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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN">
<HTML>
<HEAD>
<TITLE> Linux Gazette Front Page </TITLE>
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<BODY>
<center><H2>
<IMG SRC="../gx/banner.gif"
ALT="Linux Gazette... making Linux just a little more fun!">
</H2>
<H5>Copyright &copy; 1996-97 Specialized Systems Consultants, Inc.
<A HREF="mailto:linux@ssc.com"><I>linux@ssc.com</I></A></H5>
</center>
<P> <HR> <P>
<!--==================================================================-->
<H2>Welcome to Linux Gazette!<img src="../gx/tm.gif" alt="(tm)"></H2>
<P>
<I>Linux Gazette</I>, a member of the Linux Documentation Project, is
an on-line WWW publication that is dedicated to two simple ideas:
<UL>
<LI>Making Linux just a <I>little</I> more fun
<LI>Sharing ideas and discoveries
</UL>
<P> <HR> <P>
<!--=================================================================-->
<center><H1>Table of Contents Issue #13</H1></center>
<P> <HR> <P>
<table><tr>
<td rowspan=2>
<UL>
<LI><A HREF="../index.html">The Front Page</A>
<LI><A HREF="./lg_mail13.html">The MailBag</A>
<ul>
<li><a HREF="./lg_mail13.html#help">Help Wanted -- Article Ideas</a>
<li><a HREF="./lg_mail13.html#gen">General Mail</a>
</ul>
<LI><A HREF="./lg_tips13.html">More 2 Cent Tips</A>
<ul>
<li><a HREF="./lg_tips13.html#free">Another 2cent Tip for LG</a>
<li><a HREF="./lg_tips13.html#console">Console Trick Follow-up</a>
<li><a HREF="./lg_tips13.html#gif">GIF Animations</a>
<li><a HREF="./lg_tips13.html#adm">How to close and reopen a new /var/adm/messages file</a>
<li><a HREF="./lg_tips13.html#admin">How to truncate /var/adm/messages</a>
<li><a HREF="./lg_tips13.html#infozip">Info-ZIP encryption code</a>
<li><a HREF="./lg_tips13.html#kernel">Kernel Compile Woes</a>
<li><a HREF="./lg_tips13.html#title">Letter 1 to LJ Editor re Titlebar</a>
<li><a HREF="./lg_tips13.html#more">Letter 2 to LJ Editor re Titlebar</a>
<li><a HREF="./lg_tips13.html#redial">PPP redialer script--A Quick Hack </a>
<li><a HREF="./lg_tips13.html#table">TABLE tags in HTML</a>
<li><a HREF="./lg_tips13.html#undelete">Text File undelete</a>
<li><a HREF="./lg_tips13.html#var">Truncating /var/adm/messages</a>
<li><a HREF="./lg_tips13.html#host">2c Host Trick</a>
<li><a HREF="./lg_tips13.html#tcsh">Use of TCSH's :e and :r Extensions</a>
<li><a HREF="./lg_tips13.html#notes">Various notes on 2c tips, Gazette 12</a>
<li><a HREF="./lg_tips13.html#howto">Viewing HOWTO Documents</a>
<li><a HREF="./lg_tips13.html#xaw">Xaw-XPM .Xresources troubleshooting tip</a>
<li><a HREF="./lg_tips13.html#xterm">Xterm Titlebar</a>
</ul>
<LI><A HREF="./lg_bytes13.html">News Bytes</A>
<ul>
<li><a HREF="./lg_bytes13.html#general">News in General</a>
<li><a HREF="./lg_bytes13.html#software">Software Announcements</a>
</ul>
<LI><A HREF="./answer.html">The Answer Guy</A>, by James T. Dennis
<ul>
<li><a HREF="./answer.html#dialup">Dialup Problem</a>
<li><a HREF="./answer.html#file">File Referencing</a>
<li><a HREF="./answer.html#modem">Combining Modems for More Speed</a>
<li><a HREF="./answer.html#server">WWW Server</a>
</ul>
<LI><A HREF="./comdex.html">Comdex '96</A>, by Belinda Frazier & Kevin
Pierce
<LI><A HREF="./filter.html">Filtering Advertisements from Web Pages using IPFWADM</A>, by David
Rudder
<LI><A HREF="./floppies.html">Floppy Disk Tips</A>, by Bill Duncan
<LI><A HREF="./gm.html">Graphics Muse</A>, by Michael J. Hammel
<ul>
<LI><A HREF="./png.html">History of Portable Network Graphics Format</A>, by Greg Roelofs
</ul>
<LI><A HREF="./smart.html">Indexing Texts with Smart</A>, by Hans Paijmans
<LI><A HREF="./editors.html">Linux Text Editors and A New One</A>, by Oleg L. Machulskiy
<LI><A HREF="./tkmail.html">New Release Reviews</A>, by Larry Ayers
<ul>
<LI><A HREF="./tkmail.html">Two New X Windows Mail Clients</A>
<LI><A HREF="./misc.html">Miscellaneous Notes</A>
</ul>
<LI><A HREF="./tmark.html">Petition to Cancel Filed Against Linux Trademark</A>
<LI><A HREF="./slew.html">SLEW: Space Low Early Warning</A>, by James T. Dennis
<LI><A HREF="./lg_backpage13.html">The Back Page</A>
<ul>
<li><a HREF="./lg_backpage13.html#authors">About This Month's Authors</a>
<li><a HREF="./lg_backpage13.html#notlinux">Not Linux</a>
</ul>
</UL>
</td>
<td align=center><a href="gm.html">
<A HREF="gm.html">
<IMG SRC="../gx/hammel/banner-3.gif" border=0 alt=""></a>
</a>
</td>
</tr><tr>
<td align=center><img src="../gx/fisk/greasgun.gif" border=0 alt="">
<p>
Weekend Mechanic <BR>
will return next month.
</td>
</tr></table>
<P> <HR><P>
<!--=============================================================-->
<A HREF="./issue13.txt">TWDT 1 (text)</A><BR>
<A HREF="./issue13.html">TWDT 2 (HTML)</A><BR>
are files containing the entire issue: one in text format, one in HTML.
They are provided
strictly as a way to save the contents as one file for later printing in
the format of your choice;
there is no guarantee of working links in the HTML version.
<!--=============================================================-->
<P> <HR><P>
Got any <I>great</I> ideas for improvements! Send your
<A HREF="mailto:gazette@ssc.com">comments, criticisms, suggestions
and ideas.</A>
<P><hr><p>
This page written and maintained by the Editor of <I>Linux Gazette</I>,
<!--=============================================================-->
<P> <HR><P>
<H4>&quot;Linux Gazette...<I>making Linux just a little more fun!</I>&quot;</H4>
<HR>
<center>
<table width="100%" cellpadding=7><tr><td>
<H2><a NAME="mail"><IMG SRC="../gx/mailbox.gif" ALIGN=MIDDLE ALT=" ">
The Mailbag!</a> </H2>
Write the Gazette at <A HREF="mailto:gazette@ssc.com"> gazette@ssc.com</A>
</td><td>
<H3>Contents:</H3>
<ul>
<li><a HREF="./lg_mail13.html#help">Help Wanted -- Article Ideas</a>
<li><a HREF="./lg_mail13.html#gen">General Mail</a>
</ul>
</td></tr></table>
</center>
<a name="help"><p></a>
<p><hr><p>
<!-- =================================================================== -->
<center><H3> Help Wanted -- Article Ideas </H3></center>
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Sun, 17 Nov 1996 18:49:56 -0600 <BR>
Subject: <B> a reply type thing...</B> <BR>
From: Glenn E. Satan, <A
HREF="mailto:insipid@onramp.net">insipid@onramp.net</A><BR>
<PRE>
> Subject: Xwindows depth
> From: James Amendolagine uq274@freenet.victoria.bc.ca
>
> I have recently been messing with my x-server, and have managed
> to get a depth of 16, ie 2^16 colors. This works
> really nice with Netscape, but some programs (doom, abuse, and
> other games) wont work with this many colors. Do
> you know of a fix? I have tried to get X to support multiple
> depths--to no avail. The man-page suggests that some
> video cards support multiple depths and some don't. How do I know
> if mine does.
>
> I would really like to see an article on this subject,
</PRE>
I would like to say, yes, please someone help.... thought maybe a reply
would motivate someone a little more to write a article on this.
<blockquote> <I>
(All right a second request for help in this area. Anybody out there
with suggestions and/or wanting to write an article? --Editor)
</I> </blockquote>
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Sun, 01 Dec 1996 00:20:12 +1000 <BR>
Subject: <B> Quilting and geometry </B> <BR>
From: Chris Hennessy, <A HREF="mailto:chenness@enterprise.powerup.com.au">
chenness@enterprise.powerup.com.au </A>
<P>
I liked your comment about quilting being an interest. We tend to forget
that people have interests outside of computers in general (and linux in
particular).
<P>
Just like to say thanks for what is obviously an enormous effort you are
putting into the gazette. I'm new(ish) to linux and I find it a great
resource, not to say entertaining.
<P>
Has anyone suggested an article on the use of Xresources? As I said I'm
fairly new and find this a bit confusing... maybe someone would be
interested in an example or three?
<P>
Oh and with the quilting and geometry ... better make sure its not the
80x25+1-1 variety.
<blockquote> <I>
(Thanks, LG is a lot of work, as well as a lot of fun. And yes, I do have
a life outside of Linux. Anyone interested in writing about Xresources?
Thanks for writing. It's always nice to know we are attracting new readers.
--Editor) </I> </blockquote>
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Wed, 4 Dec 1996 13:33:26 +0200 (EET) <BR>
Subject: <B> security issue! </B> <BR>
From: Arto Repola, <A HREF="mailto:arepola@raahenet.ratol.fi">
arepola@raahenet.ratol.fi </A><BR>
<P>
Hi there!
<P>
I was wondering that could you write in some Gazette
something about Linux security...how to improve it,
how to setup firewall,shadow password systems etc?
<P>
I'm considering to build up my own linux-server and
i really would like to make it as secure as possible!
<P>
Nothing more this time!
<P>
http://raahenet.ratol.fi/~arepola
<blockquote> <I>
(And another great idea for an article. Any takers? --Editor)
</I> </blockquote>
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Wed, 04 Dec 1996 08:08:06 -0700 <BR>
Subject: <B> Reader Response </B> <BR>
From: James Cannon, <A HREF="mailto:cannonj@jads.kirtland.af.mil">
cannonj@jads.kirtland.af.mil </A><BR>
Organization: JADS JTF <BR>
<P>
Great Resource,
<P>
I really like the resource Linux offers new users. I have already
applied a few tricks to my PC. I wish some one would explain how to use
the GNU C/C++ compiler with Linux. It is a tool resting in my hard
drive. With commercial compilers, there is a programming environment
that links libraries automatically. Are there any tricks to command line
C/C++ programming with Linux?? Stay online!
<P>
James Cannon
<blockquote> <I>
(Thanks for the tip. Online is the best place to be. Anyone out there
got some C++ help for this guy? --Editor)
</I> </blockquote>
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Mon, 9 Dec 1996 23:27:21 +0000 (GMT) <BR>
Subject: <B> Linux InfraRed Support </B> <BR>
From: Hong Kim, <A HREF="mailto:kimh@domp04.adm.intelsat.int">
kimh@domp04.adm.intelsat.int </A> <BR>
<P>
Hi,
<P>
I have been so far unsuccessful in finding information for InfraRed
support on Linux.
<P>
I am particularly interested in hooking up Caldera Linux on a Thinkpad 560
using Extended Systems JetEye Net Plus. Caldera on Thinkpad I can handle
but the JetEye allows connection to ethernet or token ring networks via IR.
<P>
My searches of Linux Resources page come up negative.
I have posted to USENET and also emailed any web master that has any mention
of ThinkPad or IR on their pages. Still no answer.
<P>
Can you help me to find information. If I am successful, I would be
willing to write an article about it.
<P>
Hong
<blockquote> <I>
(I have sent your question on to Linux Journal's Tech Support Column.
Answers from this source can be slow as author contacts companys
involved. Sounds like you have covered all the bases in your search --
can anyone out there help him?
If you write the article, I'll be happy to post it in the LG so next
person who needs this information will have a quicker answer. --Editor)
</I> </blockquote>
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Thu, 5 Dec 96 13:00:01 MET <BR>
Subject: <B> Linux networking problem ...</B> <BR>
From: <A HREF="mailto:Tauche%fbm%mfh@mfhdvzis.mfh-iserlohn.de">
Tauche%fbm%mfh@mfhdvzis.mfh-iserlohn.de </A> <BR>
<P>
Hi there,
<P>
First I have to apologize for writing to this address with my problem, but I
don't no where to search for an answer and university's network is so
damned slow that surfing through the net searching for an answer makes no fun.
Another reason is that I've got no access to Usenet... means can't post in
comp.os.linux.networking... 8-((
<P>
I tried to find a news server near to Germany which allows posting without
using that damned -> identd <- but found none, may be you know where to find
a list with (free) news servers ?
<P>
Here's the problem: <BR>
I want to setup Linux in our University's LAN but ran into problems, because
the LAN is VINES-IP based so that normal TCP/IP packet drivers won't work.
The admin says I do need a driver which can tunnel the normal Linux TCP/IP
packets into those VINES-IP packets, so that they can be send over the LAN to
that box which has Internet connection....
<P>
Maybe you know if such thing is available and/or where I can get it.
Or maybe you can give some Email-addresses for asking people which real
knowledge 'bout Linux (maybe even that of Linus T. himself) and it's drivers.
<P>
Hope you can help me 8-))
<P>
Thanks in advantage <BR>
Stefan 8-))
<blockquote> <I>
(I've sent your problem on to Linux Journal's Technical Support column
and will post it in Linux Gazette's Mailbag next month. Neither one
will give you a fast answer.
<P>
I did a search of LG, LJ and SSC's Linux Resources using VINES as the
keyword. I found only one entry from an author's biography. It's old --
March 1995 -- and the guy was in the marine corp then so may or may not
be a good address. Anyway here's what it said:<BR>
&quot;Jon Frievald ... manages Wide Area Network running Banyan VINES. ...
e-mail to jaf@jaflrn.liii.com&quot;
<P>
Anyway you might give him a try for help ideas.
<P>
For faster access to LG have you tried any of LG's mirror sites in
Germany:
<ul>
<li><A HREF="http://www.cs.uni-dusseldorf.de/~stein/lg">
http://www.cs.uni-dusseldorf.de/~stein/lg </A>
<li><A HREF="http://vina12.va.htw-dresden.de/lg">
http://vina12.va.htw-dresden.de/lg </A>
<li><A HREF="http://www.fokus.gmd.de/linux/lg">
http://www.fokus.gmd.de/linux/lg </A>
</ul>
<P>
Please note that mirror sites wont help search time -- all searching is done
on SSC site. --Editor)
</I> </blockquote>
<a name="gen"><p></a>
<P> <hr> <P>
<!-- =================================================================== -->
<center><H3> General Mail </H3></center>
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Sat, 30 Nov 1996 20:35:17 -0600 (CST)<BR>
Subject: <B> Re: Slang Applications for Linux </B> <BR>
From: Duncan Hill, <A HREF="mailto:dhill@sunbeach.net">dhill@sunbeach.net</A><BR>
To: Larry Ayers, <A HREF="mailto:layers@vax2.rain.gen.mo.us">
layers@vax2.rain.gen.mo.us </A> <BR>
<P>
On Sat, 30 Nov 1996, Duncan Hill wrote:
<P>
Greetings. I was reading your article in the Linux Gazette, and thought
you might be interested to know that Lynx also has its own web site now at: <BR>
<A HREF="http://lynx.browser.org/">http://lynx.browser.org/ </A> <BR>
It's up to version 2.6 now, and is rather nice, specially with slang
included :)
<P>
Duncan Hill, Student of the Barbados Community College
<blockquote> <I>
(Thanks for the tip! I really appreciate responses from readers;
confirms that there are really readers out there! --Larry Ayers)
</I> </blockquote>
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Sat, 30 Nov 96 16:42:58 0200 <BR>
Subject: <B> Linux Gazette </B> <BR>
From: Paul Beard, <A HREF="mailto:paulb@id.co.zw">paulb@id.co.zw </A> <BR>
<P>
Hello from Zimbabwe.
<P>
Very nice production. Keep up the good work.
<P>
Regards, <BR>
Paul Beard.
<blockquote> <I>
(Thanks. --Editor) </I> </blockquote>
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Thu, 28 Nov 1996 23:54:38 +0000 <BR>
Subject: <B> Thanks! </B> <BR>
From: Russ Spooner, <A HREF="mailto:russ1@rmplc.co.uk">russ1@rmplc.co.uk </A><BR>
Organization: Kontagx <BR>
<P>
Hi, <BR>
I have been an avid reader of Linux Gazette since its inception!
I would just like to say that it has helped me a lot and that I am
really glad that it has become more regular :-)
<P>
The Image you have developed now has come a long way and it is now one
of the best organized sites I visit!
<P>
Also I would like to thank you for the link to my site :-) it was a real
surprise to "see myself up in lights" :)
<P>
Best regards!<BR>
Russ Spooner, http://www.pssltd.co.uk/kontagx
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Thu, 28 Nov 1996 12:49:12 -0500 <BR>
Subject: <B> LG Width </B> <BR>
From: frank haynes, <A HREF="mailto:frank@vatmom.com">frank@vatmom.com </A><BR>
Organization: The Vatmom Organization <BR>
<P>
Re: LG page width complaint, LG looks great here, and I don't think my window
is particularly large. Keep up the fine work.
<P>
--Frank, http://www.mindspring.com/~fmh
<blockquote> <I> (Good to hear. --Editor) </I> </blockquote>
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Fri, 29 Nov 1996 10:30:32 +0000 <BR>
Subject: <B> LG #12 </B> <BR>
From: Adam D. Moss. <A
HREF="mailto:adam@uunet.pipex.com">adam@uunet.pipex.com</A><BR>
<P>
Nice job on the Gazette, as usual. :)
<P>
Adam D. Moss / Consulting
<blockquote> <I>
( :-) --Editor) </I> </blockquote>
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Tue, 3 Dec 1996 12:55:18 -0800 (PST) <BR>
Subject: <B> Re: images in tcsh article </B> <BR>
From: Scott Call, <A HREF="mailto:scall@ccnet.com">scall@ccnet.com</A><BR>
<P>
Most of the images in the TCSH article in issue 12 are broken
<P>
-Scott
<blockquote> <I>
(You must be looking at one of the mirror sites. I inadvertently left
those images out of the issue12 tar file that I made for the mirror
sites. When I discovered it yesterday, I made an update file for the
mirrors. Unfortunately, I have found that not all the mirrors are
willing to update LG more than once a month, so my mistakes remain
until the next month. Sorry for the inconvenience and thanks for writing.
