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<!--startcut ==========================================================-->
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN"> 
<html>
<head>
<title>More 2 Cent Tips & Tricks Issue 21</title>
</head>

<BODY BGCOLOR="#FFFFFF" TEXT="#000000" LINK="#0000FF" VLINK="#0020F0"
ALINK="#FF0000">
<!--endcut ============================================================-->
<H4>&quot;Linux Gazette...<I>making Linux just a little more fun!</I>
&quot;</H4>
<P> <hr> <P> 

<!-- QUICK TIPS SECTION ==================================================  -->
<center>
<H1><A NAME="tips"><IMG ALIGN=MIDDLE ALT="" SRC="../gx/twocent.gif">
More 2&#162; Tips!</A></H1> <BR>
Send Linux Tips and Tricks to <A HREF="mailto:gazette@ssc.com">
gazette@ssc.com
</A></center>

<p><hr><p>
<H3>Contents:</H3>
<ul>
<li><a href="./lg_tips21.html#video">Changing Video Modes</a>
<li><a href="./lg_tips21.html#colormap">Colormap Questions</a>
<li><a HREF="./lg_tips21.html#netcat">Netcat!</a>
<li><a HREF="./lg_tips21.html#starting">Starting and Stopping Services</a>
<li><a HREF="./lg_tips21.html#tool">A New Tool for Linux</a>
<li><a HREF="./lg_tips21.html#logs">Of Logs and Other Things</a>
<li><a HREF="./lg_tips21.html#calc">Calculator Tip</a>
<li><a HREF="./lg_tips21.html#tarred">Another Way to View Tarred Files</a>
<li><a HREF="./lg_tips21.html#script">Script Ease</a>
<li><a HREF="./lg_tips21.html#syslog">Syslog Thing</a>
<li><a HREF="./lg_tips21.html#fax">Sorta E-mail-to-FAx...Well, to-Printer</a>
<li><a HREF="./lg_tips21.html#xterm">Setting Xterm Title to Current Process</a>
<li><a HREF="./lg_tips21.html#cvs">CVS</a>
</ul>

<P> <hr> <P> 
<!--================================================================-->

<a name="video"></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Changing Video Modes
</H3>
<P> 
Date: Fri, 08 Aug 1997 22:41:05 -0600<br>
From: Michael J. Hammel <a href="mailto:mjhammel@csn.net">mjhammel@csn.net</a><br>

<P>I don't know how AccelX and XiGraphics and MetroX handle these things.

<P>AccelX is ( I think) a PC graphics company.  You might mean Xaccel,
which is the actual program name for Xi Graphics X server.  Its product
name is "AcceleratedX".   Xi Graphics is the company name.

<P>As for how Xaccel changes its video modes - try CTRL-ALT-+ (thats a plus
sign).  I believe that cycles through the various modes.  Check the man
pages or manual to be certain.  I believe MetroX does similar, but the
keystroke is probably different.

<P>--

<P> <hr> <P> 
<!--================================================================-->

<a name="colormap"></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Colormap Question
</H3>
<P> 


Date: Fri, 08 Aug 1997 23:47:31 -0600<br>
From: Michael J. Hammel <a href="mailto:mjhammel@csn.net">mjhammel@csn.net</a><br>

<p>The question was "can you force an X application to use its own colormap
in some way other than using a command line option".  The answer is:  it
depends (aint it always the case?).

<p>An applications ability to use its own colormap is not a "builtin" part
of X.  Colormaps are part of X, but the application still has to add
code to make use of colormaps.  So if the application doesn't have any
code specifically for handling colormaps (for example, my XPostitPlus
doesn't have any such code) then neither the command line or any other
method will force it to use a private colormap.  The default for
applications (like XPostitPlus) is to use the default colormap, and
thats why you often see applications with weird colors that you can't
get rid of till you exit some other application.

<p>Now, if the application *does* have code to deal with colormaps, it can
also make the use of the private colormap a user configurable option.  X
provides a mechanism for making an option either a command line option
(eg. -usePrivateColormap) or an X resource.  X resources can be
specified in X resource files (like .Xdefaults) or on the command line
using the -xrm option.  X is so configurable that the number of ways for
a user to supply configuration information can often be quite confusing,
both for the user and the developer.  In any case, its up to the
programmer to make any of these methods available.  None is available by
default simply becaue its "an X windows program".

