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___________________________________________________________________

issue  9                    http://console-newsletter.hypermart.net
 __  __  _ _  __ __  )) __  console: tips,tricks & news about linux
((_ ((_)((\( _))((_)(( (('_ _______________________________________

[5/2000]                                            "a good read.."

+ headlines

Pizza-Pizza

"Next time you buy a pizza at Little Caesars, the clerk at the
cash register might well be using a Linux computer."

"MaxSpeed makes hardware that lets companies plug numerous
sets of keyboards, pointing devices and monitors into a single
Linux server.  The hardware, which is being used at FTD, Little
Caesars and others, is geared for use at chain stores that have
numerous outlets."

http://news.cnet.com/news/0-1003-200-1584128.html?tag=st.ne.1002.thed.1003-200-1584128
--

+ hmm..

"Wall Street analysts and information technology managers are
watching to see if Linux reaches a fork in the road - with
incompatible versions of the popular free operating system
competing for adoption at small and large corporations. If
branches emerge, the value of the open source operating system
is likely to plummet."

http://www.zdnet.com/intweek/stories/news/0,4164,2470425,00.html

Pure hog-wash from the cronies at zdnet, they complain about
a 'fork' among Linux vendor's for example - w/ lib5 and lib6
while totally ignoring the fact that, when compiled from source
(packaging aside) all distros are essentially the same. Just click
the WIN2K banner and they'll forgive you, sorta makes you go,
"hmm.."
--

+ humorix

Windows NT Beats Turned-Off Linux Box

"Microsoft is touting the results of an independent study that
compares the networking speeds of Windows NT and a computer
loaded with Linux that was turned off."

http://www.sjswebhack.com/microfits/prev/mstest.htm
--

+ new! whatis

(note: "whatis" is a *nix command w/ a short one line
description of a command.)

uniq - remove duplicate lines from a sorted file
--

+ distro watch

Red Hat Linux 6.2:
http://www.redhat.com/

Finnix - self-contained, bootable Linux CD distribution:
http://www.finnie.org/finnix/
--

+ new apps

rute 0.3.0 - aims to be the definitive guide for new users:
http://www.obsidian.co.za/rute/

envelope 0.625 - full-featured envelope printer written in Perl:
http://freefall.homeip.net/code/envelope/

Zdisk 1.53 - rescue system on one floppy disk:
ftp://metalab.unc.edu/pub/Linux/system/recovery/
--

+ article

rsh (remote shell) - digs <mjs@nts-online.net>

Have you ever needed to run a command on a remote unix machine,
or maybe copy some files to/from a different host but didn't
want to hassle with telnet or ftp? Most Linux distros ship with
the rsh suite which comprise some very handy commands:

rsh - remote shell
rcp - remote copy
rlogin - remote login

Hold on hotrod...

Before we get down to the facts, take note: the r[commands]
are -not- at all secure. Which means someone sniffing your
net-work can breech security. If this is a concern then
checkout SSH (secure shell) at:
http://www.employees.org/~satch/ssh/faq

Ok back to our previously scheduled article :-)

Use of the rsh commands requires four things:

1. the r[commands] must be on your machine
2. the remote box -must- be running the rshd daemon
3. an ~/.rhosts file on the remote boxen
4. (of course) some type of networking between the machines

The host will probably run the daemon via inetd.conf
here's a typical entry:

shell   stream  tcp     nowait  root    /usr/sbin/tcpd  in.rshd -L
login   stream  tcp     nowait  root    /usr/sbin/tcpd  in.rlogind

Your ~/.rhosts file (on the remote) contains several two column
entries of -trusted hosts- and your -remote- login name.
By way of telnet login into the remote host and with a editor
create the .rhosts in your home directory like so:

full_server_name login_name
some_other_place login_name

To clarify the syntax is, <local.server.com> <joe>
where <local.server.com> is the -full- name of the local host.
and <joe> is the proper login on the remote host your attempting
to use.
(hint, listing each machine in the others /etc/hosts file
never hurts)

note the commands:

`hostname -l` (on the local box) will give you the full host name
`whoami` (from the remote) will give you the proper login on
the remote

After you've edited the file, next you'll want to set the proper
permissions or the rshd daemon will deny you access and verbally
abuse you, from the remote:

chmod 600 ~/.rhosts

this makes the file owned and readable by you only. The output of,

`ls -l ~/.rhosts` ought to look something like this:
-rw-------   1 mjs      users          39 Oct 22 22:11 .rhosts

Now we should be ready for a test run. Enter the command:

rlogin remote_host_name

If you get prompted for a password then something is wrong,
reread the above. Assuming the initial test worked logout out
from the remote host and lets go to the next set of examples:

rsh -l <remote_user> <remote_host> <remote_command>
or
rsh -l joe some_host.com date

This should produce a response from some_host.com showing the
output of the date command on your screen.
note: If you omit the -l switch then rsh uses your local login
name.