--Editor) </I> </blockquote>
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Fri, 06 Dec 1996 21:21:00 +0600 <BR>
Subject: <B> 12? why can you make so bad distributive????????????? </B><BR>
From: Sergey A. Panskih, <A HREF="mailto:serg@cnti.chel.su">serg@cnti.chel.su</A><BR>
<P>
i ftpgeted lg12 and untar.gz it as made with lg11.
lg11 was read as is: with graphics and so, but lg12... all graphics was
loosed.
i've verified hrefs and found out that href was written with principial
errors : i must copy all it to /images in my httpd server!!!!
<P>
this a pre-alpha version!!!
<P>
i can't do so unfixed products!!!
<P>
i'm sorry, but you forgotten how make a http-ready distrbutions... :)
<P>
Sergey Panskih
<P>
P.S. email me if i'm not true.
<blockquote> <I>
(I'm having a little trouble with your English and don't quite understand
what &quot;all graphics was loosed&quot; means. You shouldn't have to copy anything
anywhere: what are you copying to /images?
<P>
There is one problem I had that may apply to you. Are you throwing away
previous issues and only getting the current one? If so, I apologize
most humbly. I was not aware until this month that people were doing this
and when I made the tar file I included only new files and those that had
been changed since the last month. To correct this problem I put a new
tar file on the ftp site called standard_gifs.html. It's not that I've
forgotten how to make http-ready distributions, it's that I'm just learning
all the complexities. In the future I will make the tar file to include
all files needed for the current single issue, whether they were changed
or not.
<P>
I am very sorry to have caused you such problems and distress. --Editor)
</I> </blockquote>
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Mon, 02 Dec 96 18:13:48 <BR>
Subject: <B> spiral trashes letters </B> <BR>
From: <A HREF="mailto:jep@jephill.com">jep@jephill.com </A><BR>
<P>
It's clever and pretty, but the spiral notebook graphic still trashes the
left edge of letters printed in the issue 12 Mailbag.
<P>
Problem occurs using OS/2's Web Explorer version 1.2 (comes with OS/2 Warp 4.0).
Problem does NOT occur using Netscape 2.02 for OS/2 beta 2 (the latest beta
for OS/2).
<P>
Problem occurs even while accessing www.ssc.com/lg
<P>
Jep Hill
<blockquote> <I>
(Problem will always occur with versions of either Microsoft Explorer or
Netscape before 2.0. It is caused by a bug in TABLES that was fixed in
the 2.0 versions. I don't have access to OS/2's Web Explorer, so I can
only guess that it's the same problem. I'd recommend always using the latest
version of your browser. --Editor)
</I> </blockquote>
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date Mon, 9 Dec 1996 10:14:04 -0800 PST <BR>
Subject: <B> Background </B> <BR>
From: <A HREF="mailto:rayvd@shocking.com">rayvd@shocking.com </A> <BR>
<P>
I run at a resolution of 1152x846 (a bit odd I suppose) and although the
Gazette pages look very nice indeed, it is a bit hard to read when I
have my Netscape window maximized. The bindings part of the background
seems to be optimized for a width of 1024 and thus tiles over again on
the right side of the page. This makes reading a bit difficult as some
of the text now overlaps the bindings on the far right.
<P>
I'm not sure if that's a great description of the problem, but I can
easily make you a screenshot if you want to see what I mean.
<P>
Anyhow, this is only a minor annoyance--certainly one I'm willing to
live with in order to read your great 'zine. :)
<P>
Ray Van Dolson -=-=- Bludgeon Creations (Web Design) - DALnet #Bludgeon
-- http://www.shocking.com/~rayvd/
<blockquote> <I>
(Screen shot wont be necessary. When the web master first put the spiral
out there, the same thing happened to me -- I use a large window too, but not as large
as yours. He was able to expand it to fix it at that time. I notified him of
your problem, but not sure if he can expand it even more or not. We'll see.
Glad it's a problem you can live with. :-) --Editor)
</I> </blockquote>
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Sat, 7 Dec 1996 22:16:55 +0100 (MET) <BR>
Subject: <B> Problem with Printing.</B> <BR>
From: <A HREF="mailto:fm@M1.whitespace.de">fm@M1.whitespace.de</A><BR>
<P>
Hi,
<P>
This is just to let you people know, that there might be a slight problem.
I want to point out and make it perfectly clear that this is NOT a
complaint. I feel perfectly satisfied with the Linux Gazette as it is.
<P>
However sometimes I prefer to have a printed copy to take with me.
Therefore I used to print the LG. from Netscape. I'm using the new 3.1
version now. With the last two issues I have difficulties doing so.
All the pages with this new nice look don't print too well. The graphics
show up at all the wrong places and only one page is printed on the paper.
The rest is swallowed. Did you ever try to print it?
<P>
I had to use an ancient copy of Mosaic, that doesn't know anything about
tables, to print these pages. They don't look too good this way too, and
never did. I know this old Mosaic is buggy. At least it doesn't swallow
half of the stuff. This could as well be a bug in Netscape.
I know next to nothing about html.
<P>
Anyway, have fun.<BR>
Regards Friedhelm
<blockquote> <I>
(No, I don't try to print it, but will look into it. Are you printing out
&quot;TWDT&quot; from the TOC or trying to do it page by page?
It is out there in multi-file format and so if you print from say the Front Page,
the front page is all you'll get. &quot;TWDT&quot; is one single file
containing the whole issue, and the spiral and table stuff are removed so it
should print out for you okay. Let me know if this is already what you are
printing, so I'll know where to look for the problem. --Editor)
</I> </blockquote>
<p><HR> <p>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Wed, 18 Dec 1996 04:02:37 +0200 <br>
Subject: <b> Greetings </b><br>
From: Trucza Csaba, ctrucza@cemc.soroscj.roi <br>
To: fiskjm@ctrvax.Vanderbilt.Edu <br>
<p>
Well, Hi there!
<p>
Amazing. I've just read the Linux Gazette from the first issue to this
one, the 12th (actually I read just the first 7 issues through, because
the others were not downloaded correctly).
<p>
It's 4 in the morning and I'm enthusiastic. I knew Linux was good, I'm
using it for a year (this is because of the lack of my english grammar,
I mean the previous sentence, well...), so I knew it was good, but I
didn't expect to see something so nice like this Gazette.
<p>
It's good to see that there are a WHOLE LOT of people with huge will to
share.
<p>
I think we owe You a lot of thanks for starting it.
<p>
Merry Christmas, a Happy New Year, and keep it up!
<p>
Trucza Csaba, Romania
<blockquote><i>
(Thanks, I will. -- Editor)
</i></blockquote>
<p><HR> <p>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Mon, 23 Dec 1996 12:16:30 -0800 (PST) <br>
Subject: <b> lg issue 12 via ftp?</b><br>
From: schwarz@monet.m.isar.de (Christian Schwarz)
<p>
I just saw that issue #12 is out and accessible via WWW, but I can't find
the file on your ftp server nor on any mirrors.
<blockquote><i>
(Sorry for the problems. We changed web servers and I went on vacation.
Somehow in the web server change, some of the December files got left
behind. I didn't realize until today that this had happened.
Sorry for the inconvenience. --Editor)
</i></blockquote>
<p><HR> <p>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Fri, 20 Dec 1996 00:31:45 -0500 <br>
Subject: <b> Great IDEA </b><br>
From: Pedro A Cruz, pcruz@panixc.com <br>
<p>
Hi:
<p>
I visited your site recently and was astounded by the wealth of
information there.
I have lots of bandwidth to read your site. I noticed that you have
issues for download.
I Think it will be a great service to the LINUX community if you consider
publishing a CDROM (maybe from walnut creek cdrom) as a subscription
item.
<p>
pedro
<blockquote><i>
(Yes, that is a good idea. I'll talk to my publisher about it. --Editor)
</i></blockquote>
<p><HR> <p>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Sun, 22 Dec 1996 20:24:51 -0600 <br>
Subject: <b>Linux as router </b><br>
From: Robert Binz, rbinz@swconnect.net <br>
<p>
I have found myself trying to learn how to use Linux as a usenet server
to provide news feeds to people, and to use Linux as a IRC server.
Information on these topics are hard to come buy. If you have any
sources on these subjects that you can point me to I would be most
appreciative.
<p>
But any how, I have found an article in SysAdmin (Jan 96 (5.1)) that is
titled Using Linux as a Router, by johnathon Feldman. Is it possible to
reprint this article or get the author to write a new one for you?
<p>
TIA <br>
Robert Binz
<blockquote><i>
(I'll look into it. In the meantime, I've forwarded your letter to a guy I
think may be able to help you. --Editor)
</i></blockquote>
<p><HR> <p>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Fri, 13 Dec 1996 03:57:09 -0500 (EST)<BR>
Subject: <B> Correction for LG #12 </B> <BR>
From: Joe Hohertz, jhohertz@golden.net <BR>
Organization: Golden Triangle On-Line
<P>
Noticed the folowing in the News section.
<P>
A couple of new Linux Resources sites:
<blockquote> <I>
(Seems I had Joe's address wrong. Sorry. --Editor)
</I> </blockquote>
<p><HR> <p>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Tue, 17 Dec 1996 01:19:43 -0500 <br>
Subject: <b> One-shot downloads </b><br>
From: David M. Razler, david.razler@postoffice.worldnet.att.net
<p>
Folks:
<p>
While I realize that the economies of the LINUX biz require that there
be some method of making money even on the distribution of free and
"free" software, I have a request for them of us who 1) are currently
scraping for the cash for our Internet accounts and 2) would like to try
LINUX.
<p>
How about a one-shot download? I mean, oh, everything needed to
establish a LINUX system in one ZIP'ed (or tar/gz'd, though zip is a
more compatible format) file, one for each distribution?
<p>
I'm currently looking to establish LINUX on my "spare" PC, a 386DX-16
w/4 meg and a scavenged 2500MB IDE drive, etc. It will be relatively
slow, limited, lacks a CD-rom drive, but it's free, since the machine is
currently serving as a paperweight.
<p>
I could go out and buy a used CD-rom for the beast, or run a bastard
connection from my primary, indispensable work machine and buy the CDs.
But I am currently disabled and spending for these things has to be
weighed against other expenses (admittedly, I am certainly lucky and not
destitute, it would just be better)
<p>
I could get a web robot and download umpteen little files, puzzle them
out and put them together, though the load on your server would be
higher.
<p>
Or, under my proposed system, I could download Distribution Code,
Documents, and Major accessories in one group, then go back for the
individual bits and pieces I need to build my system.
<p>
Again, I realize that running your site costs money, and that people
make money, admirably little money, distributing LINUX on CDs, with the
big bucks (grin) of LINUX coming in non-free software, support and book
sales.
<p>
But if the system is to spread, providing a series of one-shot
downloads, possibly available only to individuals (I believe one could
copyright the *package* and require someone downloading to agree to use
it only on a single non-commercial system and not to redistribute, but I
am not an intellectual properties lawyer), to make life easier for them
of us who need to learn a UNIX-style system and build one on the cheap.
<p>
dmr
<!--====================================================================-->
<P> <hr> <P>
<A HREF="./index.html"><IMG SRC="../gx/indexnew.gif" ALT="[ TABLE OF
CONTENTS ]"></A>
<A HREF="../index.html"><IMG SRC="../gx/homenew.gif" ALT="[ FRONT
PAGE ]"></A>
<A HREF="lg_tips13.html"><IMG SRC="../gx/fwd.gif" ALT=" Next "></A>
<P>
<h5>This page written and maintained by the Editor of <I>Linux Gazette</I>,
<A HREF="mailto: gazette@ssc.com">gazette@ssc.com</A><BR>
Copyright &copy; 1997 Specialized Systems Consultants, Inc. </H5>
<P>
<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_tips13.html#free">Another 2cent Tip for LG</a>
<li><a HREF="./lg_tips13.html#console">Console Trick Follow-up</a>
<li><a HREF="./lg_tips13.html#gif">GIF Animations</a>
<li><a HREF="./lg_tips13.html#adm">How to close and reopen a new /var/adm/messages file</a>
<li><a HREF="./lg_tips13.html#admin">How to truncate /var/adm/messages</a>
<li><a HREF="./lg_tips13.html#infozip">Info-ZIP encryption code</a>
<li><a HREF="./lg_tips13.html#kernel">Kernel Compile Woes</a>
<li><a HREF="./lg_tips13.html#title">Letter 1 to LJ Editor re Titlebar</a>
<li><a HREF="./lg_tips13.html#more">Letter 2 to LJ Editor re Titlebar</a>
<li><a HREF="./lg_tips13.html#redial">PPP redialer script--A Quick Hack </a>
<li><a HREF="./lg_tips13.html#table">TABLE tags in HTML</a>
<li><a HREF="./lg_tips13.html#undelete">Text File undelete</a>
<li><a HREF="./lg_tips13.html#var">Truncating /var/adm/messages</a>
<li><a HREF="./lg_tips13.html#host">2c Host Trick</a>
<li><a HREF="./lg_tips13.html#tcsh">Use of TCSH's :e and :r Extensions</a>
<li><a HREF="./lg_tips13.html#notes">Various notes on 2c tips, Gazette 12</a>
<li><a HREF="./lg_tips13.html#howto">Viewing HOWTO Documents</a>
<li><a HREF="./lg_tips13.html#xaw">Xaw-XPM .Xresources troubleshooting tip</a>
<li><a HREF="./lg_tips13.html#xterm">Xterm Titlebar</a>
</ul>
<P> <hr> <P>
<!--================================================================-->
<a name="free"><p></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Another 2cent Script for LG
</H3>
Date: Wed, 11 Dec 1996 23:34:58 +0100 <BR>
From: Hans Zoebelein, <A HREF="mailto:zocki@goldfish.cube.net">
zocki@goldfish.cube.net</A><BR>
<P>
Hello LG people,
<P>
here comes a short script which will check from time to time
that there is enough free space available on anything
which shows up in mount (disks, cdrom, floppy...)
<P>
If space runs out, a message is printed every X seconds
to the screen and 1 mail message per filled device is fired up.
<P>
Enjoy! <BR>
Hans
<PRE>
#!/bin/sh
#
# $Id: issue13.html,v 1.3 2003/02/03 21:50:18 lg Exp $
#
#
# Since I got mysterious error messages during compile when
# tmp files filled up my disks, I wrote this to get a warning
# before disks are full.
#
# If this stuff saved your servers from exploding,
# send praising email to zocki@goldfish.cube.net.
# If your site burns down because of this, sorry but I
# warned you: no comps.
# If you really know how to handle sed, please forgive me :)
#
#
# Shoot and forget: Put 'check_hdspace &' in rc.local.
# Checks for free space on devices every $SLEEPTIME sec.
# You even might check your floppies or tape drives. :)
# If free space is below $MINFREE (kb), it will echo a warning
# and send one mail for each triggering device to $MAIL_TO_ME.
# If there is more free space than trigger limit again,
# mail action is also armed again.
#
# TODO: Different $MINFREE for each device.
# Free /*tmp dirs securely from old junk stuff if no more free space.
DEVICES='/dev/sda2 /dev/sda8 /dev/sda9' # device; your put disks here
MINFREE=20480 # kb; below this do warning
SLEEPTIME=10 # sec; sleep between checks
MAIL_TO_ME='root@localhost' # fool; to whom mail warning
# ------- no changes needed below this line (hopefully :) -------
MINMB=0
ISFREE=0
MAILED=""
let MINMB=$MINFREE/1024 # yep, we are strict :)
while [ 1 ]; do
DF="`/bin/df`"
for DEVICE in $DEVICES ; do
ISFREE=`echo $DF | sed s#.\*$DEVICE" "\*[0-9]\*" "\*[0-9]\*" "\*## | sed s#" ".\*##`
if [ $ISFREE -le $MINFREE ] ; then
let ISMB=$ISFREE/1024
echo "WARNING: $DEVICE only $ISMB mb free." >&2
#echo "more stuff here" >&2
echo -e "\a\a\a\a"
if [ -z "`echo $MAILED | grep -w $DEVICE`" ] ; then
echo "WARNING: $DEVICE only $ISMB mb free.
(Trigger is set to $MINMB mb)" \
| mail -s "WARNING: $DEVICE only $ISMB mb free!" $MAIL_TO_ME
MAILEDH="$MAILED $DEVICE"
MAILED=$MAILEDH
# put further action here like cleaning
# up */tmp dirs...
fi
elif [ -n "`echo $MAILED | grep -w $DEVICE`" ] ; then
# Remove mailed marker if enough disk space
# again. So we are ready for new mailing action.
MAILEDH="`echo $MAILED | sed s#$DEVICE##`"
MAILED=$MAILEDH
fi
done
sleep $SLEEPTIME
done
</PRE>
<P> <hr> <P>
<!--================================================================-->
<a name="console"><p></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Console Trick Follow-up
</H3>
Date: Wed, 27 Nov 1996 16:20:06 -0500 (EST)<BR>
From: Elliot Lee, <A HREF="mailto:sopwith@cuc.edu">sopwith@cuc.edu </A><BR>
<P>
Just finished reading issue #12, nice work.
<P>
A followup to the "Console Tricks" 2-cent tip: <BR>
What I like to do is have a line in /etc/syslog.conf that says:
<PRE>
*.* /dev/tty10
</PRE>
that sends all messages to VC 10, so I can know what's going on whether in
X or text mode. Very useful IMHO.
<P>
-- Elliot, http://www.redhat.com/
<P> <hr> <P>
<!--================================================================-->
<a name="gif"><p></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
GIF Animations
</H3>
Date: Thu, 28 Nov 1996 20:41:22 -0600 (CST) <BR>
From: Greg Roelofs, <A HREF="mailto:newt@pobox.com">newt@pobox.com </A>
<P>
I too thought WhirlGIF (Graphics Muse, issue 12) was the greatest thing
since sliced bread (well, aside from PNG) when I first discovered it, but
for creating animations, it's considerably inferior to Andy Wardley's
<A HREF="http://www.peritas.com/~abw/multigif.html">MultiGIF</A>. The
latter can specify tiny sprite images as parts of the animation, not just
full images. For my PNG-balls animation (see http://quest.jpl.nasa.gov/PNG/),
this resulted in well over a factor-of-two reduction in size (577k to 233k).