<p>The correct thing for an application to do is to allow the user to
configure the use of the private colormap in at least one way and to
provide a best-guess default for determining if a private colormap would
be the best thing to do or not if the user doesn't provide a
preference.  Few applications do this, however.  The GIMP does.  So do
XV and Netscape.  Even my own programs aren't very good at this,
although I intend to get much better in the very near future.

<p>As for an X column, well, I'd love to see one.  We just need to convince
some X hack to spend a little time writing articles instead of code.
Thats kinda hard to do.  I'll probably be adding some X coding tidbits
to my Muse column, but only with respect to using Motif or OpenGL in
graphical and multimedia applications.

<p>Hope this helps a little.
<p>
--
Michael  
<P> <hr> <P> 
<!--================================================================-->

<a name="netcat"></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Netcat!
</H3>
<P> 
Date: 01 Aug 1997 15:46 EDT<br>
From: Jean-Philippe Sugarbroad <a href="mailto:da1wizard@geocities.com">da1wizard@geocities.com</a>

<p>I was going through back issues of the Linux Gazette and I remembered a program
I use quite frequently... netcat.  This program enables you to open sockets and
connect or listen with them - all from a shell script!  It's a great way to
quickly fetch web pages or see if a server is running... It even has UDP
'connection' mode and zero-io mode (which closes the connection as soon as it
succeeds...).  The UDP mode even uses a TCP connection to check round-trip time
:)  I love it!

<p>Jean-Philippe Sugarbroad

<P> <hr> <P> 
<!--================================================================-->

<a name="starting"></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Starting and Stopping Services
</H3>
<P> 

Date: Tue, 5 Aug 1997 18:55:19 -0600 (CST)<br>
From: Terrence Martin <a href="mailto:twm139@its.to">twm139@its.to</a><br>

<p>I was just reading the August version of Linux Journal and I noticed
refrence to rebooting the system after making changes to the
/etc/syslog.conf file in order for those changes to take affect. This is
contrary to a feature that is the main reason I use Linux at home and at
work.

<p>It is only generally necessary to reboot Linux to add/remove hardware or
when installing a new kernel. In the specific case of syslogd(8) you can
inform the server to reread it's initialization file by sending it a
SIGHUP signal.
<pre>
eg.
kill -HUP `cat /var/run/syslogd.pid`
</pre>
<p>This will work with many of the servers available for Linux including
(most) httpd(8), named(8), and inetd(8). 

<p>Sometimes however it is preferable to actually restart these services. In
Slackware I believe most of your services are placed in a single script
and this makes it a little more difficult to pick and choose which
services to stop and start. 

<p>In RedHat it is a little more modular. In the directory /etc/rc.d/init.d
are the scripts that are run on bootup to start various services. 

<p>These scripts allow you to start and stop various services just as if you
had shutdown and rebooted your machine. eg.
<pre>
# /etc/rc.d/init.d/named.init stop 
# /etc/rc.d/init.d/named.init start
</pre>
<p>This will start and stop the name service.

<p>The scripts supplied with RedHat are not too complex compared to similar
scripts I have seen on other systems. They can usually be adapted to new
services that you may wish to have start on bootup, without complicating
the rc.local file and giving you much finer control.

<p>If you examine the soft links in /etc/rc.d/rc0.d through /etc/rc.d/rc6.d
you will notice that they link to the files in /etc/rc.d/init.d. Each of
these numbers on these directories refer to a "runlevel".

<p>As the system boots the /etc/inittab tells the init process which
directories to examine to determine which services to start up, most
systems not running xdm will end at runlevel 3, otherwise it is runlevel
5. 

<p>All of the files(softlinks) in runlevel 3 beginning with 'S' are executed
in order of occurance in the directory, this is controlled by giving each
a number ie
<pre>
S30syslog -> ../init.d/syslog comes before 
S40cron -> ../init.d/cron.init.</pre> 
Note: Links with the same number are executed in lexical order.

<p>The sequence may be important depending what services depend on other
services.

<p>I put most of the services I add in runlevel 3, as I usually boot into
multiuser mode. You then should add the approriate script link to
/etc/rc6.d as those are the files that are executed on shutdown. Note the
convention here is to begin all soft link names with 'K'. ie 

<pre>K10named.init -> ../init.d/named.init</pre>

<p>Again these scripts are executed on order with the highest number being
last to run. 

<p>The net effect of all these links is that with an 'S' preceding the soft
link the script is run with the argument "start" and with a 'K' it is run
with the argument "stop".