So far so good, here are some more to try:

copy from remote to local:
rcp <remote_user>@<remote_host>:<remote_file> <local_file>
or
rcp joe@some_host.com:/home/joe/sample.txt sample.txt

copy from local to remote:
rcp <local_file> <remote_user>@<remote_host>:<remote_file>
or
rcp sample.txt joe@some_host.com:/home/joe/sample.txt

Some nifty tricks:

You can copy files from several hosts with one command:
rcp joe@host1:/tmp/file1 wendy@host2:/tmp/file2 file.out

Link the `rsh` command to a host name for ease of use:
ln -sf /path/to/rsh remote_host_name
then you can run commands like,
some_host date
some_host who
some_host mail

To return the exit code (to check for errors) on the remote,
rsh some_host "command ; echo $?"
--

+ quote of the month

"Duct tape is like the force. It has a light side,
a dark side, and it holds the universe together."
-Carl Zwanzig
--

+ grok

If you want to change your shell, use the `chsh` command.
Note: you will only be able to use root approved shells
as specified in /etc/shells

To use a text mode other than the default 80x25, such as 80x50
or even 132x60, put vga=ask into your lilo.conf file and then
run lilo.  When you reboot it will let you choose your video mode.
When you decide which one you want, you can put vga=n where n
is the number of the video mode you would like.
--

+ jargon

:ad-hockery: /ad-hok'*r-ee/ n. [Purdue] 1. Gratuitous assumptions
made inside certain programs, esp. expert systems, which lead
to the appearance of semi-intelligent behavior but are in fact
entirely arbitrary. For example, fuzzy-matching of input tokens
that might be typing errors against a symbol table can make it
look as though a program knows how to spell. 2. Special-case
code to cope with some awkward input that would otherwise cause
a program to {choke}, presuming normal inputs are dealt with in
some cleaner and more regular way.
--

+ hobbes' internet timeline

1974
BBN opens Telenet, the first public packet data service
(a commercial version of ARPANET)

1975
First ARPANET mailing list, MsgGroup, is created by Steve
Walker. Einar Stefferud soon took over as moderator as the list
was not automated at first. A science fiction list, SF-Lovers,
was to become the most popular unofficial list in the early days.

Satellite links cross two oceans (to Hawaii and UK) as the first
TCP tests are run over them by Stanford, BBN, and UCL.
--

+ article

Passing arguments to your script - digs <mjs@nts-online.net>

1. From batch files to scripting

Initially coming from a DOS world I found that shell scripting(sh)
in Linux was volumes stronger than batch files under command.com,
(the default shell under DOS). But one aspect that always seemed
to elude me was the passing of arguments under the bash shell.
After much trial & error (& some help from friends) I finally
came across the formula! Guru's out there will know this, and
the rest of us will find this little tutorial quite enlighting.

2. This file, that file, grrr... to many files!

For instance in slackware it takes _two separate scripts_
to manipulate my dial up connection: 'ppp-go' and 'ppp-off',
sigh... there must be a better way of doing this I remember
thinking. What I wanted was something like: 'net -on' and 'net
-off' the idea being ONE command with options.

3. A better way

As I discovered this is really simple. The secret is the use
of the "case" statement and "place markers" The case statement
simply filters a variable and a place marker is a positional
indicator. When you enter a command at the shell it has a
place marker:

prompt# command
command = $0

When you pass arguments to a command they also have place markers:
prompt# command argument
argument = $1

so, grep foo file = $0 $1 $2

4. Some examples

#! /bin/sh
case "$1" in
    a)
       echo "You entered: a"
       ;;
    b)
       echo "You entered: b"
       ;;
    c)
       echo "You entered: c"
       ;;
    *)
       echo "Usage: $0 {a|b|c}"
       exit 1
       ;;
esac
exit 0

Let's suppose you use three editor's and for the sake of
efficiency wanted to use only one command (and an argument)
to use any of the three.

#! /bin/sh
# dont forget to `chmod +x this_file` to make it executable.
# $0 is the name of your script, $1 is the editor, $2 is the 
# file to edit

case "$1" in
   -j) #jed
      /path/joe "$2"
      ;;
   -v) #vim
      /path/vim "$2"
      ;;
   -e) #emacs
      /path/emacs "$2"
      ;;
   *) #user input not matched
      clear
      echo "Usage: $0 {-j|-v|-e} file"
      echo "You must specify an option, ONE of:"
      echo "j=joe, v=vim, e=emacs"
      exit 1
      ;;
esac
exit 0

5. Using the script

Invoking our script would work like this, to open "file"
with "joe" as the editor:

script -j file

6. Conclusions

Study the above examples and you'll quickly think of several
different uses. You can group several tools together in a master
script and save yourself a whole lot of typing. Good luck.
--

+ funnies
 _______
(_)___oo) Ned the log ------------- . Particle man ----------------
   _______                         |  \|
 _(_)oo___)_                       |. }------
(_)oo(_)__oo)  Ned family portrait |  /|          dragonfly chasing
                                   |              particle man
-------------------------------------------------------------------
--

+ wrap up

Coming next issue:

Which distro should I use? - a reader tells all in this humorous
article.

Use a swap-file instead of a swap-partition.

The antics of Ned and particle man and plenty of
links to browse.

console is not very far from 500 subscribers, & I'm simply amazed.
As much a I'd like to take credit for that its you all that make
this possible. My earnest thanks for the articles; email & of
course all you loyal readers :) And as always, a warm welcome to
new subscribers, if you have an idea or point of view you'd like
to get across then here is your chance to make a splash. Just
drop me a quick note along with your article and your ready to go!

later on,
digs
--

+ subscriptions & submittals

To subscribe send a blank email to: console-subscribe@topica.com
To unsubscribe send a blank email to:
   console-unsubscribe@topica.com

To submit an article:
http://console-newsletter.hypermart.net/

Past issues can be found at:
http://console-newsletter.hypermart.net/old/
--

+ about

This issue of console was brought to you by:
digs <mjs@nts-online.net> - chief writer & layout


Hobbes' Internet Timeline (c)1993-9 by Robert H Zakon.
http://www.isoc.org/zakon/Internet/History/HIT.html

Console (c)99-00 Michael S Sanders, All Rights Reserved.
--

eof