For another animation with a small, horizontally oscillating (Cylon eyes)
sprite, the savings was more than a factor of 20(!).
<P>
MultiGIF is available as source code, of course. (And I had nothing to do
with it, but I do find it darned handy.)
<P>
Regards, <BR>
Greg Roelofs, http://pobox.com/~newt/ <BR>
Newtware, Info-ZIP, PNG Group, U Chicago, Philips Research, ...
<P> <hr> <P>
<!--================================================================-->
<a name="adm"><p></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Re: How to close and reopen a new /var/adm/messages file
</H3>
Date: Thu, 05 Dec 1996 01:09:27 -0800 <BR>
From: CyberTech, <A HREF="mailto:CyberTech@ns.cybertech.org">CyberTech@ns.cybertech.org</A><BR>
<P>
Regarding the posting in issue #12 of your gazette, how to backup the
current messages file & recreate, here is an alternative method...
<P>
Place the lines at the end of this messages in a shell script
(/root/cron/swaplogs in this example). Don't forget to make it +x!
Execute it with 'sh scriptname', or by adding the following lines to
your (root's) crontab:
<PRE>
# Swap logfiles every day at 1 am, local time
0 01 * * * /root/cron/swaplogs
</PRE>
The advantage to this method over renaming the logfile and creating a
new one is that in this method, syslogd is not required to be restarted.
<PRE>
#!/bin/sh
cp /var/adm/messages /var/adm/messages.`date +%d-%m-%y_%T`
cat /dev/null >/var/adm/messages
cp /var/adm/syslog /var/adm/syslog.`date +%d-%m-%y_%T`
cat /dev/null >/var/adm/syslog
cp /var/adm/debug /var/adm/debug.`date +%d-%m-%y_%T`
cat /dev/null >/var/adm/debug
</PRE>
<P> <hr> <P>
<!--================================================================-->
<a name="admin"><p></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
How to truncate /var/adm/messages
</H3>
Date: Mon, 02 Dec 1996 16:47:20 +0100 <BR>
From: Eje Gustafsson, <A HREF="mailto:gne@ffa.se">gne@ffa.se </A> <BR>
<PRE>
>In answer to the question:
>
> What is the proper way to close and reopen a new >/var/adm/messages
> file from a running system?
>
> Step one: rename the file. Syslog will still be writing in it >after renaming so you don't
> lose messages. Step two: create a new one. After re-initializing >syslogd it will be used.
>just re-initialize.
>
> 1.mv /var/adm/messages /var/adm/messages.prev
> 2.touch /var/adm/messages
> 3.kill -1 pid-of-syslogd
>
> This should work on a decent Unix(like) system, and I know Linux >is one of them.
</PRE>
This is NOT an proper way of truncate /var/adm/messages.
<P>
It is better to do: <BR>
<ol>
<li>cp /var/adm/messages /var/adm/messages.prev
<li>&gt;/var/adm/messages or cp /dev/null /var/adm/messages
(both of them makes the file empty).
<li>No more.
</ol>
The problem is that when you remove the /var/adm/messages syslogd
gets confused and unhappy and you have to give syslogd a HUPSIG
but if you just sets the file length to zero without removing the file
syslogd don't complain. And if you are really unlucky your system
will go down because you didn't create /var/adm/messages quick enough
or forgot it.
<P>
Best of regards, <BR>
Eje Gustafsson, System Administrator <BR>
THE AERONAUTICAL RESEARCH INSTITUTE OF SWEDEN <BR>
<P> <hr> <P>
<!--================================================================-->
<a name="infozip"><p></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Info-ZIP encryption code
</H3>
Date: Thu, 28 Nov 1996 20:58:39 -0600 (CST) <BR>
From: Greg Roelofs, <A HREF="mailto:newt@pobox.com">newt@pobox.com</A><BR>
<P>
This is a relatively minor point, but Info-ZIP's Zip/UnZip encryption
code is *not* DES as reported in Robert Savage's article (LG issue 12).
It's actually considerably weaker, so much so that Paul Kocher has pub-
lished a known-plaintext attack (the existence of which is undoubtedly
the reason PKWARE was granted an export license for the code). While
the encryption is good enough to keep your mom and probably your boss
from reading your files, those who desire *real* security should look
to PGP (which is also based on Info-ZIP code, but only for compression).
<P>
And while I'm at it, Linux users will be happy to learn that the upcoming
releases of UnZip 5.3 and Zip 2.2 will be noticeably faster than the cur-
rent publicly released code. In Zip's case this is due to a work-around
for a gcc bug that prevented a key assembler routine from being used--Zip
is now 30-40% faster on large files. In UnZip's case the improvement is
due to a couple of things, one of which is simply better-optimized CRC
code. UnZip 5.3 is about 10-20% faster than 5.2, I believe. The new ver-
sions should be released in early January, if all goes well. And then...
we start working on multi-part archives. :-)
<P>
Greg Roelofs, http://pobox.com/~newt/ <BR>
Newtware, Info-ZIP, PNG Group, U Chicago, Philips Research, ...
<P> <hr> <P>
<!--================================================================-->
<a name="kernel"><p></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Kernel Compile Woes
</H3>
Date: Mon, 2 Dec 1996 21:35:29 +0400 (GMT-4)<BR>
From: Duncan Hill, <A HREF="mailto:dhill@sunbeach.net">dhill@sunbeach.net</A><BR>
<P>
Greetings. Having been through hell after a recompile of my kernel, I
thought I'd pass this on.
<P>
It all started with me compiling a kernel for JAVA binary support..who
tell me do that. Somehow I think I got experimental code in..even worse :>
Anyway, it resulted in a crash, and I couldn't recompile since then.
<P>
Well, after several cries for help, and trying all sorts of stuff, I
upgraded binutils to 2.7.0.3, and told the kernel to build elf support and
in elf format, and hey presto. I'd been wrestling with the problem for
well over a week, and every time, I'd get an error. Unfortunately, I had
to take out sound support, so I'm going to see if it'll add back in.
<P>
I have to say thank you to the folks on the linux-kernel mailing list at
vger.rutgers.edu. I posted there once, and had back at least 5 replies in
an hour. (One came back in 10 minutes).
<P>
As for the LG, it looks very nice seen thru Lynx 2-6 (no graphics to get
messed up :>) I love the Weekend Mechanic, and the 2 cent tips mainly.
Perhaps one day I'll contribute something,.
<P>
Duncan Hill, Student of the Barbados Community College
http://www.sunbeach.net/personal/dhill/dhill.htm
http://www.sunbeach.net/personal/dhill/lynx/lynx-main.html
<p><hr><p>
<!--================================================================-->
<a name="title"><p></a>
<h3><img align=bottom alt=" " src="../gx/lil2cent.gif">
Letter 1 to the LJ Editor re Titlebar
</h3>
Date: Sat, 21 Dec 1996 15:18:01 -0600 <br>
From: Roger Booth, <a
href="mailto:Roger_Booth@crow.bmc.com">Roger_Booth@crow.bmc.com</a><br>
To: linux@ssc.com
The Jan97 Issue 33 of <i>Linux Journal</i> contained the "Linux Gazette Two
Cent Tips".
I was interested in the tip "X Term Titlebar Function". Although
the text of the tip stated that the tip would work in ksh-based
systems, I could not get it to work as shown. I think there are
three problems. First, I think there are a few transcription
errors in the script. Second, I believe the author is using
embedded control characters and it was not obvious to me which
character sequences are representations of control characters
and which characters should be typed verbatim. Third, the
author uses a command-line option to the echo command which
is not available on all Unix platforms.
<p>
I finally used the following script:
<pre>
if [ ${SHELL##/*/} = "ksh" ] ; then
if [[ $TERM = x"term" ]] ; then
HOSTNAME=`uname -n`
label () { echo "\\033]2;$*\\007\\c"; }
alias stripe='label $LOGNAME on $HOSTNAME - ${PWD#$HOME/}'
cds () { "cd" $*; eval stripe; }
alias cd=cds
eval stripe
fi
fi
</pre>
I don't use vi, so I left out that functionality.
<p>
The functional changes I made are all in the arguments to the
echo command. The changes are to use \\033 rather than what
was shown in the original tip as ^[, to use \\007 rather than
^G, and to terminate the string with \\c rather than use the
option -n.
<p>
On AIX 4.1, the command &quot;echo -n hi&quot; echoes &quot;-n hi&quot;; in
other
words, -n is not a portable command-line option to the echo
command. I tested the above script on AIX 3.2, AIX 4.1,
HPUX 9.0, HPUX 10.0, Solaris 2.4 and Solaris 2.5. I'm still
trying to get Linux and my Wintel box mutually configured,
so I haven't tested it on Linux.
<p>
I have noticed a problem with this script. I use the rlogin
command to log in to a remote box. When I exit from the
remote box, the caption is not updated, and still shows the
hostname and path that was valid just before I exited. I tried
adding
<pre>
exits () { "exit" $*; eval stripe; }
alias exit=exits
</pre>
and
<pre>
rlogins () { "rlogin" $*; eval stripe; }
alias rlogin=rlogins
</pre>
Neither addition updated the caption to the host/path
returned to. Any suggestions?
<p>
Roger Booth, rbooth@bmc.com
<p><hr><p>
<!--================================================================-->
<a name="more"><p></a>
<h3><img align=bottom alt=" " src="../gx/lil2cent.gif">
Letter 2 to the LJ Editor re Titlebar
</h3>
Date: Fri, 13 Dec 1996 23:03:37 -0700 (MST)
From: Gary Masters, <A HREF="mailto:gmasters@csn.net">gmasters@csn.net</A><BR>
<P>
Some further clarification is needed with respect to the X Term Titlebar
Function tip in the Linux Gazette Two Cent Tips column of the January
1997 issue. With regard to the -print option to find, Michael Hammel
says, &quot;Linux does require this.&quot; This is yet another example of &quot;Your
mileage may vary.&quot; Some versions of Linux do not require the -print
option. And, although Solaris may not, SunOS 4.1.3_U1 and 4.1.4 do
require the -print option. Also, if running csh or tcsh, remember to
escape wildcards in the file specification ( e.g. find ./ -name \*txt\* )
so that the shell doesn't attempt to expand them.
<P>
Second, for those tcsh fans out there, here is an xterm title bar function
for tcsh.
<P>
NOTE: This works on Slackware 3.0 with tcsh version 6.04.00, under the
tab, fv, and OpenLook window managers. Your mileage may vary.
<pre>
if ( $TERM == xterm ) then
set prompt="%h> "
alias cwdcmd 'echo -n "^[]2;`whoami` on ${HOST} - $cwd^G^[]1;${HOST}^G"'
alias vi 'echo -n "^[]2;${HOST} - editing file-> \!*^G" ; vim \!* ;
cwdcmd'
alias telnet '/bin/telnet \!* ; cwdcmd'
alias rlogin '/usr/bin/rlogin \!* ; cwdcmd'
cwdcmd
else
set prompt="[%m]%~% "
endif
</PRE>
<ol>
<li>Check to see if tcsh is running in an xterm.
<li>Set the prompt to show the current history event number.
<li>Set the alias cwdcmd to display the user, host, and current path in
the xterm title bar, and set the icon name to the host name. cwdcmd
is a special tcsh alias, which if set holds a command that will be
executed after changing the value of $cwd.
<li>Set a vi alias to display the user, host, and file name under edit in
the xterm title bar. And run cwdcmd on exit to restore the xterm
title bar and icon name.
<li>Alias telnet and rlogin to restore the xterm title bar and icon name
upon exit. NOTE: Paths to telnet and rlogin may vary.
<li>Run the alias cwdcmd to set the initial xterm title bar and icon name.
<li>If this wasn't an xterm, set the prompt to show hostname and path.
</ul>
Gary Masters
<P> <hr> <P>
<!--================================================================-->
<a name="redial"><p></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
PPP redialer script--A Quick Hack
</H3>
Date: Sun, 08 Dec 1996 13:20:25 +0200 <BR>
From: Markku J. Salama, <A
HREF="mailto:msalama@usa.net">msalama@usa.net</A><BR>
<P>
This here is the way I do it, but don't use it if your area has some
regulations
about redialing the same phone numbers over and over:
<PRE>
#!/bin/sh
# A quick hack for redialing with ppp by <root@superfly.salama.fi>
# Tries 2 numbers sequentially until connected
# Takes 1 cmdline parm, the interface (ppp0, ppp1...)
# You need 2 copies of the ppp-on script (here called modemon{1,2}) with
# different telephone numbers for the ISP. These scripts should be
slightly
# customized so that the passwd is _not_ written in them, but is taken
# separately from the user in the main (a.k.a. this) script.
# Here's how (from the customized ppp-on a.k.a. modemon1):
# ...
# TELEPHONE=your.isp.number1 # Then make a copy of this script ->
modemon2
# and change this to your.isp.number2
# ACCOUNT=your.account
# PASSWD=$1 # This gets the passwd from the main
script.
# ...
# /sbin/ifconfig must be user-executable for this hack to work.
wd1=1 # counter start
stty -echo # echo off
echo -n "Password: " # for the ISP
account
read wd2
stty echo # back on
echo
echo "Trying..."
echo 'ATE V1 M0 &K3 &C1 ^M' > /dev/modem # modem init,
# change as
needed
/usr/sbin/modemon1 $wd2 # first try
flag=1 # locked
while [ 1 ]; do # just keep on
going
if [ "$flag" = 1 ]; then # locked?
bar=$(ifconfig | grep -c $1) # check for a link
if [ "$bar" = 1 ]; then # connected?
echo "Connected!" # if so, then
exit 0 # get outta here
else
foo=$(ps ax) # already
running?
blaat=$(echo $foo | grep "/usr/sbin/pppd")
if [ "$blaat" = "" ]; then # if not, then
flag=0 # unset lock
fi
fi
else # no lock, ready
# to continue
wd1=$[wd1+1]
echo "Trying again... $wd1"
if [ $[wd1%2] = 1 ]; then # this modulo
test
/usr/sbin/modemon1 $wd2 # does the
switching
else # between the 2
numbers
/usr/sbin/modemon2 $wd2 # we are using
fi
flag=1 # locked again
fi
done # All done!
</PRE>
There. Customize as needed & be an excellent person. Ant DON'T break any
laws if redialing is illegal in your area!
<P>
Mark
<P> <hr> <P>
<!--================================================================-->
<a name="table"><p></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
TABLE tags in HTML
</H3>
Date: Fri, 20 Dec 1996 11:51:22 -0500 <BR>
From: Michael O'Keefe, <A HREF="mailto:Michael.OKeefe@LMC.Ericsson.SE">
Michael.OKeefe@LMC.Ericsson.SE </A> <BR>
Organization: Ericsson Research Canada <BR>
<P>
G'day,
<P>
Just browsing through the mailbox, and I noticed your reply to a user
about HTML standard compliance and long download times. You replied that
you use the spiral image (a common thing these days) inside a &lt;TABLE&gt;.
<P>
I hope you are aware that a browser cannot display any contents of a
&lt;TABLE&gt; until it has received the &lt;/TABLE&gt; tag (no matter what version
of any browser - it is a limitation of the HTML tag) because the browser
cannot run its algorithm until it has received all of the &lt;TR&gt; and
&lt;TD&gt; tags, and it can't be sure of that until the &lt;/TABLE&gt; linux-questions-only@ssc.comes
through. I have seen many complex sites, using many images (thankfully
they at least used the HEIGHT and WIDTH tags on those images to tell
the browser how big the image will be so it didn't have to download
it to find out) but still, putting it in a table nullifies much of the
speediness that users require.
<P>
A solution I often offer the HTML designers under me is to use a
&lt;DL&gt;&lt;DD&gt; combination. Though this doesn't technically fit the HTML DTD
(certain elements are not allowed in a &lt;DL&gt;) and I use an editor that
will not allow illegal HTML, so I can't do it myself (without going
via a backdoor - but that's bad quality in my opionion). The downside
of the this is of course that you don't know what sized FONT the user
has set on the browser, and the FONT size affects the indetation width
of the &lt;DD&gt; element. But if your spiral image is not too wide, then
that could be made a NULL factor. The plus to the &lt;DL&gt;&lt;DD&gt; is that the
page can be displayed instantly as it comes down (again..providing the
developer uses the HEIGHT and WIDTH attributes on *ALL* images so that
the browser doesn't have to pause it's display to get the image and work
out how to lay out around the image)
<p>
Michael O'Keefe
<P> <hr> <P>
<!--================================================================-->
<a name="undelete"><p></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Text File undelete
</H3>
Date: Sat, 7 Dec 1996 15:00:58 +1300 (NZDT) <BR>
From: Michael Hamilton, <A HREF="mailto:michael@actrix.gen.nz">
michael@actrix.gen.nz </A> <BR>
<P>
Here's a trick I've had to use a few times.
<P>
Desperate person's text file undelete.
<P>
If you accidentally remove a text file, for example, some email, or
the results of a late night programming session, all may not be lost.
If the file ever made it to disk, ie it was around for more than 30
seconds, its contents may still be in the disk partition.
<P>
You can use the grep command to search the raw disk partition for the
contents of file.
<P>
For example, recently, I accidentally deleted a piece of email.
So I immediately ceased any activity that could modify that partition:
in this case I just refrained from saving any files or doing any compiles
etc. On other occasions, I've actually gone to the trouble of bring the
system down to single user mode, and unmounted the filesystem.
<P>
I then used the egrep command on the disk partition: in my case the email
message was in /usr/local/home/michael/, so from the output from df,
I could see this was in /dev/hdb5
<PRE>
sputnik3:~ % df
Filesystem 1024-blocks Used Available Capacity Mounted on
/dev/hda3 18621 9759 7901 55% /
/dev/hdb3 308852 258443 34458 88% /usr
/dev/hdb5 466896 407062 35720 92% /usr/local
sputnik3:~ % su
Password:
[michael@sputnik3 michael]# egrep -50 'ftp.+COL' /dev/hdb5 > /tmp/x
</PRE>
Now I'm ultra careful when fooling around with disk partitions, so I
paused to make sure I understood the command syntax BEFORE pressing
return. In this case the email contained the word 'ftp' followed by
some text followed by the word 'COL'. The message was about 20 lines
long, so I used -50 to get all the lines around the phrase. In the
past I've used -3000 to make sure I got all the lines of some source
code. I directed the output from the egrep to a different disk
partition - this prevented it from over writing the message I was
looking for.