<p>Over the last two weeks I have set up and configured a news server, web
server, name server, sshd server, updated the syslog.conf file plus a
hundred other little tweaks on our RedHat 4.x box and I have not had to
reboot once. In fact the system has not been rebooted since we added a new
CPU and SCSI card 31 days ago...I love Linux :)...

<p>Regards<br>
Terrence Martin

<P><HR><P>
<!--================================================================-->

<a name="tool"></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
A New Tool for Linux
</H3>
<P> 

Date: Fri, 22 Aug 1997 08:29:59 -0500<br>
From: Ian <a href="mailto:Beth13@mail.utexas.edu">Beth13@mail.utexas.edu</a>

<p>The version posted in issue 20 assumes you have exec access to ALL dirs
under the one you 'TREE'

<p>Here's a modified version which works even in cases of unreadable
folders:
<pre>
-------------------------------- cut here --------------
#!/bin/sh
#         @(#) tree      1.1  30/11/95       by Jordi Sanfeliu
#                                         email: mikaku@arrakis.es
#
#         Initial version:  1.0  30/11/95
#         Next version   :  1.1  24/02/97   Now, with symbolic links
#         Patch by       :  Ian Kjos, to support unsearchable dirs
#                           email: beth13@mail.utexas.edu
#
#         Tree is a tool for view the directory tree (obvious :-) )
#
search () {
   for dir in `echo *`
   do
      if [ -d $dir ] ; then
         zz=0
         while [ $zz != $deep ]
         do
            echo -n "|   "
            zz=`expr $zz + 1`
         done
         if [ -L $dir ] ; then
            echo "+---$dir" `ls -l $dir | sed 's/^.*'$dir' //'`
         else
            echo "+---$dir"
            if cd $dir ; then
               deep=`expr $deep + 1`
               search    # with recursivity ;-)
               numdirs=`expr $numdirs + 1`
            fi
         fi
      fi
   done
   cd ..
   if [ $deep ] ; then
      swfi=1
   fi
   deep=`expr $deep - 1`
}

# - Main -
if [ $# = 0 ] ; then
   cd `pwd`
else
   cd $1
fi
echo "Initial directory = `pwd`"
swfi=0
deep=0
numdirs=0
zz=0

while [ $swfi != 1 ]
do
   search
done
echo "Total directories = $numdirs"


-------------------------------- cut here --------------
</pre>

<p>The changes are to put the "cd $dir" as the predicate of an IF
statement, NOT IN A SUBSHELL, and the recursive part is the switched
clause. This prevents infinite recursion in the case of an unreadable or
unexecable dir.


<P> <hr> <P> 
<!--================================================================-->

<a name="logs"></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Of Logs and Other Things
</H3>
<P> 
Date: Sun, 10 Aug 1997 21:47:39 +0200<br>
From: D. Emilio Grimaldo T. <a href="mailto:grimaldo@panama.iaehv.nl">grimaldo@panama.iaehv.nl</a><br>

<p>Hi,<br>
   I recently saw on the August issue of Linux Gazzete and some
previous issues about the handling of system logs. Well, it
doesn't have to be complicated, in fact I have written a very
useful script/package that has been around for a couple of
years, it is called Chklogs and is used by major network providers,
companies and small-time users of Linux systems. In fact it is
going to be featured in the Linux Journal some time this year.
IT fulfills all the log handling needs. For more information
see
<a href="http://www.iaehv.nl/users/grimaldo/info/">http://www.iaehv.nl/users/grimaldo/info/</a>

<p>Catch the link to Chklogs

<p>		Best Regards,<br>
				Emilio


<P> <hr> <P> 
<!--================================================================-->

<a name="calc"></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Calculator Tip</H3>
<P> 
Date: Sun, 27 Jul 1997 23:43:37 +0200 (MET DST)
From: Hans Zoebelein <a href="mailto:zocki@goldfish.cube.net">zocki@goldfish.cube.net</a><br>

<p>Hello Linux Gazetters,<br>

Here comes a real cheap command line calculator.
Since shell scripts do only integer calculation,
you are stuck if you want floating point precision.

<p>You also want to do sometimes stuff like 'how much is 
1200*3/7' at the commandline without firing up a full 
blown GUI calculator.

<p>Just for that work you can use the <tt>calcme</tt> command line 
calculator, which is hacked in perl. Dont forget that a shell 
thinks differently about 10*3 than a calculator. So do it as 
10\*3 or "10*3".

