background with output (and error messages) directed to
	a file.  We usually direct output to file "make.out".

	Make will recompile the Xinu sources, rebuild file
	"xinu.o", and rebind library "libx.a".	However, it leaves
	the new versions in source directory.  Make also compiles
	file "test.c" and binds it with the new library to form file
	"a.out".  When you are satisfied that the new version works,
	run "make install" to copy the new kernel library into
	{Xinu-directory}/lib where command cc11 accesses it.

	Other arguments can be used with make.  For details see the
	file "Makefile".  Two that particularly	useful ones are
	"everything" that runs several scripts designed to test
	source program formats, and "d" that runs the commands
	"download -a4 ; odt" after remaking a.out.  Thus, you
	normally run "make d" after a change to recompile, download,
	and test the system.

Suggestions
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   Suggestions and reports of problems are welcomed.
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