<P>
I then used strings to help me inspect the output
<PRE>
strings /tmp/x | less
</PRE>
Sure enough the email was in there.
<P>
This method can't be relied on, all, or some, of the disk space may
have already been re-used.
<P>
This trick is probably only useful on single user systems. On
multi-users systems with high disk activity, the space you free'ed up
may have already been reused. And most of use can't just rip the box
out from under our users when ever we need to recover a file.
<P>
On my home system this trick has come in handy on about three
occasions in the past few years - usually when I accidentally trash
some of the days work. If what I'm working survives to a point where
I feel I made significant progress, it get's backed up onto floppy, so
I haven't needed this trick very often.
<P>
Michael
<p><hr><p>
<!--================================================================-->
<a name="var"><p></a>
<h3><img align=bottom alt=" " src="../gx/lil2cent.gif">
Truncating /var/adm/messages
</h3>
Date: Tue, 31 Dec 1996 15:32:57 GMT+100 <BR>
From: Michel Vanaken, <A HREF="mailto:michel@idtech.be">michel@idtech.be</A><BR>
Organization: IDtech <BR>
<P>
Hi !
<P>
About the topic &quot;How to truncate /var/adm/messages&quot;, here's the way
to do it with a shell script :
<pre>
mv /var/adm/messages /var/adm/messages.prev
touch /var/adm/messages
mv /var/adm/syslog /var/adm/syslog.prev
touch /var/adm/syslog
kill -1 `ps x | grep syslog | grep -v grep | awk '{ print $1 }'`
</pre>
Happy new year ! <BR>
Michel
<P> <hr> <P>
<!--================================================================-->
<a name="host"><p></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
2c Host Trick
</H3>
Date: Tue, 10 Dec 1996 17:27:46 +0300 <BR>
From: Paul Makeev, <A HREF="mailto:mac@rosprint.ru">mac@rosprint.ru</A><BR>
<P>
In order to make DHCPD by ISC/Vixie to run under Linux, you should
have route to host 255.255.255.255. Standard "route" from Slackware
distribution does not like the string "route add -host 255.255.255.255
dev eth0". But you can add hostname to your /etc/hosts file with
address 255.255.255.255, and use "route add hostname dev eth0" instead.
It works.
<P>
Paul.
<P> <hr> <P>
<!--================================================================-->
<a name="tcsh"><p></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Use of TCSH's :e and :r Extensions
</H3>
Date: Mon, 02 Dec 1996 23:25:23 -0500 <BR>
From: Bill C. Riemers, <A HREF="mailto:bcr@feynman.com">bcr@feynman.com</A><BR>
<P>
I'd like to congratulate Jesper Pedersen on his article on tcsh
tricks. Tcsh has long been my favorite shell. But most of the features
Jesper hit upon are also found in bash. Tcsh's most useful and unique
features are its variable/history suffixes.
<P>
For example, if after applying a patch one wishes to undo things, by
moving the *.orig files to there base names, the :r extension which
means to strip the extension comes in handy. e.g.
<PRE>
foreach a ( *.orig )
mv $a $a:r
end
</PRE>
The same loop for ksh looks like:
<PRE>
for a in *.orig; do=20
mv $a `echo $a|sed -e 's,\.orig$,,g'`
done
</PRE>
Even better, one can use the :e extension to extract the file extension.
For example, lets say we we want to do the same thing on compressed
files:
<PRE>
foreach a ( *.orig.{gz,Z} )
mv $a $a:r:r.$a:e
end
</PRE>
The $a:r:r is the filename without .orig.gz and .orig.Z, we tack the
.gz or .Z back on with .$a:e.
<P>
Bill
<P> <hr> <P>
<!--================================================================-->
<a name="notes"><p></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Various notes on 2c tips, Gazette 12
</H3>
Date: Wed, 04 Dec 1996 15:30:21 -0600 <BR>
From: Justin Dossey, <A HREF="mailto:dossey@ou.edu">dossey@ou.edu </A> <BR>
<P>
I noticed a few overly difficult or unnecessary procedures recommended
in the 2c tips section of Issue 12. Since there is more than one, I'm
sending it to you:
<PRE>
#!/bin/sh
# lowerit
# convert all file names in the current directory to lower case
# only operates on plain files--does not change the name of
directories
# will ask for verification before overwriting an existing file
for x in `ls`
do
if [ ! -f $x ]; then
continue
fi
lc=`echo $x | tr '[A-Z]' '[a-z]'`
if [ $lc != $x ]; then
mv -i $x $lc
fi
done
</PRE>
Wow. That's a long script. I wouldn't write a script to do that;
instead, I would use this command:
<PRE>
for i in * ; do [ -f $i ] && mv -i $i `echo $i | tr '[A-Z]' '[a-z]'`;
done;
</PRE>
on the command line.
<P>
The contributor says he wrote the script how he did for
understandability (see below).
<P>
On the next tip, this one about adding and removing users, Geoff is
doing fine until that last step. Reboot? Boy, I hope he doesn't reboot
every time he removes a user. All you have to do is the first two
steps. What sort of processes would that user have going, anyway? An
irc bot? Killing the processes with a simple
<PRE>
kill -9 `ps -aux |grep ^<username> |tr -s " " |cut -d " " -f2`
</PRE>
Example, username is foo
<PRE>
kill -9 `ps -aux |grep ^foo |tr -s " " |cut -d " " -f2`
</PRE>
That taken care of, let us move to the forgotten root password.
<P>
The solution given in the Gazette is the most universal one, but not the
easiest one. With both LILO and loadlin, one may provide the boot
parameter &quot;single&quot; to boot directly into the default shell with no login
or password prompt. From there, one may change or remove any passwords
before typing ``init 3``to start multiuser mode.
Number of reboots: 1
The other way
Number of reboots: 2
<P>
That's just about it. Thanks for the great magazine and continuing
contribution to the Linux community. The Gazette is a needed element
for many linux users on the 'net.
<P>
Justin Dossey
<P>
Date: Wed, 4 Dec 1996 08:46:24 -0800 (PST) <BR>
Subject: <B> Re: lowerit shell script in the LG </B> <BR>
From: Phil Hughes, <A HREF="mailto:phil@ssc.com">philphiphil.com </A> <BR>
<P>
The amazing Justin Dossey wrote:
<PRE>
> #!/bin/sh
> for i in * ; do [ -f $i ] && mv -i $i `echo $i | tr '[A-Z]' '[a-z]'`;
> done;
>
> may be more cryptic than
...
>
> but it is a lot nicer to the system (speed & memory-wise) too.
</PRE>
Can't argue. If I had written it for what I considered a high usage
situation I would have done it more like you suggested. The intent,
however, was to make something that could be easily understood.
<P>
Phil Hughes
<p><hr><p>
<!--================================================================-->
<a name="howto"><p></a>
<h3><img align=bottom alt=" " src="../gx/lil2cent.gif">
Viewing HOWTO Documents
</h3>
Date: Sun, 22 Dec 1996 09:43:40 -0800 <br>
From: Didier Juges, <a
href="mailto:dj@destin.nfds.net">dj@destin.nfds.net</a><br>
<p>
>From a newbie to another, here is a short script that eases looking for
and viewing howto documents.
My howto's are in /usr/doc/faq/howto/ and are gzipped. The file names are
XXX-HOWTO.gz, XXX being the subject.
I created the following script called "howto" in the /usr/local/sbin
directory:
<pre>
#!/bin/sh
if [ "$1" = "" ]; then
ls /usr/doc/faq/howto | less
else
gunzip -c /usr/doc/faq/howto/$1-HOWTO.gz | less
fi
</pre>
When called without argument, it displays a directory of the available
howto's. Then when entered with the first part of the file name (before
the hyphen) as an argument, it unzips (keeping the original intact) then
displays the document.
<p>
For instance, to view the Serial-HOWTO.gz document, enter:
$ howto Serial
<p>
Keep up the good work.
<p>
Didier
<p><hr><p>
<!--================================================================-->
<a name="xaw"><p></a>
<h3><img align=bottom alt=" " src="../gx/lil2cent.gif">
Xaw-XPM .Xresources troubleshooting tip.
</h3>
Date: Wed, 18 Dec 1996 17:02:07 +0100 (GMT+0100) <br>
From: Robin Smidsroed, <a
href="mailto:dex@sysedata.no">dex@sysedata.no</a><br>
<p>
I'm sure a lot of you folks out there have installed the new Xaw-XPM and
like it a lot. But I've had some trouble with it. If I don't install the
supplied .Xresources-file, xcalc and some other apps (ghostview is one)
segfaults whenever you try to use them.
<p>
I found out that the entry which causes this, is this:
<pre>
*setPixmap: /path/to/an/xpm-file
</pre>
If this entry isn't in your .Xresources, xcalc and ghostview won't work. Hope
some of you out there need this.
<p>
And while you're at ghostview, remember to upgrade ghostscript to the latest
version to get the new and improved fonts, they certainly look better on
paper than the old versions.
<p>
Ciao! <br>
Robin
<p>
PS: Great mag, now I'm just waiting for the arrival of my copy of LJ
<p><hr><p>
<!--================================================================-->
<a name="xterm"><p></a>
<h3><img align=bottom alt=" " src="../gx/lil2cent.gif">
xterm title bar
</h3>
Date: Wed, 18 Dec 1996 21:21:47 -0800 (PST)
From: bradshaw@nlc.com (Lee Bradshaw)
<p>
Hi Guys,
<p>
I noticed the &quot;alias for cd xterm title bar tip&quot; from Michael
Hammel in
the <i>Linux Gazette</i> and wanted to offer a possible improvement for your
.bashrc file. A similar solution might work for ksh, but you may need
to substitute $HOSTNAME for \h, etc:
<pre>
if [ "x$TERM" = "xxterm" ]; then
PS1='\h \w-> \[\033]0;\h \w\007\]'
else
PS1='\h \w-> '
fi
</pre>
PS1 is an environment variable used in bash and ksh for storing the
normal prompt. \h and \w are shorthand for hostname and working
directory in bash. The \[ and \] strings enclose non-printing
characters from the prompt so that command line editing will work
correctly. The \O33]0; and \007 strings enclose a string which
xterm will use for the title bar and icon name. Sorry, I don't
remember the codes for setting these independently. (ksh users note:
\033 is octal for ESC and \007 is octal for CTRL-G.) This example just
changes the title bar and icon names to match the prompt before the
cursor.
<p>
Any program which changes the xterm title will cause inconsistencies if
you try an alias for cd instead of PS1. Consider rlogin to another
machine which changes the xterm title. When you quit rlogin, there is
nothing to force the xterm title back to the correct value when using
the cd alias (at least not until the next cd). This is not a problem
when using PS1.
<p>
You could still alias vi to change the xterm title bar, but it may not
always be correct. If you use ":e filename" to edit a new file, vi
will not update the xterm title. I would suggest upgrading to vim (VI
iMproved). It has many nice new features in addition to displaying the
current filename on the xterm title.
<p>
Hopefully this tip is a good starting point for some more experimenting.
Good luck!
<p>
Lee Bradshaw, bradshaw@nlc.com
<P> <hr> <P>
<!--================================================================-->
<A HREF="./index.html"><IMG SRC="../gx/indexnew.gif" ALT="[ TABLE OF
CONTENTS ]"></A> <A HREF="../index.html"><IMG SRC="../gx/homenew.gif"
ALT="[ FRONT PAGE ]"></A> <A HREF="lg_mail13.html"><IMG SRC="../gx/back2.gif" ALT=" Back "></A>
<A HREF="lg_bytes13.html"><IMG SRC="../gx/fwd.gif" ALT=" Next "></A>
<P> <hr> <P>
<h5>This page maintained by the Editor of <I>Linux Gazette</I>,
<A HREF="mailto: gazette@ssc.com">gazette@ssc.com</A><BR>
Copyright &copy; 1997 Specialized Systems Consultants, Inc. </H5>
<P>
<H4>&quot;Linux Gazette...<I>making Linux just a little more fun!</I>&quot;</H4>
<HR>
<center>
<table cellpadding=7><tr><td>
<IMG SRC="./gx/bytes2.gif" ALT="News Bytes">
</td><td>
<H3>Contents:</H3>
<ul>
<li><a HREF="./lg_bytes13.html#general">News in General</a>
<li><a HREF="./lg_bytes13.html#software">Software Announcements</a>
</ul>
</td></tr></table>
</center>
<a name="general"><p></a>
<p><hr><p>
<!-- =================================================================== -->
<center><H3> News in General </H3></center>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
SECURITY: (linux-alert) LSF Update#14: Vulnerability of the lpr program.
</H3>
<P>
Date: Sat, 26 Nov 1996 <BR>
Linux Security FAQ Update -- lpr Vulnerability <BR>
A vulnerability exists in the lpr program version 0.06. If installed
suid to root, the lpr program allows local users to gain access to a
super-user account.
<P>
Local users can gain root privileges. The exploits that exercise
this vulnerability were made available.
<P>
lpr utility from the lpr 0.06 suffers from the buffer overrun
problem. Installing lpr as a suid-to-root is needed to allow
print spooling.
<P>
This LSF Update is based on the information originally posted to
linux-security mailing list.
<P>
For additional information and distribution corrections: <BR>
Linux Security WWW: <A HREF="http://bach.cis.temple.edu/linux/linux-security">
http://bach.cis.temple.edu/linux/linux-security</A>
linux-security & linux-alert mailing list archives:
<A HREF="ftp://linux.nrao.edu/pub/linux/security/list-archive">
ftp://linux.nrao.edu/pub/linux/security/list-archive </A>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
LINUXEXPO '97 TECHNICAL CONFERENCE
</H3>
<P>
Durham, N.C. December 31,1996-- It was announced today that the third annual
LinuxExpo Technical Conference will be held at the N.C. Biotechnology Center
in Research Triangle Park, NC on April 4-5, 1997. The conference will consist
of fourteen elite developers who will give technical talks on various topics
all related to the development of Linux. This year the event is expected to
draw 1,000 attendees who will be coming not only for the conference, but to
visit the estimated 30 Linux companies and organizations that will be selling
their own Linux products and giving demonstrations. The event will also
include a Linux User's Group meeting, an install fair, and a job fair for all
of the computer programming hopefuls. LinuxExpo '97 will be complete with
refreshments and entertainment from the Class Action Jugglers.
<P>
For addtional information:
Anna Selvia, <A HREF="mailto:anna@linuxexpo.org">anna@linuxexpo.org </A><BR>
LinuxExpo '97 Technical Conference, <A
HREF="mailto:www.linuxexpo.org">www.linuxexpo.org</A><BR>
3201 Yorktown Ave. Suite 113 <BR>
Durham, NC 27713
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
WWW: Linux Archive Search Site
</H3>
<P>
Date: Thu, 21 Nov 1996 <BR>
Tired of searching sunsite or tsx-11 for some program you
heard about on irc? Well, the Linux Archive
Search (LAS) is here. It is a search engine that searches an updated database
of the files contained on sunsite.unc.edu, tsx-11.mit.edu,
ftp.funet.fi, and ftp.redhat.com. You can now quickly find out where
the files are hiding! The LAS is living at http://torgo.ml.org/las
(It may take a second to respond, its on a slow link). So give it a
whirl, who knows, you may use it a lot!
<P>
For additional information: <BR>
Jeff Trout, <A HREF="mailto:threshar@serve.com">threshar@serve.com </A> <BR>
The Internet Access Company, Inc.<BR>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
Netherlands - Linux Book On-line
</H3>
<P>
Date: Thu, 05 Dec 1996 <BR>
The very first book to appear in Holland on the Linux operating system
has gone on-line and can be found at:
<P>
<A HREF="http://www.cv.ruu.nl/~eric/linux/boek/">
http://www.cv.ruu.nl/~eric/linux/boek/</A>
<P>
And of course from every (paper) copy sold, one dollar is sent to the
Free Software Foundation.
For additional information: <BR>
Hans Paijmans, KUB-University, Tilburg, the Netherlands <BR>
<A HREF="mailto:paai@kub.nl">paai@kub.nl </A>,
<A HREF="http://purl.oclc.org/NET/PAAI/">http://purl.oclc.org/NET/PAAI/ </A>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
New O'Reilly Linux WWW Site
</H3>
Date: 26 Nov 1996 <BR>
<P>
Check out the new O'Reilly & Associates, Inc. Linux web
site at <A HREF="http://www.ora.com/info/linux/">http://www.ora.com/info/linux/ </A>
<P>
It has:
<ul>
<li>Free excerpt from Linux Multimedia Guide
<li>Interview with Olaf Kirch
<li>Recommended links to the best Linux web sites.
<li>Links to our Unix & Linux book pages
</ul>
For additional information: <BR>
O'Reilly & Associates, Inc., <A HREF="mailto:john@ora.com">john@ora.com </A>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
PCTV Reminder
</H3>
<P>
The "Unix III - Linux" show will air on the
Jones Computer Network (JCN) and the Mind Extension University Channel
(MEU) the week of January 20, 1997.
<P>
The scheduled times are:
<ul>
<li>Mon. 11:30 PM - 12:00 AM
<li>Wed. 9:30 PM - 10:00 PM
<li>Thu. 11:30 PM - 12:00 AM
<li>Fri. 9:30 PM - 10:00 PM
<li>Sun. 9:30 PM - 10:00 PM
</ul>
This show will also air on the NBC Superchannel (CNBC) January 25, 1997.
<P>
It is best to call your local cable operator to find the appropriate
channel.
<P>
Tom Schauer, Production Assoc. PCTV
<a name="software"><p></a>
<P> <hr> <P>
<!-- =================================================================== -->
<center><H3> Software Announcements </H3></center>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
daVinci V2.0.2 - Graph Visualization System
</H3>
<P>
November 20, 1996 (Bremen, Germany) - The University of Bremen announces
daVinci V2.0.2, the new edition of the noted visualization tool for
generating high-quality drawings of directed graphs with more than 2000
installations worldwide. Users in the commercial and educational domain
have already integrated daVinci as user interface for their application
programs to visualize hierarchies, dependency structures, networks,
configuration diagrams, dataflows, etc. daVinci combines hierarchical graph
layout with powerful interactive capabilities and an API for remote
access from a connected application. In daVinci V2.0.2, a few extensions
related to improving performance and usage of the previous V2.0.1 release
have been made based on user feedback.