<p>The icing of the cake is the optional formatting. If you supply
something like <tt>%.3f</tt> as second parameter, the output is nicely 
formatted as floating point number and up/down rounded correctly 
after 3 decimals.

<p>You also can do a <tt>calc 10/3 %20.6f</tt> which returns a string 
with 6 digits and 20-6=14 spaces like <tt>______________3.3333</tt>. 
So formatting of lists in shell scripts is real fun now.    

<p>Enjoy!<br>
Hans
 

<pre>#!/usr/bin/perl

#
# The ultimate command line calculator :-^
# Usage calcme &lt;string_to_calculate&gt; [&lt;output_format&gt;]
#

# Input is a string like (10+3)/7 or "(10 + 3) / 7"
# Output is the calculated result of the string (sic!).
# Optional formatting can supplied as 2nd parameter. 

if (@ARGV == 0 || @ARGV &gt; 2)
{
   die("Usage: $0 &lt;\"formula_to_calculate\"&gt; [&lt;output_format&gt;]\n");
}	

$format = "";
$calcme = $ARGV[0];
(@ARGV == 2) && ($format = $ARGV[1]); 

$output = eval($calcme);

if(@ARGV == 1)
{
   print(STDOUT "$output\n");
}
else
{
   printf(STDOUT "$format\n", $output);
}
exit(0);
</pre>
<p>
--
Hans 


<P> <hr> <P> 
<!--================================================================-->

<a name="tarred"></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Another Way to View Tarred Files</H3>
<P> 
Date: Sat, 02 Aug 1997 02:18:07 +1000 (GST)
From: Gerald J Arce <a href="mailto:garce@starcommand.mang.net">garce@starcommand.mang.net</a>

<p>In issue 19, I read a 2 cents tip regarding viewing a tarred file.

I use less instead..
<pre>
ex:
tar tzf foo.tar.gz

less foo.tar.gz
</pre>
Less typing (grin).

<P> <hr> <P> 
<!--================================================================-->

<a name="script"></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Script Ease       </H3>
<P> 
Date: Wed, 6 Aug 1997 01:54:19 +0200 (GMT+0200)
From: Trucza Csaba <a href="mailto:ctrucza@cemc.soroscj.ro">ctrucza@cemc.soroscj.ro</a>

<p>Hi all,
<p>As a programmer-wannabe, I do a lot of typing. To ease at least the 
beginning of each source file (which is mainly the same: include-s, 
define-s, imports and stuff), I wrote a script to automatize this. For 
the quality of the script please read the notice at the end of my mail.

<pre>(file: se)
---------cut here---------------
#!/bin/sh
#
# 	source editor (se)
#
#	usage: se &lt;filename&gt; &lt;type&gt;
#
#	WARNINGS:
#		1. do not supply extension:
#			se MyProg.java will make a MyProg.java.java!!!
#
#		2. manually create the 
#			SE_HOME_DIR, 
#			SE_HOME_DIR/temp,
#			SE_HOME_DIR/templates
#
#	man se:
#
#	create two files for each type of the source you want to se.
#	the script will copy the first file+filename+second file into a new
#	file (you got it?:-)
#
#	so: if you want java, create two files:
#
#	templates/java.1:
#
#	---8&lt;---
#	public class
#	--->8---
#	(Do not put a newline at the end!)
#
#	templates/java.2
#
#	---8&lt;---
#	{
#		public static void main(String args[]){
#		}
#	}
#	---&gt;8---
#	
#	the script for se MyProg java (or jus se MyProg if the last time you
#	used java as type) will create a new file called MyProg.java:
#
#	public class MyProg
#	{
#		public static void main(String args[]){
#		}
#	}
#
#	examine and modify at will
#
#	author: Trucza Csaba ctrucza@cemc.soroscj.ro
#
#	this script may be full of errors
#