<P>
daVinci V2.0.2 is licensed free of charge for non-profit use and is
immediately available Linux.
The daVinci system can be downloaded with this form:
<P>
<A HREF="http://www.informatik.uni-bremen.de/~davinci/daVinci_get_daVinci.html">
http://www.informatik.uni-bremen.de/~davinci/daVinci_get_daVinci.html </A>
<P>
For additional information: <BR>
Michael Froehlich, daVinci Graph Visualization Project <BR>
Computer Science Department, University of Bremen, Germany <BR>
<A HREF="http://www.informatik.uni-bremen.de/~davinci">
http://www.informatik.uni-bremen.de/~davinci </A>,
<A HREF="mailto:daVinci@Informatik.Uni-Bremen.DE">
daVinci@Informatik.Uni-Bremen.DE </A>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
WWW: getwww 1.3 - download an entire HTML source tree
</H3>
<P>
Date: Wed, 04 Dec 1996 <BR>
Getwww is designed to download an entire HTML source tree from a
remote URL, recursively changing image and hypertext links.
<P>
From the LSM: <BR>
Primary-site: ftp.kaist.ac.kr /incoming/www 25kB getwww++-1.3.tar.gz <BR>
Alternate-site: sunsite.unc.edu /pub/Linux/system/Network/info-systems/www
25kB getwww++-1.3.tar.gz <BR>
Platform: Linux-2.0.24 <BR>
Copying-policy: GPL <BR>
<P>
For additional information: <BR>
In-sung Kim, Network Tool Group, <A HREF="mailto:kisskiss@soback.kornet.nm.kr">
kisskiss@soback.kornet.nm.kr</A>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
Motif Interface Builder on Unifix 2.0
</H3>
<P>
Date: Sun, 01 Dec 1996 <BR>
Unifix Software GmbH is proud to announce View Designer/X, a new Motif
interface builder available for Linux. A demo version of VDX is included
on Unifix Linux 2.0.
<P>
With object oriented and interactive application development tools, the
software developer is able to design applications with better quality
and in shorter times.
<P>
For more information and to download the latest demo version, see:
<P>
<A HREF="http://www.unifix.de/products/vdx">
http://www.unifix.de/products/vdx </A>
<P>
For additional information:
Unifix Software GmbH, <A HREF="mailto:info@unifix.de">info@unifix.de </A>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
View Designer/X
</H3>
Date: Fri, 13 Dec 1996 <BR>
<P>
View Designer/X, a new Motif Interface Builder for Linux has been released.
It enables application developers to design user interfaces
with Motif 2.0 widgets and to generate C and C++ code. The VDX provides
an interactive Wysiwyg View and a Widget Tree Browser which can be used
to modify the structure of the user interface. All resources are
adjustable by Widget Resource Editor and by using template files the
code generation of VDX is more flexible than those of other interface
builders.
<P>
Bredex GmbH, Germany is distributing the View Designer/X via Web service.
Please see following web page for more information and downloading the
free demo version:
<P>
<A HREF="http://www.bredex.de/EN/vdx/">http://www.bredex.de/EN/vdx/</A>
<P>
Dirk Laessig, <A HREF="mailto:dirk@unifix.de">dirk@unifix.de</A>
<P> <hr> <P>
<!-- ===================================================================
-->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
X-Files 1.21 - graphical file manager in tcl/tk
</H3>
Date: Sun, 01 Dec 1996 <BR>
<P>
X-Files is a graphical file management program for Unix/X-Window
environment developed on Linux.
<P>
For more information and packages see:<BR>
<A HREF="http://pinhead.tky.hut.fi/~xf_adm/">http://pinhead.tky.hut.fi/~xf_adm/</A>
<A HREF="http://www.hut.fi/~mkivinie/xfindex.html">http://www.hut.fi/~mkivinie/xfindex.html</A>
<A
HREF="ftp://java.inf.tu-dresden.de/pub/unix/x-files/">ftp://java.inf.tu-dresden.de:/pub/unix/x-files/</A>
<P>
For questions: <BR>
<A HREF="mailto:xf_adm@pinhead.tky.hut.fi">xf_adm@pinhead.tky.hut.fi</A><BR>
<P>
For additional information: <BR>
Mikko Kiviniemi, <A HREF="mailto:mkivinie@cc.hut.fi">mkivinie@cc.hut.fi </A>,
<A HREF="mailto:jforsten@cc.hut.fi">jforsten@cc.hut.fi </A> <BR>
Helsinki University of Technology
<P> <HR> <P>
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<P><HR><P>
<h5>This page written and maintained by the Editor of <I>Linux Gazette</I>,
<A HREF="mailto: gazette@ssc.com">gazette@ssc.com</A><BR>
Copyright &copy; 1997 Specialized Systems Consultants, Inc. </H5>
<P>
</BODY>
</HTML>
<!-- ===================================================================== -->
<P> <hr> <P>
<H4>&quot;Linux Gazette...<I>making Linux just a little more fun!</I>
&quot;</H4>
<P> <hr> <P>
<!-- ===================================================================== -->
<center>
<H1><A NAME="answer">
<img src="../gx/ans.gif" alt="" border=0 align=middle>
The Answer Guy
<img src="../gx/ans.gif" alt="" border=0 align=middle>
</A></H1> <BR>
<H4>By James T. Dennis,
<a href="mailto:jimd@starshine.org">jimd@starshine.org</a> </H4>
</center>
<p><hr><p>
<H3>Contents:</H3>
<li><a HREF="./answer.html#dialup">Dialup Problem</a>
<li><a HREF="./answer.html#file">File Referencing</a>
<li><a HREF="./answer.html#modem">Combining Modems for More Speed</a>
<li><a HREF="./answer.html#server">WWW Server</a>
</ul>
<p><hr><p>
<!--================================================================-->
<a name="modem"><p></a>
<h3><img align=bottom alt=" " src="../gx/ques.gif">
Combining modems for more speed
</h3>
Date: Mon, 23 Dec 1996 23:37:00 -0800 (PST) <br>
From: liberty@pe.net (Keith) <br>
<p>
Thanks for reading this post. I have heard that it's possible to set up
Linux to combine two analog modems into one so as to double the speed of
a connection. Is this true, how does this work and where can I get more
info, guidance, how-to, etc.? I have Slackware 96 from Infomagic.
Your truly,
Keith Bell
<blockquote> <B>
I've heard of this as well. I've never used it but
let's look it up...
<p>
Ahh... that would be the EQL option in the kernel.
Here's an excerpt from the 'make menuconfig' help pages
(in the 2.0.27 kernel sources):
<p>
<b>Linux Kernel v2.0.27 Configuration</b>
<p>
EQL (serial line load balancing) support: <br>
If you have two serial connections to some other computer (this
usually requires two modems and two telephone lines) and you use
SLIP (= the protocol for sending internet traffic over telephone
lines) or PPP (= a better SLIP) on them, you can make them behave
has to be supported at the other end as well, either with a similar
EQL Linux driver or with a Livingston Portmaster 2e. Say Yes if you
want this and read drivers/net/README.eql.
<p>
So that file is : <br>
EQL Driver: Serial IP Load Balancing HOWTO <br>
Simon "Guru Aleph-Null" Janes, simon@ncm.com <br>
v1.1, February 27, 1995 <br>
<p>
(After reading this you'll know about as much on this subject
as I do -- after using any of this you'll know *much* more).
</B> </blockquote>
<p><hr><p>
<!--================================================================-->
<a name="dialup"><p></a>
<h3><img align=bottom alt=" " src="../gx/ques.gif">
Dialup Problem
</h3>
Date: Tue, 31 Dec 1996 05:13:51 -0800 (PST) <BR>
From: <A HREF="mailto:gekko@midusa.net">gekko@midusa.net</A><BR>
<P>
I don't know if you can, or even are willing, help me witha problem i
have. I'm running redhat 4.0, on a p120 w/24 megs of ram, kernel 2.0.18
<blockquote> <b>
I'm willing.
</b> </blockquote>
anyway...i have this ppp connection problem and no I know knows what the
problem is, i've looked through the FAQS, HOWTO's, tried #linux on irc,
etc etc...no one knows what my problem is, so now i'm desperate.
<P>
When i try to dial my isp, i get logged in fine, but its REALLY slow.
i'm using the 'network module' ppp thing in control panel on X.
mru=1500, asyncmap=0,speed=115000, i couldn't find a place to insert
mtu, and when i tried putting that in /etc/ppp/options the script this
program was using wouldn't work.
<blockquote> <B>
Usually I see these symptoms when there is an IRQ
conflict. Some of the data gets through -- with lots
of errors and lots of retransmits but any activity on the
rest of the machine -- or even just sitting there --
and you get really bad throughput and very unreliable
connections.
</B> </blockquote>
I noticed that after i input something and then move the cursor off of
the windows, it runs at a much faster speed, and it gets annoying moving
the cursor back and forth.
I tried dip, minicom, and this 'network module' thing...all are slow
<blockquote> <B>
I would do all of your troubleshooting from outside of
X. Just use the virtual consoles until everything else
works right. (Fewer layers of things to conflict with
one another).
</B> </blockquote>
if you can shed any light on this, it would be much appreciated.
thanks
<blockquote> <B>
Take a really thorough look at the hardware settings for
everything in the machine. Make a list of all the cards
and interfaces -- go through the docs for each one
and map out which ones are using which interfaces.
<P>
I ended up going through several combinations of
video cards and I/O cards before I got my main system
all integrated. Luckily newer systems are getting
better (this is a 386DX33 with 32Mb of RAM and a
2Mb video cards -- two IDE's, two floppy drives, two
SCSI hardisks, an internal CD-ROM, and external magneto
optical drive, a serial mouse, a modem (used for dial-in
dial-out, uucp, and ppp) and null modem (I hook a laptop
to it as a terminal for my wife) and an ethernet card.
<P>
Another thing to check is the cabling between your serial
connector and your modem. If you're configured for
XON/XOFF you're in trouble. If you're configured for
hardware flow control and you don't have the appropriate
wires in your cable than you're in worse trouble.
<P>
Troubleshooting of this sort really is best done over
voice or in person. There are too many steps to
the troubleshooting and testing to do effectively
via e-mail.
</B> </blockquote>
<p><hr><p>
<!--================================================================-->
<a name="file"><p></a>
<h3><img align=bottom alt=" " src="../gx/ques.gif">
File Referencing
</h3>
Date: Wed, 18 Dec 1996 00:16:42 -0800 (PST) <br>
<pre>
> "A month of sundays ago L.U.S.T List wrote:"
>> 1. I do not know why on Linux some program could not run
>> correctly.
>> for example
>> #include <stdio.h>
>> main()
>> {
>> printf("test\n");
>> fflush(stdout);
>> }
>> They will not echo what I print.
>
> Oh yes it will. I bet you named the executable "test" ... :-)
> (this is a UNIX faq).
>
</pre>
<blockquote> <B>
I really suggest that people learn the tao of "./"
<p>
This is easy -- any time you mean to refer to any file
in the current directory precede it with "./" -- this
forces all common Unix shells to refer to the file in
THIS directory. It solves all the problems with files
that start with dashes and it allows you to remove :.:
from your path (which *all* sysadmins should do right
NOW).
<p>
That is the tao of "./" -- the two keystrokes that can
save you many hours of grief and maybe save your whole
filesystem too.
</B> </blockquote>
<p><hr><p>
<!--================================================================-->
<a name="server"><p></a>
<h3><img align=bottom alt=" " src="../gx/ques.gif">
WWW Server?
</h3>
Date: Tue, 31 Dec 1996 05:19:11 -0800 (PST) <BR>
From: (Paulo Marcio Villaca Veiga) <A
HREF="mailto:paulom@cedro.fisica.ufmg.br">paulom@cedro.fisica.ufmg.bri</a><BR>
<P>
Where can I get (or buy) a WWW server for LINUX? <BR>
Please, help me.
<blockquote> <B>
Web servers are included with most distributions
of Linux. The most popular one right now is
called Apache. You can look on your CD's
(if you bought a set) or you can point a
web client (browser) at http://www.apache.org
for more information and for an opportunity to
download a copy.
<P>
There are several others available -- however
Apache is the most well known -- so it will be
the best for you to start with. It is also
widely considered to offer the best performance
and feature set (of course that is a matter
of considerable controversy among "connosieurs"
just as is the ongoing debate about 'vi' vs. 'emacs').
</B> </blockquote>
thank you
<blockquote> <B>
You're welcome.
</B> </blockquote>
<P> <hr> <P>
<center><H5>Copyright &copy; 1997, James T. Dennis <BR>
Published in Issue 13 of the Linux Gazette</H5></center>
<P> <hr> <P>
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<H4>
&quot;Linux Gazette...<I>making Linux just a little more fun!</I>
&quot;</H4>
<P> <HR> <P>
<!--===================================================================-->
<center>
<H1>COMDEX '96</H1>
<H4>By Belinda Frazier and Kevin Pierce</H4>
</center>
<P> <HR> <P>
<!--===================================================================-->
Comdex/Fall '96 has come and gone once again.
COMDEX is the second largest computer trade show in the world,
offering multiple convention floors with 2000 exhibitors plying their
new computer products to approximately 220,000 attendees in Las Vegas,
Nevada in November of 1996.
<p>
This year's show was a great success for Linux in general.
The first ever ``Linux Pavilion'' was organized at the Sands Convention
Center and Linux vendors from all over the country participated.
The Linux International (LI) booth was in the center, giving away
literature and information for all the Linux Vendors.
Linux International is a not-for-profit organization formed to promote
Linux to computer users and organizations.
Staffed by volunteers including Jon ``Maddog'' Hall
and Steve Harrington, the LI
booth was a great place for people to go to have their questions
answered. Needless to say, the Linux International Booth was never
empty. Surrounding LI, were Red Hat Software and WorkGroup Solutions.
<p>
Other vendors in the pavilion included Craftwork Solutions, DCG Computers,
Digital Equipment Corporation, Frank
Kasper & Associates, Infomagic, Linux Hardware
Solutions, SSC (publishers of Linux Journal), and Yggdrasil Computing.
Caldera, Pacific HiTech, and Walnut Creek both exhibited at
Comdex, but not as part of the Linux Pavilion.
<p>
SSC gave out Linux Journals at the show and actually ran out of magazines
early Thursday morning. Luckily, we were able to have some more shipped to us,
but we still ran out again on Friday, the last day of the show.
Comdex ran five full days and the Sands pavilion was open from 8:30 to
6 most show days which meant long days for all the exhibitors there.
<p>
Show management put up signs, directing attendees to the Linux
Pavilion and to "more Linux vendors".
The show was so large that it was easy to get lost.
<p>
At the LI booth and at SSC's booth, the response to Linux was
overwhelmingly positive.
Questions ranged from ``I've heard a lot about Linux, but I'm
not sure what it is, can
you enlighten me?'' to ``I haven't checked for a few days---what is the
latest development kernel?''
<p>
For next year's Comdex in November '97, Linux vendors, coordinated by
Linux International, are already working to put together a Linux
pavilion at least three times as big as the one this year.
<P>
Vendors interested in being part of the Linux pavilion in November '97
may contact
Softbank who put on Comdex at mandino@comdex.com or to do this through Linux International,
contact ``Jon Maddog'' Hall via e-mail at <A
HREF="mailto:maddog@zk3.dec.com">maddog@zk3.dec.com</A>.
<P> <hr> <P>
<center><H5>Copyright &copy; 1997, Belinda Frazier & Kevin Pierce <BR>
Published in Issue 13 of the Linux Gazette</H5></center>
<!--===================================================================-->
<P> <hr> <P>
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<H4>
&quot;Linux Gazette...<I>making Linux just a little more fun!</I>
&quot;</H4>
<P> <HR> <P>
<!--===================================================================-->
<center>
<h1>Filtering Advertisements from Web Pages using IPFWADM</h1>
<H4>By David Rudder
<a href="mailto:drig@magicweb.com">drig@magicweb.com</a></H4>
</center>
<P> <HR> <P>
Lately, a lot of Web pages have begun selling ad space &quot;banners.&quot;
Wasting valuable bandwidth, these banners often hawk products I don't
care to hear about. I'd rather not see them, and not have to download
their contents.
<p>
There are two ways of filtering out these banners. The first is to
deny all pictures that are wider than tall and generally towards the
top or bottom of the page. The second is to simply block all the
accesses to and from the web sites that are the notorious advertisers.
This second approach is the one I'm going to take.
<p>
When searching around the web, you will see that many of the banners
come from the site ad.linkexchange.com. This is the site we will want
to ban.
<P> <HR> <P>
<center><h3>Setting Up Your Firewall</h3></center>
<p>
Our first order of business is to set up our firewall. We won't be
using it for security, although this doesn't prohibit also using the
firewall for security. First, we recompile the kernel, saying
&quot;Yes&quot;
to CONFIG_FIREWALL. This allows us to use the built in kernel
firewalling.
<p>
Then, we need to get the IPFWADM utility. You can find it at:
<a
href="http://www.xos.nl/linux/ipfwadm">http://www.xos.nl/linux/ipfwadm
</a>. Untar, compile and install this utility.
<p>
Since we are doing no other firewalling, this should be sufficient.
</p>
<P> <HR> <P>
<center><h3>Blocking Unwanted Sites</h3></center>
<p>
Now, we come to the meat of the maneuver. We need now to block access
to our machine from ad.linkexchange.com. First, block out access to
the sight, so that our requests don't even make it there.
<tt>ipfwadm -O -a reject -P tcp -S 0.0.0.0/0 -D ad.linkexchange.com 80</tt><br>
<p>
This tells ipfwadm to append a rule to the Output filter. The rule
says to reject all packets of protocol TCP from anywhere to
ad.linkexchange.com on port 80. If you don't get this, read Chris
Kostick's excellent article on IP firewalling at
<a href="http://www.ssc.com/lj/issue24/1212.html">
http://www.ssc.com/lj/issue24/1212.html</a>.
<p>
The next rule is to keep any stuff from ad.linkexchange.com from
coming in. Technically, this shouldn't be necessary. If we haven't
requested it, it shouldn't come. But, better safe than sorry.
<tt>ipfwadm -I -a reject -P tcp -S ad.linkexchange.com 80 -D 0.0.0.0/0</tt><br>
<p>
Now, all access to and from ad.linkexchange.com is rejected.
<p>
<em>Note:</em> this will only work when web browsing from that machine. To
filter for a whole network, do them same but with -F instead of -O and
-I.
<P> <HR> <P>
<center><h3>Testing It Out</h3></center>
<p>
To test, visit the site <a href="http://www.reply.net">http://www.reply.net</a>. They have a banner on
top which should either not appear or appear as a broken icon. Either
way, no network bandwidth will be wasted downloading the picture, and
all requests will be rejected immediately.
</p>
<P> <HR> <P>
<center><h3>Filling It Out</h3></center>
<p>
Not all banners are so easily dealt with. Many companies, like Netscape, host their
own banners. You don't want to block access to Netscape, so this
approach won't work. But, you will find a number of different
advertisers set up like linkexchange. As you find more, add them to
the list of rejected sites.
</p>
Good luck, and happy filtering!
<P> <hr> <P>
<center><H5>Copyright &copy; 1997, David Rudder <BR>
Published in Issue 13 of the Linux Gazette</H5></center>
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&quot;Linux Gazette...<I>making Linux just a little more fun!</I>
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<P><HR NOSHADE><P>
<H1 ALIGN=CENTER>Floppy Disk Tips</H1>
<H4 ALIGN=CENTER>
By <A HREF="http://www.beachnet.org/bduncan/">
Bill Duncan</A>, <FONT SIZE=-1><I>VE3IED</I></FONT>,
<A HREF="mailto:bduncan@beachnet.org"><TT>bduncan@beachnet.org</TT></A></H4>
<P><HR NOSHADE><P>
<P>Although more computers are becoming network connected every day,
there are many instances where you need to transfer files by the ol'
<I>sneaker-net</I> method. Here are some hints, tips and short-cuts for doing
this, aimed at users who are new to Linux or Unix. (There may even be
some information useful to old-timers...)
<UL>
<LI><A HREF="#FORMAT">Formatting, Filesystems and Mounting</A>
<LI><A HREF="#BACKUP">Backups, Cpio and Gzip</A>
<LI><A HREF="#LARGE">Floppy as a Raw Device for Large Files or Directories</A>
<LI><A HREF="#MISC">Miscellaneous</A>
</UL>
<P>What do I use floppies for? As a consultant, I frequently do contract
work for companies which, because of security policies, do not connect
to the 'Net. So, FTP'ing files which I need from my network at home is out of
the question.
<P>My current contract as an example, I am using Linux as an X-Windows terminal
for developing software on their DEC Alphas running OSF. (I blew away the
Windoze '95 which they had loaded on the computer they gave me.) I often need to bring
files with me from my office at home, or backup my work to take back home
for work in the evening. (Consultants sometimes work <I>flex-hours</I>, which generally
means more hours...)<P>
<P>Why use <B>cpio</B>(1) or <B>tar</B>(1) when copying files? Because it is a
<I>portable</I> method of transferring files from a group of subdirectories
with the file dates left intact. The <B>cp</B>(1) command may or may not do the
job depending on Operating Systems and versions you are dealing with.
In addition, specifying certain options will only copy files which are new or
have changed.
<P>
<A NAME="FORMAT">
<P><HR NOSHADE><P>
<H2>Formatting, Filesystems and Mounting</H2></A>
<P><HR NOSHADE><P>
The first thing you need to do to make the floppies useful is to format them,
and usually lay down a filesystem. There are also some preliminary steps
which make using floppy disks much easier, which is the point of this article.
<P>I find it useful to make my username part of the <B>floppy</B> group in the
<B>/etc/group</B> file. This saves you from needing to su to root much of
the time. (You will need to log out and log back in again for this to take
effect.)
I also use the same username both on the client's machine and
my home office which saves time. The line should now look like this:<BR>
<BLOCKQUOTE>
<PRE>
floppy::11:root,<EM>username</EM>
</PRE>
</BLOCKQUOTE>
<P>The following setup is assumed for the examples I present here.
The root user must have the system directories in the <STRONG>PATH</STRONG>
environment variable.
Add the following to the <B>.profile</B> file in /root if not already there by
su'ing to root.<BR>
<BLOCKQUOTE>
<PRE>
su - # this should ask for the <EM>root</EM> password.
cat >> <B>.</B>profile
PATH=/sbin<B>:</B>/usr/sbin<B>:</B>$PATH
&lt;ctrl&gt;-D
</PRE></BLOCKQUOTE>
<!-- TIP TAG -->
You can also use your favorite editor to do this... I prefer <B>vim</B>(1) and
have this <I>symlink</I>ed to <B>/usr/bin/vi</B> instead of <B>elvis</B>(1) which is
usually the default on many distributions. VIM has online help, and multiple
window support which is very useful! (A <I>symlink</I> is created with a
<B>-s</B> option to <B>ln</B>(1), and is actually called a
<I>sym</I>bolic&nbsp;<I>link</I>.)
<P>Next, add the following lines to the <B>/etc/fstab</B> file:
(I have all the user mountable partitions in one place under <B>/mnt</B>.
You may want a different convention, but this is useful. I also have
/mnt/cdrom symlinked to /cd for convenience.)<BR>
<BLOCKQUOTE>
<PRE>
/dev/fd0 /mnt/fd0 ext2 noauto,user 1 2
</PRE>
</BLOCKQUOTE>
<P>Still logged in as root, make the following symlink:
(If you have more than one floppy drive, then add the floppy number
as well.)<BR>
<BLOCKQUOTE>
<PRE>
ln -s /mnt/fd0 /fd
-or-
ln -s /mnt/fd0 /fd0
</PRE>
</BLOCKQUOTE>
These two things make mounting and unmounting floppies a cinch. The
<B>mount</B>(8) command follows the symlink and
accesses the <B>/etc/fstab</B> file for any
missing parameters, making it a useful shortcut.
<P>To make the floppy usable as an ext2fs Linux filesystem, do the following
as root:
(The <I>username</I> is whatever username you use on regularly on the
system. You, of course, should not use the <I>root</I> user for normal
use!)
<BR>
<BLOCKQUOTE>
<PRE>
export PATH=/sbin:/usr/sbin:$PATH # not needed if you set environment
fdformat /dev/fd0
mke2fs /dev/fd0
mount /dev/fd0 /mnt/fd0
chown username /mnt/fd0
</PRE>
</BLOCKQUOTE>
You may need to specify the geometry of the floppy you are using.
If it is the standard 3.5 inch double sided disk, you may need to
substitute <B>/dev/fd0H1440</B> for the device name (in 1.2.x kernels).
If you have a newer 2.xx kernel and <B>superformat</B>(1), you may want
to substitute this for <B>fdformat</B>. See the notes in the
<A HREF="#MISC">Miscellaneous</A> section below, or look at the man page.
You may now exit out of <B>su</B>(1) by typing:
<BLOCKQUOTE>
<PRE>
exit
</PRE>
</BLOCKQUOTE>
<P>From this point on, you may use the <B>mount</B>(8) and <B>umount</B>(8)
commands logged in as your normal username by typing the following:<BR>
<BLOCKQUOTE>
<PRE>
mount /fd
umount /fd
</PRE>
</BLOCKQUOTE>
<A NAME="BACKUP">
<P><HR NOSHADE><P>
<H2>Backups, Cpio and Gzip</H2></A>
<P><HR NOSHADE><P>
<P>For backing up my work to take home or to take back to the office I use
<B>cpio</B>(1) instead of <B>tar</B>(1) as it is far more flexible, and
better at handling errors etc. To use this on a regular basis, first create
all the files you need by specifying the command below <EM>without</EM>
the <B>-mtime -1</B> switch. Then you can make daily backups from the base
directory of your work using the following commands:<BR>
<BLOCKQUOTE>
<PRE>
cd <EM>directory</EM>
mount /fd
find <B>.</B> -mtime -1 -print | cpio -pmdv /fd
sync
umount /fd
</PRE>
</BLOCKQUOTE>
<P>
When the floppy stops spinning, and the light goes out, you have your
work backed up. The <B>-mtime</B> option to <B>find</B>(1) specifies
files which have been modified (or created) within one day (the <B>-1</B>
parameter). The options for <B>cpio</B>(1) specify <EM>copy-pass</EM> mode,
which retain previous file modification times, create directories where needed,
and do so verbosely. Without a <B>-u</B> (<I>unconditional</I>) flag, it will
not overwrite files which are the same age or newer.
<P>
This operation may also be done over a network, either from NFS mounted filesystems,
or by using a remote shell as the next example shows.
<BLOCKQUOTE>
<PRE>
mount /fd
cd /fd
rsh remotesystem '(cd <I>directory</I>; find <B>.</B> -mtime -1 -print | cpio -oc)' |
cpio -imdcv
sync
cd
umount /fd
</PRE>
</BLOCKQUOTE>
This example uses <B>cpio</B>(1) to send files from the remote system, and
update the files on the floppy disk mounted on the local system. Note the
<I>pipe</I> (or veritical bar) symbol at the end of the remote shell line.
The arguments which are enclosed in quotes are executed remotely, with
everything enclosed in braces happening in a subshell. The <I>archive</I>
is sent as a stream across the network, and used as input to the <B>cpio</B>(1)
command executing on the local machine. (If both systems are using a recent
version of GNU cpio, then specify <B>-Hcrc</B> instead of <B>c</B> for the
archive type. This will do error checking, and won't truncate inode numbers.)<BR>
The remote system would have: <I>cpio -oHcrc</I><BR>
and the local side would have: <I>cpio -imdvHcrc</I><P>
<P>To restore the newer files to the other computer, change directories to
the <I>base directory of your work</I>, and type the following:<BR>
<BLOCKQUOTE>
<PRE>
cd <EM>directory</EM>
mount -r /fd
cd /fd
find <B>.</B> -mtime -1 -print | cpio -pmdv ~-
cd -
umount /fd
</PRE>
</BLOCKQUOTE>
<P>
If you needed to restore the files completely, you would of course leave out
the <B>-mtime</B> parameter to <B>find</B>(1).
<P>
<!-- TIP TAG -->
<P>The previous examples assume that you are using the <B>bash</B>(1) shell,
and uses a few quick tricks for specifying directories. The &quot;<B>~-</B>&quot;
parameter to cpio is translated to the <I>previous default directory</I>.
In other words, where you were before cd'ing to the /fd directory.
(Try typing: <TT>echo ~-</TT> to see the effect, after you have changed
directories at least once.)
The <B>cd ~-</B> or just <B>cd -</B> command is another shortcut to switch
directories to the previous default. These shortcuts often save a lot of time
and typing, as you frequently need to work with two directories, using this
command to alternate between them or reference files from where you were.
<P>If the directory which you are tranferring or backing up is larger than
a single floppy disk, you may need to resort to using a compressed archive.
I still prefer using <B>cpio</B>(1) for this, although <B>tar</B>(1) will
work too. Change directories to your work directory, and issue the following
commands:
<BLOCKQUOTE>
<PRE>
cd <EM>directory</EM>
mount /fd
find <B>.</B> -mtime -1 -print | cpio -ovHcrc | gzip -v > /fd/backup.cpio.gz
sync
umount /fd
</PRE>
</BLOCKQUOTE>
The <B>-Hcrc</B> option to cpio(1) is a new type of archive which older
versions of cpio might not understand. This allows error checking, and
inode numbers with more than 16 bits.
<P>Of course, your original archive should be created using <B>find</B>(1)
without the <I>-mtime -1</I> options.
<A NAME="LARGE">
<P><HR NOSHADE><P>
<H2>Floppy as a Raw Device for Large Files or Directories</H2></A>
<P><HR NOSHADE><P>
Sometimes it is necessary to backup or transfer a file or directories which
are larger than a floppy disk, even when compressed. For this, we finally
need to resort to using tar.
<P>Prepare as many floppies as you think you'll need by using the <B>fdformat</B>(8)
command. You do not need to make filesystems on them however, as you will be
using them in <I>raw</I> mode.
<P>If you are backing up a large set of subdirectories, switch to the base
subdirectory and issue the following command:
<BLOCKQUOTE>
<PRE>
cd <EM>directory</EM>
tar -cv -L 1440 -M -f /dev/fd0 <B>.</B>
</PRE>
</BLOCKQUOTE>
This command will prompt you when to change floppies. <STRONG><EM>Wait for the
floppy drive light to go out of course!</EM></STRONG>
<P>If you need to backup or transfer multiple files or directories, or just a single
large file, then specify them instead of the period at the end of the tar command
above.
<!-- I made the period bold, as it didn't show up very well otherwise -->
<P>Unpacking the archive is similar to the above command:<BR>
<BLOCKQUOTE>
<PRE>
cd <EM>directory</EM>
tar -xv -L 1440 -M -f /dev/fd0
</PRE>
</BLOCKQUOTE>
<A NAME="MISC">
<P><HR NOSHADE><P>
<H2>Miscellaneous</H2></A>
<P><HR NOSHADE><P>
Finally, here are some assorted tips for using floppies.
<P>The <B>mtools</B>(1) package is great for dealing with MS-DOG
floppies, as we sometimes must. You can also <B>mount</B>(8) them as a Linux
filesystem with either msdos or umsdos filesystem types. Add another
entry to the <B>/etc/fstab</B> entry you made before, so that the two
lines will look like this:<BR>
<BLOCKQUOTE>
<PRE>
/dev/fd0 /mnt/fd0 ext2 noauto,user 1 2
/dev/fd0 /mnt/dos msdos noauto,user 1 2
</PRE>
</BLOCKQUOTE>
You can now mount an MS-DOS floppy using the command:<BR>
<BLOCKQUOTE>
<PRE>
mount /mnt/dos
</PRE>
</BLOCKQUOTE>
You can also symlink this to another name as a further shortcut.
<BLOCKQUOTE>
<PRE>
ln -s /mnt/dos /dos
mount /dos
</PRE>
</BLOCKQUOTE>
<!-- TIP TAG -->
<P>The danger of using the <B>mount</B>(8) commands rather than <B>mtools</B>(1)
for users who are more familiar with MSDOS, is that <B><I>you need to explicitly
unmount floppies</I></B> before taking them out of the drive using
<B>umount</B>(8).
Forgetting this
step can make the floppy unusable! If you are in the habit of forgetting, a simple
low-tech yellow Post-it note in a strategic place beside your floppy drive might
save you a few headaches. If your version of Post-it notes has the &lt;BLINK&gt;
tag, use it!&nbsp;&nbsp;&nbsp;<TT>;-)</TT><BR>
<BLOCKQUOTE>
<TABLE BORDER=0 CELLPADDING=9><TR><TD BGCOLOR="#ffffcc">&quot;<B><I><BLINK>umount
me first!</BLINK></I></B>&quot;</TD></TR></TABLE>
</BLOCKQUOTE>
<!-- sorry for that blink tag... ;-) -->
<P>Newer systems based on the 2.xx kernel are probably shipped with <B>fdutils</B>.
Check to see if you have a <B>/usr/doc/fdutils-xxx</B> directory,
where xxx is a version number. (Mine is 4.3).
Also check for the <B>superformat</B>(1) man page. This supersedes
<B>fdformat</B>(1) and gives you options for packing much more
data on floppies. If you have an older system, check the
<A HREF="ftp://ftp.imag.fr/pub/Linux/ZLIBC/fdutils/">ftp://ftp.imag.fr/pub/Linux/ZLIBC/fdutils/</A>
ftp site for more information.
<P>The naming convention for floppies in newer 2.xx kernels has also changed,
although the <B>fd</B>(4) man page has not been updated in my distribution.
If you do not have a <B>/dev/fd0H1440</B> device, then you probably have the newer
system.
<P> <hr> <P>
<center><H5>Copyright &copy; 1997, Bill Duncan <BR>
Published in Issue 13 of the Linux Gazette</H5></center>
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<LI><I>v;</I> to become absorbed in thought
<LI><I>n;</I> [ fr. Any of the nine sister goddesses of learning and the
arts in Greek Mythology ]: a source of inspiration
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computer graphics tools for Linux systems.
<BR clear=both>
&nbsp; &nbsp; &nbsp;
Last month I introduced a new format to this column. The response was
mixed, but generally positive. I'm still getting more comments on the
format of the column rather than the content. I don't know if this
means I'm covering all the issues people want to hear about or people
just aren't reading the column. Gads. I hope its not the latter.
<BR clear=both>
&nbsp; &nbsp; &nbsp;
This months issue will include another book review, a discussion on
adding fonts to your system, a Gimp user's story, and a review of the
AC3D modeller. The holiday season is always busy one for me. I would
have liked to do a little more, but there just never seems to be enough
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&nbsp; &nbsp; &nbsp;
Disclaimer:
Before I get too far into this I should note that any of the news items I
post in this section are just that - news. Either I happened to run across
them via some mailing list I was on, via some Usenet newsgroup, or via
email from someone. I'm not necessarily endorsing these products (some of
which may be commercial), I'm just letting you know I'd heard about them in
the past month.
<BR clear=both>
&nbsp; &nbsp; &nbsp;
I went wondering through a local computer book store this month
and scanned the graphics texts section. I found a few new tidbits
that might be of interest to some of you.
&nbsp; &nbsp; &nbsp;
<tr>
<td width="50%">
<H4>3D Graphic File Formats: A Programmers Reference
</H4>
&nbsp; &nbsp; &nbsp;
<A HREF="http://www.europa.com/~keithr/">
Keith Rule</A> has written a new book on 3D Graphics File Formats.
The book, which contains over 500 pages,
has been published by Addison-Wesley Developers Press
and is listed at $39.95. It includes a CD-ROM
with a software library for processing various 3D file formats
(both reading and writing), but the code is written for
MS systems. Keith states there isn't any reason why the code
shouldn't be portable to other platforms such as Linux. Any
takers out there? <BR>ISBN 0-201-48835-3
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<H4>OpenGL Programming for the X Window System </H4>
&nbsp; &nbsp; &nbsp;
I noticed a new text on the shelf of a local book store
(Softpro, in Englewood, Colorado) this past month - Mark J. Kilgard's
<I>OpenGL Programming for the X Window System</I>. This book,
from Addison Wesley Developers Press, appears to have a very good
coverage of how to write OpenGL applications that make use of X Windows
API's. I haven't read it yet (or even purchased it - yet, but I
will) so can't say how good it is. Mark is the author of the GLUT
toolkit for OpenGL. GLUT is to OpenGL what Xt or Motif is to Xlib.