SE_HOME_DIR=~/.source-editor
LAST_USED=$SE_HOME_DIR/last_used

if [ -f $LAST_USED ] ; then
	SE_DEFAULT_TYPE=`cat $LAST_USED`
fi

case $# in
	0)
	echo "no parameter"
	if [ -z $SE_DEFAULT_TYPE ] ; then
		SE_DEFAULT_TYPE=java
	fi
	FILE_TYPE=$SE_DEFAULT_TYPE
	FILENAME=~/.source-editor/temp/temp.$FILE_TYPE
	;;
	1)
	echo "filename"
	if [ -z $SE_DEFAULT_TYPE ] ; then
		SE_DEFAULT_TYPE=java
	fi
	FILE_TYPE=$SE_DEFAULT_TYPE
	FILENAME=$1.$FILE_TYPE
		;;
	2)
	echo "name and type"
	FILE_TYPE=$2
	FILENAME=$1.$FILE_TYPE
	;;
esac

echo "FILE_TYPE="$FILE_TYPE
echo "FILENAME="$FILENAME


if [ -f $FILENAME ]; then
	echo file exists
else
	build-template $FILE_TYPE $1
	mv ~/.source-editor/templates/$FILE_TYPE.template $FILENAME
fi
echo $FILENAME
echo $FILE_TYPE &gt; $LAST_USED

jstar -tab 4 $FILENAME
---------cut here---------------
</pre>

<p>The second script is a simple backup script, to back all the sources up 
and edit the tracking file. 

<pre>(file: backup)
---------cut here---------------
#!/bin/sh
#
# 	kind of backup with kind of version control
#	usage: backup
#
#	backs up the current directory (well not all of it, just your
#	programs) 
#
#	1. creates a dir named backup (or whatever)
#	2. in this directory will be a tracking file, a plain text file
#		in which you can write some comments every backup
#	3. optionally in the file named filelist you can write the names of
#	the files you want to back up
#	4. examine and modify at will
#
#	author: Trucza Csaba ctrucza@cemc.soroscj.ro
#
#	this script may be full of errors
#

#
#	where to back up
#
if [ -z $BACKUPDIR ] ; then
	BACKUPDIR=backup
fi

if [ ! -d $BACKUPDIR ] ; then
	mkdir $BACKUPDIR
fi

#
#	last version backed up
#

LAST_FILE=$BACKUPDIR/last

if [ -f $LAST_FILE ] ; then
	VERSION=`cat &lt;$LAST_FILE`
else
	VERSION=0
fi
let VERSION=$VERSION+1

#
#	prepare next backup directory
#

NEXT_DIR=$BACKUPDIR/ver.$VERSION

mkdir $NEXT_DIR

#
#	get files to back up
#

LIST_FILE=$BACKUPDIR/filelist

if [ -f $LIST_FILE ] ; then
	cp `cat $LIST_FILE` $NEXT_DIR
else
#
#	if no filelist found, backup C and Java files
#	modify as you wish
#
	cp *.c $NEXT_DIR &gt;/dev/null 2>&1
	cp *.h $NEXT_DIR &gt;/dev/null 2>&1
	cp *.java $NEXT_DIR &gt;/dev/null 2>&1
fi

#
#	update last
#

echo $VERSION &gt;$LAST_FILE

#
#	edit trackfile
#

TRACK=$BACKUPDIR/track

echo &gt;&gt; $TRACK
echo &gt;&gt; $TRACK
echo "=====================================================================">> $TRACK
date &gt;&gt; $TRACK
echo "Version: "$VERSION &gt;&gt;$TRACK

#
#	here use your favorite editor :)
#
jstar $TRACK
---------cut here---------------
</pre>

<p>They should be self-explanatory. 
but,
These scripts should not be used  for design or development of nuclear, 
chemical, biological, weapons or missile technology, or any other places 
where humans can be hurt


<P> <hr> <P> 
<!--================================================================-->

<a name="syslog"></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Syslog Thing</H3>
<P> 
Date: Thu, 07 Aug 1997 15:00:29 -0700<br>
From: Kent Friis <a href="mailto:dk5f@ehs.dk">dk5f@ehs.dk</a>

<p>In issue 20, I saw a 2c tip regarding syslog, Including changing the config 
file, and REBOOTING. Now wait a minute, I thought this was Linux. How can
one get uptime's of 300+ days, if you need to reboot every time you change
a config file.

<p>The solution is simply to edit the config file, and kill -HUP (pid of
syslogd).

<p>You should NEVER need to reboot, except to install a new kernel.

<p>Kent Friis.

<P> <hr> <P> 
<!--================================================================-->

<a name="fax"></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Sorta E-mail-to-Fax...Well to-Printer</H3>
<P> 
Date: Fri, 8 Aug 1997 20:04:30 +0500 (PKT)<br>
From: Tee Emm <a href="mailto:tm@super.net.pk">tm@super.net.pk</a>

<p>Hello,

<p>I can bet that many of you readers will try out this tip atleast for once.
Here we go:

<p>I work at an ISP here in Pakistan with 4 more shift engineers. We have
offices in three different locations and, although email and talk are
used very frequently, we sometime require ABSOLUTELY IMMEDIATE responce
from the other office. Emails remain unchecked and talk request are
sometimes ignored because the other party might be busy doing something
else on a talk-disabled terminal. Well, you cannot ignore a Panasonic
Dotmatrix printer printing out messages in your control center!

<p>One of my so-to-say boss talked of having a utility which will poll a POP3
mailbox every few seconds and printing out any mail that might be in the
box. He, being a visual basic guru, started writing a windows based
application that would do the required. I, being a die hard Linux
creature, started thinking how I can do the same on my dear Linux box.
Well, it took me a day to ponder on this issue and when I clicked, it was
just a breeze! Sixteen key strokes and I was ready with my system. I
yelled 'Windoz Suxs, Linux Rules'!

<p>I edited the /etc/aliases file and keyed in the following line:
<pre>
urgent: 	"| lpr"
</pre>
saved, the file and did a 'newaliases' and bingo! Any mail sent to
urgent@super.net.pk was immediately printed on the screaming dot matrix
printer. My boss was duly stunned!

<p>(Note: You must have your 'lpr' command working before you can go ahead
with this tip.)

<p>Tariq Mustafa,

<P> <hr> <P> 
<!--================================================================-->

<a name="xterm"></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Setting Xterm Title to Current Process</H3>
<P> 
Date: Tue, 12 Aug 1997 01:09:02 -0500 (CDT)<br>
From: Rob Mayoff <a href="mailto:mayoff@dqd.com">mayoff@dqd.com</a><br>

<p>I saw this tip the Gazette:

<B>Hi, after searching (to no avail) for a way to display the currently
executing process in the xterm on the xterm's title bar, I resorted to
changing the source of bash2.0 to do what I wanted. from line 117 of
eval.c in the source, add the lines marked with # (but don't include
the #)</B>

<p>If you use ksh instead of bash, you can get the same effect
without changing the source:

<pre>typeset -A Keytable
trap -- 'eval "${Keytable[${.sh.edchar}]}"' KEYBD
[[ "$TERM" == xterm ]] && \
Keytable[$'\r']=$'[[ -n ${.sh.edtext} ]] && print -n "\E]2;${.sh.edtext}\a"'
</pre>
<p>You can download ksh (the POSIX-compliant Korn shell) for free from

  <a href="http://www.research.att.com/orgs/ssr/book/reuse">http://www.research.att.com/orgs/ssr/book/reuse</a>


<P> <hr> <P> 
<!--================================================================-->

<a name="cvs"></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
CVS</H3>
<P> 
Date: Thu, 14 Aug 1997 11:08:27 -0400<br>
From: Paul Rensing <a href="mailto:paulr@dragonsys.com">paulr@dragonsys.com</a>

<P><B>Mario Storti wrote:</B>

<P><B>Using shar + RCS to Backup Set of Source Files</B> 

<p><B>Hi, RCS (see rcs(1)) is a very useful tool that allows to store versions of
a file by storing only the differences between successive versions. In this
way I can make a large amounts of backups of my source files but with a
negligible amount of storage. I use it all the time, even for TeX files!!
However, when you are working with a set of source files (*.c, shell or
Perl scripts, I work mainly with Fortran .f and Octave *.m files) what I
want is to make backups of the whole set of files in such a way that you
can recover the state of the whole package at a given time. I know that
there is a script called rcsfreeze around, but I know that it has problems,
for instance if you rename, delete or create new files, it is not
guaranteed to recover the same state of the whole set.</B>

<p>I think a good way to handle this is by "upgrading" to CVS. CVS is a version
control system built on top of RCS and was designed specifically to handle
version control of large trees of files (the company who wrote it was a Sun
VAR and handled the &gt; 1000 files which they regularly received from Sun).

<p>Once you have the project set up, you could simply do "cvs commit" from the
top directory of a project, and CVS will check in all the changes to all the
controlled files in the tree. If you are using this for "backup", you would
only need to keep a copy of the CVS "repository".

<p>Paul Rensing


<P> <hr> <P> 
<!--================================================================-->
<center>Published in Linux Gazette Issue 21, September 1997</center>
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