Well, sort of.
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<H4>Fast Algorithms for 3D-Graphics</H4>
&nbsp; &nbsp; &nbsp;
This book, by Georg Glaeser and published by Springer, includes
a 3.5" diskette of source for Unix systems. The diskette,
however, is DOS formatted. All the algorithms in the text are
written using pseudocode, so readers could convert the algorithms
to the language of choice.
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<H4>ImageMagick 3.7.8 released, including a new set of image
library plug-ins
</H4>
&nbsp; &nbsp; &nbsp;
A new release of ImageMagick has been released from
<A HREF="mailto:Alexander.Zimmermann@FMI.Uni-Passau.De">
Alexander Zimmermann</A>. This release includes a "Plug In"
library containing the various image libraries ImageMagick
needs to run. Alexander has uploaded this new release to
<A HREF="ftp://sunsite.unc.edu/pub/Linux/X11/xapps/graphics">
Sunsite</A>
as well as
<A HREF="ftp://ftp.wizards.dupont.com/pub/ImageMagick/binaries">
ImageMagick's Web site.
<tr>
<td colspan=4 bgcolor="#000000" cellpadding=0 cellspacing=0 valign=top>
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<tr>
<td width="50%">
<H4>MpegTV Player v0.9</H4>
&nbsp; &nbsp; &nbsp;
A new version of the
<A HREF="http://www.mpegtv.com">
MpegTV Player</A>
has been released. This version now includes audio support.
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<td width="49%">
<H4> Imaging Technology Inc. IC-PCI frame grabber board driver </H4>
&nbsp; &nbsp; &nbsp;
The
<A HREF="ftp://gandalf.expmech.ing.tu-bs.de/pub/driver/icpci-0.2.0.tar.gz">
second public release (v 0.2.0)</A>
of a kernel module for the
Imaging Technology Inc. IC-PCI frame grabber board (rev 1)
and the AM-VS acquisition module
has been released. This driver is maintained by
GOM mbH (Gesellschaft fuer optische Messtechnik)
TU Braunschweig, Institute for Experimental Mechanics.
A full motion video test program and a read function for
original camera files are included.
<BR>Author: <A HREF="mailto: matthias@expmech.ing.tu-bs.de">Matthias
Stein</A>
<BR>Maintained by: <A HREF="mailto: d.bergmann@tu-bs.de">Dirk Bergmann</A>
<BR>This software is not really free (see the LICENSE file).
<tr>
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<tr>
<td colspan=4>
<H4>Viewmol 2.0 released</H4>
&nbsp; &nbsp; &nbsp;
I don't know much about this tool, but it appears to have alot
of graphics related features, so I thought I'd mention it here.
The LSM gives the following information:
<P>
Viewmol is a program for the visualization of outputs from
quantum chemical as well as from molecular mechanics programs.
Currently supported are Gaussian 9x, Discover, DMol/DSolid,
Gulp, Turbomole, and PDB files. Properties visualized include
geometry (with various drawing modes), vibrations (animated
or with arrows), optimization history/MD trajectories, MO
energy level diagram, MOs, basis functions, electron density.
Drawings can be saves as TIFF, HPGL, Postscript, input files
for Rayshade.
<P>
<A HREF="ftp://ftp.ask.uni-karlsruhe.de/pub/education/chemistry/viewmol-2.0.tgz">
ftp://ftp.ask.uni-karlsruhe.de/pub/education/chemistry/viewmol-2.0.tgz</A>
</td>
<tr>
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<IMG SRC=../gx/hammel/cleardot.gif ALT="indent" ALIGN="left"
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HSPACE="0" WIDTH="0" HEIGHT="0"></td>
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VSPACE="5" HSPACE="10" WIDTH="1" HEIGHT="1"></td>
<tr>
<td colspan=4>
<H4>Did You Know?</H4>
&nbsp; &nbsp; &nbsp;
<A HREF="http://www.3dsite.com/3dsite">
3D Site (http://www.3dsite.com/3dsite)</A>
is a Web site devoted to everything 3D. There are
job postings, links to free repositories of 3D models and lots
of other valuable information.
<P>
&nbsp; &nbsp; &nbsp;
<A HREF="http://156.46.199.2/3dcafe/">
3D Cafe (http://156.46.199.2/3dcafe/)</A>
is another Web site with various useful 3D information.
It also maintains a large collection of DXF and 3DS model
files.
<P>
<H4>An Important Survey</H4>
&nbsp; &nbsp; &nbsp;
I've been talking to a couple of publishers about doing a book aimed at
Linux users. I'd like to write a User's Guide for the Gimp but the
publisher feels a more general text on doing Web-based graphics might have
a wider appeal (face it - the Linux audience just isn't the size of the MS
audience - yet - but the publishers are considering both types of books).
I told them I'd ask my readers which type of text
they'd like to see. The Gimp book would include details on how to
use each of the applications features as well as a number of tutorials for
doing various types of effects. The book on doing graphics for Web pages
would include discussions on using HTML, information on tools besides the
Gimp and a few case studies (including something on animation). However,
the Web book wouldn't go into as much detail for each of the tools.
That information would be more general in nature.
<BR clear="both">
&nbsp; &nbsp; &nbsp;
I don't have a server to run any CGI scripts to register votes, so
simply <A HREF="mailto:mjhammel@csn.net">mail me</A> with your
opinions. Thanks!
<P>
<H4>A Call for Help</H4>
&nbsp; &nbsp; &nbsp;
I plan on covering more 3D tools in the future, but I have to learn
to use them first. The next tool I'm going to look into is BMRT.
If you use BMRT and want to help me get started
<A HREF="mailto:mjhammel@csn.net">drop me a line</A>. I'd like to
do an introduction to BMRT in the March issue if possible but I want to make
sure I know what I'm talking about first. Thanks!
<tr>
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<IMG SRC=../gx/hammel/cleardot.gif ALT="indent" ALIGN="left"
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<IMG SRC=../gx/hammel/cleardot.gif ALT="indent" ALIGN="left"
HSPACE="0" WIDTH="0" HEIGHT="0"></td>
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<IMG SRC=../gx/hammel/cleardot.gif ALT="indent" ALIGN="left"
VSPACE="5" HSPACE="10" WIDTH="1" HEIGHT="1"></td>
</table>
<P>
<A NAME="musings">
<table>
<tr>
<td>
<IMG SRC=../gx/hammel/musings.gif ALT="Musings" ALIGN="left"
HSPACE="0" VSPACE="0" WIDTH="247" HEIGHT="52">
</td>
</table>
</A>
<BR clear=both>
<TABLE width=560>
<tr>
<td valign=top>
&nbsp; &nbsp; &nbsp;
<H4>A Gimp User's Story (or "Why I Use the Gimp")</H4>
The following piece was posted on the Gimp User's Mailing
list by <A HREF="mailto: mike@lawlib.wm.edu"> Mike Phillips</A>.
<P>
&nbsp; &nbsp; &nbsp;
At work, we have a "Library News Network", which is actually a 386 pc
running a TV via a video converter in a continual slideshow with
information about upcoming events in the law library and the law school.
Last year, my boss did some stuff in Freelance Graphics which, quite
frankly, was rather limited in effect.
<BR clear=both>
&nbsp; &nbsp; &nbsp;
This year, it's my baby, and I'm making the slideshow (640x480x256 GIF
files, run by a simple DOS program and looped by a batch file) in the
GIMP. Here are some things I've done to make the text more readable
and make the display reasonably eye-catching. Nothing fancy, but
hopefully the tricks will give other people ideas to play with on their
own.
<BR clear=both>
&nbsp; &nbsp; &nbsp;
First, don't use a plain background. The blend tool is very nice for
this, and shaded green or blue with bright text is rather nice looking.
Start with a color and add some noise Create a blend image of the
same size and multiply by the image with noise. This creates a
<I>very</I> cool background for a slide. Better yet, if there's an
appropriate photograph, use it! (I used a gorgeous picture of Yosemite
Park to announce an environmental law symposium, and a decent photo of
the U.S. Supreme Court justices to announce our Supreme Court Preview.)
<BR clear=both>
&nbsp; &nbsp; &nbsp;
On the subjects of backgrounds, since I don't remember seeing this tip,
here's a quickie for clouds: Make a plasma of the appropriate size,
grayscale it, convert it back to color, and Brightness/Contrast/Gamma it
into submission. I usually knock the brightness up about 75-100, and the
blue up to around 5 and the green to about 2. Instant pretty sky
(Obviously, skies from other planets could be done with reds and greens
and whatnot.)
<BR clear=both>
&nbsp; &nbsp; &nbsp;
For the text, nothing beats some good fonts. Hit a
<A HREF="ftp://ftp.cdrom.com/pub/os2/fonts/">font archive</A>,
or buy
a $10-$15 CD filled with fonts. Granted, I have the Caldera Network
Desktop, so I can use some fonts that (I think) XFree can't, thanks to
the font server, but it's worth a shot. I got a CD with 1250 fonts for
$13.
[Ed. Next month I'll cover how to add fonts to your system so you
can use them with the Gimp. mjh]
<BR clear=both>
&nbsp; &nbsp; &nbsp;
Here's a variation on the
<A HREF="http://abattoir.cc.ndsu.nodak.edu/~nem/gimp/">rounded-text tips</A>:
work out your
text, then Duplicate it once and Offset it once (say 4x4). Edge Detect
then Invert the duplicate and Gaussian Blur the offset twice. Multiply
the resulting images, and use the original as a mask to composite
something else over the image resulting from the multiplication.
Very nice, edged & floating/shadowed
text. Shows up great on a TV monitor.
<BR clear=both>
&nbsp; &nbsp; &nbsp;
For the text, use any appropriate single color. Bright colors and high
contrast work very well for what I do, although I've played with
textures, rippled blends, plasma clouds, and what-not.
<BR clear=both>
&nbsp; &nbsp; &nbsp;
Of course, it can be spiced up with all sorts of clipart (I heartily
recommend
<A HREF="http://www.barrysclipart.com">
Barry's Clipart Server (www.barrysclipart.com)</A>,
from which I shamelessly borrow, and voila, instant slideshow!
<BR clear=both>
&nbsp; &nbsp; &nbsp;
I have left our Fall Break edition of the LNN at:
<A HREF="http://www.lawlib.wm.edu/LNN-old/">
http://www.lawlib.wm.edu/LNN-old/</A>.
if you want to see some of what can be done with it. You might be better
off watching the show when the graphics aren't resized to 320x240.
Also, the latest version of these is available at
<A HREF="http://www.lawlib.wm.edu/LNN/">
http://www.lawlib.wm.edu/LNN/</A>.
<P>
<BR clear=both>
[Ed. Later Mike posted another message that included some
interesting effects. I thought it might be appropriate to include them
with his other posting.]
<P>
<BR clear=both>
&nbsp; &nbsp; &nbsp;
Recently, while wandering through the plug-ins available, I found the
charcoal plug-in. Compiled it, added it, used it. Rather nifty, actually.
However, it got me thinking and experimenting, and I produced two
potentially interesting effects:
<P>
(1) Pastel sketch: Take a color (RGB) image, Edge-detect it, Invert, and
(optionally) contrast autostretch. On many images, this will produce a
nifty pastel sketch. If the image is too high of detail, degrade the
color or pixelize it first, otherwise you may end up with too many
extraneous lines.
<P>
(2) Watercolor sketch: Take a color (RGB) image, make a grayscale of it.
Edge Detect the grayscale (this will give you the sketch lines); this can
be hard to balance the way you want, so you may want to threshold it or
pixelize the image first. Then, pixelize and degrade the main image to
32 colors (16 or 20 works even better). Eliminate the background you
don't want, Gaussian blur it a few times, and brighten it some.
Multiply the edging onto it. Voila; (nearly) instant watercolor,
akin to the court sketches on news shows.
<P>
<A HREF="mailto: mike@lawlib.wm.edu">Mike Phillips, mike@lawlib.wm.edu</A>
</td>
<tr>
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<IMG SRC=../gx/hammel/cleardot.gif ALT="indent" ALIGN="left"
WIDTH="1" HEIGHT="1"></td>
</table>
<TABLE width=560>
<tr>
<td valign=top width="44%">
<H4><I>Jim Blinn's Corner - A Trip Down the Graphics Pipeline</I></H4>
<IMG SRC=../gx/hammel/cleardot.gif ALT="indent" ALIGN="left"
HSPACE="8" WIDTH="1" HEIGHT="1">
<IMG SRC=../gx/hammel/i.gif ALT="I" ALIGN="left"
HSPACE="0" VSPACE="0" WIDTH="13" HEIGHT="34">
am not formally trained in computer graphics
(<A HREF="#fn1">1</A>).
Everything I know
I've learned in the last year or so by reading, examining source
code, and through the kind assistance of many members of the Net.
So my ability to understand some of the more formal texts on
computer graphics is limited.
<BR>
&nbsp; &nbsp; &nbsp;
Given this limitation, I found I was still able to read and
comprehend a good portion of Jim Blinn's book
<I>Jim Blinn's Corner - A Trip Down the Graphics Pipeline</I>, which
is a collection of articles taken from his column in the <I>IEEE Computer
Graphics and Applications</I> journal. This book is the first of what may
be two books, assuming there is sufficient interest in the first book. The
second will cover a set of pixel arithmetic articles taken from the same
column.
<BR>
&nbsp; &nbsp; &nbsp;
In the preface Jim describes how he used a writing style that is
"certainly lighter than a typical SIGGRAPH paper, both in depth and in
attitude." I can't agree more. Computer graphics should be a fun
subject and, despite the math, this book does provide a giggle here
and there.
<BR>
&nbsp; &nbsp; &nbsp;
Don't get me wrong, though. There is plenty of the technical details
on how to compute positions in 3D space, perspective shadows, and
subpixelic particles. Hefty stuff for the beginner. Nearly
incomprehensible to the person who hasn't used matrix arithmetic in the
past 8 years. Still, chapters like <B>The Ultimate Design Tool</B>
(which talks about how an idea should start), and <B>Farewell to
Fortran</B> (which talks about using various languages in computer
graphics) provided enough non-mathematical discussions to let my brain
recover while still keeping my interest peaked.
<BR>
&nbsp; &nbsp; &nbsp;
I haven't read the book front to back yet. I'm saving whats left
(about half the book) for my 16 days of freedom scheduled to start later
this month. Its first on my reading list. Second will be my college
Linear Algebra text. The first half of Jim's book reminded me about how
much I'd forgotten in 8 years. Like the saying goes, one must strive
for the impossible before they know what is possible.
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<table>
<tr>
<td valign=top cellpadding=0 cellspacing=0>
<UL>
<LH>
<B>More Musings...</B>
</LH>
<LI>
<A HREF="more-musings.html#ac3d">
Review: The AC3D Modeller
</A> - An introduction to the very nifty 3D modeller
from Andy Colebourne.
Warning: lots of images on this page!
<LI>
<A HREF="png.html">
History of the Portable Network Graphics (PNG) format
</A> - A detailed look at how
an Internet-based cooperative effort
brought about this graphics file format specification.
</UL>
<IMG SRC=../gx/hammel/cleardot.gif ALT="indent" ALIGN="left"
VSPACE="5" WIDTH="1" HEIGHT="1">
</td>
<tr>
<td bgcolor="#000000" cellpadding=1 cellspacing=0 valign=top>
<IMG SRC=../gx/hammel/cleardot.gif ALT="indent" ALIGN="left"
WIDTH="1" HEIGHT="1"></td>
<tr>
<td valign=top cellpadding=0 cellspacing=0>
<IMG SRC=../gx/hammel/cleardot.gif ALT="indent" ALIGN="left"
HSPACE="8" WIDTH="1" HEIGHT="1">
<BR>
<IMG SRC=../gx/hammel/cleardot.gif ALT="indent" ALIGN="left"
HSPACE="8" WIDTH="1" HEIGHT="1">
<H4>The IRTC - A raytracing competition for the fun of it</H4>
<IMG SRC=../gx/hammel/cleardot.gif ALT="indent" ALIGN="left"
HSPACE="8" WIDTH="1" HEIGHT="1">
<IMG SRC=./gx/hammel/f.gif ALT="F" ALIGN="left"
HSPACE="0" VSPACE="0" WIDTH="23" HEIGHT="29">or
the past few months, I've been
helping to administer an Internet-based competition for users of
raytracing software. This competition, the Internet Ray
Tracing Competition or
<A HREF="http://www.povray.org/irtc/">IRTC</A>,
is open to anyone interested in creating 3D images using
software on any platform as long as the software falls
within a few
<A HREF="http://www.povray.org/irtc/mail/rules.html">basic guidelines</A>.
It is based on another competition started back in 1994 by Matt
Kruse. Matt eventually had to close down the contest due to
the enormous amount of time it takes to run such a contest. At the
time, he was more or less doing all the work himself.
<BR>
&nbsp; &nbsp; &nbsp;
Earlier this year Chip Richards started to organize the contest
once again. A group of interested individuals signed up to help
out. In the end, most of us (myself included) provide only
organizational input - ideas for rules or input on rulings regarding
cheating (yes, there has been some of that), helping to select topics, and
so forth. Most of the real work has been done by Chip, Bill Marrs,
and Jon Peterson (although Jon has since had to move on to other
things).
<BR>
&nbsp; &nbsp; &nbsp;
The contest is made up independent rounds that last 2 months. Each
round has a topic which entrants must use as the basis for their
images. Entries are supposed to be new images, created during the
span of the contest, however most people use bits and pieces of older
models that they or someone else has created. The tools allowed
vary but raytracing tools are preferred and no post processing is
allowed (for example, you can't add a lens flare after the image
has been rendered). Anyone is allowed to vote (currently) on the
images and winners receive small prizes like CDs and prints of their
images.
<P>
<CENTER>
<A HREF="more-musings.html#irtc">more IRTC...</A>
(same page as AC3D review)
</CENTER>
</td>
</table>
</td>
</table>
<P>
<A NAME="resources">
<table>
<tr>
<td>
<IMG SRC=../gx/hammel/resources.gif ALT="Resources" ALIGN="left"
HSPACE="0" VSPACE="0" WIDTH="246" HEIGHT="57">
</td>
</table>
</A>
<BR clear=both>
The following links are just starting points for finding more information
about computer graphics and multimedia in general for Linux systems. If
you have some application specific information for me, I'll add them to my
other pages or you can contact the maintainer of some other web site. I'll
consider adding other general references here, but application or site
specific information needs to go into one of the following general
references and not listed here.
<BR clear=both>
<P>
<A HREF="http://www.csn.net/~mjhammel/linux-graphics-howto.html">
Linux Graphics mini-Howto
</A>
<BR>
<A HREF="http://www.csn.net/~mjhammel/povray/povray.html">
Unix Graphics Utilities
</A>
<BR>
<A HREF="http://www.digiserve.com/ar/linux-snd/">
Linux Multimedia Page
</A>
<br>
<P>
<A NAME="future">
<H2>Future Directions</H2>
</A>
Next month:
<UL>
<LI>TkPOV - a POV-Ray scene file editor
<LI>Book Review: 3D Graphic File Formats by Keith Rule
<LI>Adding fonts to your system
<LI>Gimp Tips
<LI>...and lots more!
</UL>
<BR>
<A HREF="mailto:mjhammel@csn.net">
Let me know what you'd like to hear about!</A>
<P>
<HR>
<OL>
<LI><A NAME="fn1">
<FONT size=2>
Anyone having an extra, unclaimed scholarship in computer graphics
is encouraged to contact me. I give preference to those
who have them within commuting distance of Denver, where I live.
</FONT>
</A>
</OL>
<P> <hr> <P>
<center><H5>Copyright &copy; 1997, Michael J. Hammel <BR>
Published in Issue 13 of the Linux Gazette</H5></center>
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<A NAME="musings">
<table>
<tr>
<td>
<H2>More...</H2>
<BR clear=both>
<IMG SRC=../gx/hammel/musings.gif ALT="Musings" ALIGN="left"
HSPACE="0" VSPACE="0" WIDTH="247" HEIGHT="52">
</td>
</table>
</A>
<BR clear=both>
<table>
<tr><td>
<UL>
<LI><A HREF="#ac3d">Review: The AC3D Modeller</A>
<LI><A HREF="#irtc">more IRTC...</A>
</UL></td>
</table>
<IMG SRC=../gx/hammel/cleardot.gif ALT="indent" ALIGN="left"
VSPACE="5" WIDTH="1" HEIGHT="1">
<BR clear=both>
<table width=100%>
<tr>
<td width="100%" align=right>
<FONT size=1>
&copy 1996 <A HREF="mailto:mjhammel@csn.net">Michael J. Hammel</A>
</FONT></td>
<tr>
<td bgcolor="#000000" cellpadding=0 cellspacing=0 valign=top>
<IMG SRC=../gx/hammel/cleardot.gif ALT="indent" ALIGN="left"
HSPACE="0" WIDTH="0" HEIGHT="0"></td>
</table>
<P>
<A NAME="ac3d">
<H4>Review: The AC3D Modeller</H4>
</A>
<BR>
&nbsp; &nbsp; &nbsp;
There are only a few 3D modellers available for Linux: AMAPI (which may
now only be available for the Mac, based on one report I've received),
Midnight Modeller, SCED/SCEDA, and AC3D. Each of these has its advantages
and disadvantages. I've tried each of these at least briefly. A couple,
SCED and AC3D, I've used to actually create scenes. Lets take a quick look
at one of these - AC3D.
<table width=100%>
<tr>
<td>
&nbsp; &nbsp; &nbsp;
<A HREF="http://www.comp.lancs.ac.uk/computing/users/andy/ac3dlinux.html">AC3D</A>
comes from <A HREF="mailto:andy@comp.lancs.ac.uk">Andy Colebourne</A>. It
is a shareware modeller that comes in binary format only. It is available
for Linux, SGI's and Sun's (both SunOS and Solaris). Once registered you have access to a
private Web site from which you can download the full version of the software.
Documentation is a bit sparse (a common problem with much of the software
available for Linux, in this authors opinion), consisting of about
12 or 13 pages formatted in either HTML or Postscript. The distribution
package contains the binary, the HTML manual with a few images and a set
of object files that are necessary for packages which use the Mesa Graphics
Library, which AC3D does.
<td>
<IMG SRC=../gx/hammel/ac3d.jpg ALT="AC3D" ALIGN="left"
HSPACE="0" WIDTH="322" HEIGHT="248">
<BR clear=both>
<CENTER>
<B>Figure 1</B>: Example AC3D session (this is taken from the AC3D Web site).
</CENTER></td>
</table>
<BR>
&nbsp; &nbsp; &nbsp;
The interface consists of 4 view windows and a control panel. There are 3
orthographic views and a 3D view. Changes in one of the orthographic view
windows are reflected in the other views. Edits are not allowed in the 3D
view. The 3D view can provide wireframe, filled or textured surfaces.
My system is not quite fast enough to handle anything but the wireframe
surface so I won't be able to say much about the texturing features of
the modeller.
<BR>
&nbsp; &nbsp; &nbsp;
AC3D supports a number of import file formats, including DXF and Lightwave
files. It can export POV, RIB, VRML and a couple of other formats. Since
the modeller is a based on vertices (as opposed to primitives like spheres
or boxes) it is quite easy to manipulate basic shapes into more complex
ones. This can be a disadvantage to those used to the CSG aspects of SCED
or users of POV-Ray, but it really doesn't take that long to get used to.
Even though the modeller bases its shapes on vertices, there are still a
collection of basic shapes provided: disk, line, box, sphere, and mesh are
just some of these. These shapes are displayed with a given number of
vertices. The number of vertices can be configured and its possible to add
more vertices where necessary.
<BR>
&nbsp; &nbsp; &nbsp;
<table width=100%>
<tr>
<td>
&nbsp; &nbsp; &nbsp;
One of the nicest features is the ability to extrude a 2D shape into 3
dimensions. Lets follow an example of this. First, select the "ellipse"
drawing function from the control panel and create a stretched out ellipse
in the XY orthographic view.
<td>
<CENTER>
<IMG SRC=./gx/hammel/wing-1b.jpg ALT="AC3D" ALIGN="middle"
HSPACE="5" WIDTH="341" HEIGHT="279">
<BR clear=both>
<B>Figure 2</B>: An ellipse
</CENTER>
<tr>
<td>
&nbsp; &nbsp; &nbsp;
Next, change the <I>Edit</I> type to "vertex" in the control panel and select all
the vertices on the lower half of the ellipse (but not the ones on the end
of the ellipse). Delete these with the "delete" function in the control
panel. Then select the two lowest vertices and insert some new vertices (as
shown in Figure 3).
<td>
<CENTER>
<IMG SRC=./gx/hammel/wing-2b.jpg ALT="AC3D" ALIGN="middle"
HSPACE="5" WIDTH="341" HEIGHT="279">
<BR clear=both>
<B>Figure 3</B>: The ellipse has been halved and some new vertices added.
</CENTER>
</td>
<tr>
<td>
&nbsp; &nbsp; &nbsp;
This next part is a little tricky. What you want to do is select the
vertices on each end of the object and move them, one at a time, until you
get a slightly rounded effect. Then select 4 or 5 of the vertices on the
back end (the left side in Figure 4) and strecth them out a little, to
flatten the wings trailing edge. Then get rid of the extra vertices along
the bottom of the wings edge by selecting them and using the "delete"
function in the control panel. The result should look something like
Figure 4.
<td>
<CENTER>
<IMG SRC=./gx/hammel/wing-3b.jpg ALT="AC3D" ALIGN="middle"
HSPACE="5" WIDTH="341" HEIGHT="279">
<BR clear=both>
<B>Figure 4</B>: The wing edge takes shape
</CENTER>
</td>
<tr>
<td>
&nbsp; &nbsp; &nbsp;
This isn't bad, but a wing should be smoother around the top and edges,
so change the <I>Edit</I> type to "Object" and select the wing. Then
use the "Spline Surfaces" option from the <I>Object</I> pull-down menu.
This adds a bunch of new vertices to the object and creates a smoother
line around the wing.
<td>
<CENTER>
<IMG SRC=./gx/hammel/wing-4b.jpg ALT="AC3D" ALIGN="middle"
HSPACE="5" WIDTH="341" HEIGHT="279">
<BR clear=both>
<B>Figure 5</B>: Smoothing the wing edge.
</CENTER>
</td>
<tr>
<td>
&nbsp; &nbsp; &nbsp;
Now lets take this simple shape and extrude it. Make sure the
<I>Edit</I> type is still "Object" and select the wing edge. We need
to change to the XZ orthographic view window. Up to this point we've
been using the XY viewport. Click on "Extrude" under the <I>Mouse</I>
options in the control panel. Grab the object in the XZ viewport and
drag up. The original points stay put and a new set of points is moved
to where ever you drag to. Once you let go of the mouse button you'll
see the new points get connected to their corresponding points on the
original object. Notice how the connecting lines aren't quite straight.
This would be bad for a real wing, so we'll straighten them out.
<td>
<CENTER>
<IMG SRC=./gx/hammel/wing-5b.jpg ALT="AC3D" ALIGN="middle"
HSPACE="5" WIDTH="341" HEIGHT="279">
<BR clear=both>
<B>Figure 6</B>: The wing edge gets extruded.
</CENTER>
</td>
<tr>
<td>
&nbsp; &nbsp; &nbsp;
In this next figure, the control panel was used to change the
<I>Edit</I> mode to "vertices" and the vertices on the
new side of the extruded object
have been selected. Once selected, the "move" option under the
<I>Mouse</I> features allows the selected vertices to be moved as a
group. When these vertices are moved the lines connecting them to the
opposite end are redrawn. You can play with this a bit in order to get the
connecting lines to become straight. Note that its not absolutely
necessary to correctly align the two ends of the extruded object, but this
is one way to do so if you feel it necessary.
<td>
<CENTER>
<IMG SRC=./gx/hammel/wing-6b.jpg ALT="AC3D" ALIGN="middle"
HSPACE="5" WIDTH="341" HEIGHT="279">
<BR clear=both>
<B>Figure 7</B>: The ends of the extruded object are aligned.
</CENTER>
</td>
<tr>
<td>
&nbsp; &nbsp; &nbsp;
Now switch back to the "object" <I>Edit</I> mode and select the object.
The bounding box (in green) has handles that can be grabbed to drag
the bounding box to resize the object. Use the middle top and bottom
handles to make the object wider in the XZ view.
<td>
<CENTER>
<IMG SRC=./gx/hammel/wing-7b.jpg ALT="AC3D" ALIGN="middle"
HSPACE="5" WIDTH="341" HEIGHT="279">
<BR clear=both>
<B>Figure 8</B>: Stretch the object a bit.
</CENTER>
</td>
<tr>
<td>
&nbsp; &nbsp; &nbsp;
Next, switch back to "vertices" <I>Edit</I> mode and select the vertices
on one end of the object. Click on "Create Surface" under
<I>Functions</I> in the control panel. If the surface (as viewed in the 3D
view) does not appear solid you can select "Poly" under <I>Surface</I> to
create a solid surface to close the end of the object. Repeat this process
for the other end.
<P>
&nbsp; &nbsp; &nbsp;
Viola! You've got a solid surfaced wing, just like the one in Figure 9.
(The grid is an option for the 3D view window and not part of the image.)
Of course, this is a pretty simplistic example, but you should get the
idea of how easy it is to create shapes using AC3D. You'll need to export
the file to POV or RIB format and add some real textures to finish up the
project, of course.
<td>
<CENTER>
<IMG SRC=./gx/hammel/wing-9b.jpg ALT="AC3D" ALIGN="middle"
HSPACE="5" WIDTH="341" HEIGHT="279">
<BR clear=both>
<B>Figure 9</B>: The solid surfaced wing.
</CENTER>
</td>
</table>
<BR>
&nbsp; &nbsp; &nbsp;
When I first started examining modellers I got my hands on SCED, a nifty
modeller from Stephen Chenney. One of the nice features of SCED is that it
is constraint based - you can join objects using CSG and then constrain
them to certain points. This allows you to create an arm, for example,
that can bend only at the elbow. AC3D works similarly in that you can
rotate any set of points around a single point within one of the
orthographic views. For example, if I created an arm I could select
"Rotate" from the control panel and then use the mouse to rotate the arm
around a single point, such as the elbow, in one of the 2D view windows.
If I need it to move in 3D I need to do this type of rotation in 2 or more
of the 2D view windows. This process is a little different than SCED,
which can move objects in 3 dimensions, but the result is the same. In
fact, at times it can be a little easier to keep your bearings using
multiple rotations in 2D.
<BR>
&nbsp; &nbsp; &nbsp;
Since I've never used any of the modellers available for other systems
(such as high end modellers on SGI's or any of the modellers available for
Microsoft or Mac systems)
I can't say how well AC3D compares to them. I do know that I found the
modeller fairly easy to learn, but I tend to be more motivated than some
folks. AC3D could use some online help (whats the difference between a
"Poly" and a "Polyline", for example) and more detailed documentation in
general. It would also be nice to be able to unhide selected objects
instead of all hidden objects. Andy has told me that a new version coming
soon will include the ability to specify the exact dimensions of a selected
object or set of vertices. This is a very important feature in my eyes. I
tend to like to use modellers to create individual objets and then use the
conditional constructs of POV-Ray to position multiple copies of them, such
as trees or rocks or houses. By constraining an object to a unit size it
makes it easier to position and resize objects using POV-Ray.
<BR>
&nbsp; &nbsp; &nbsp;
Of all the modellers I've tried AC3D is probably the easiest to use. Its
ability to import formats like DXF gives it a step up on SCED, although I
really like the latter too. I don't particularly mind that you don't get
the source to AC3D since I'm mostly interested in just using the modeller
and not in developing new features for it. It would be nice if there were a
plug-in interface, but I'm not such a power user yet that I need that
feature. Aside from a lack of detailed documentation, and a few keystrokes
that are already used by fvwm, I find the AC3D modeller worth the
registration price.
<P>
<table width=100%>
<tr>
<td colspan=4 bgcolor="#000000" cellpadding=0 cellspacing=0 valign=top>
<IMG SRC=../gx/hammel/cleardot.gif ALT="indent" ALIGN="left"
HSPACE="0" WIDTH="0" HEIGHT="0"></td>
</table>
<P>
<A NAME="irtc">
<H4>more IRTC...</H4>
</A>
<BR>
&nbsp; &nbsp; &nbsp;
The contest started in earnest in May/June of 1996. The topic then was
Time and there were some stunning entries. In July/August we had fewer
entries, but the topic - Summer - was a little tougher to nail down.
In September/October we hit the jackpot with Science Fiction. Well over
200 entries were submitted for this round. Thats quite a difference from
the 20-30 submitted during Matt's original contests. Fortunately much of
the work for viewing, voting, and tabulating information has been
automated. The contest has been great fun and has been accompanied with
lively discussions on the associated irtc-l mailing list.
<BR>
&nbsp; &nbsp; &nbsp;
Unfortunately, there are always those that have to try to ruin things
for everyone else. We had some people submit images that were fair but not
likely winners. They then submitted multiple votes. A vote consists of
ratings of all the images with values between 1-20 for each in 3
categories - needless to say
this takes awhile to accomplish. Any vote that does not include ratings
for all images is not counted in the final tally. The multiple votes were
done offline (which is permissable) and submitted from different email
accounts. The artists images received very high marks while all the rest
received very low (within a very small range) ratings. Then they got some
of their friends to do the same thing. Beyond this, others have
submitted numerous entries that they had made in the past (prior to
the contest) that just happen to fit the category (how many 3D artists, for
fun or profit, have *never* made a space scene?) in order to turn the
contest into their own private gallery. The spirit of the competition is
lost on some people, I'm afraid.
<BR>
&nbsp; &nbsp; &nbsp;
I haven't done any of the automation nor have I worked on the very
nice web site for the contest. But I've watched Chip and Bill do so.
Its very frustrating knowing how much effort they put into this,
trying very hard not to give themselves or anyone else unfair advantages
and still make the contest fun for everyone only to see someone still try
to cheat the system. Why? For a couple of CDs? Remember when the
Internet was a friendly, honest place?
<BR>
&nbsp; &nbsp; &nbsp;
Still, the contest continues and the Admin Team is working on ways
of keeping the contest fun, open to participation, and fair. The
guys could use a new host for their contest. Walnut Creek, the current
host, appears to be limiting ftp connections and the amount of disk space
required for 200+ images can get rather large.
<BR>
&nbsp; &nbsp; &nbsp;
If you are into 3D rendering for the fun of it you owe it to yourself
to take a shot at the IRTC. Its fun to see how your images stack
up against others. Many of the voters offer comments on the images which
can very useful in any future images you render. Check our the
<A HREF="http://www.povray.org/irtc/">IRTC Web Site</A>
to get more details and join in!
<P>
<table width=100%>
<tr>
<td colspan=4 bgcolor="#000000" cellpadding=0 cellspacing=0 valign=top>
<IMG SRC=../gx/hammel/cleardot.gif ALT="indent" ALIGN="left"
HSPACE="0" WIDTH="0" HEIGHT="0"></td>
</table>
<table width=100%>
<tr>
<td align=right>
<FONT size=1>
&copy 1996 by <A HREF="mailto:mjhammel@csn.net">Michael J. Hammel</A>
</FONT>
</table>
<!--===================================================================-->
<P> <HR> <P>
<!-- =============================================================
This Page Designed by Michael J. Hammel.
Permission to use all graphics and other content for private,
non-commerical use is granted provided you give me (or the
original authors/artists) credit for the work.
CD-ROM distributors and commercial ventures interested in
providing the Graphics Muse for a fee must contact me,
Michael J. Hammel (mjhammel@csn.net), for permission.
============================================================= !-->
<A NAME="musings">
<table>
<tr>
<td>
<H2>More...</H2>
<BR clear=both>
<IMG SRC=../gx/hammel/musings.gif ALT="Musings" ALIGN="left"
HSPACE="0" VSPACE="0" WIDTH="247" HEIGHT="52">
</td>
</table>
</A>
<BR clear=both>
<P>
<A NAME="png">
<H4>History of the Portable Network Graphics (PNG) format</H4>
by <A HREF="mailto:newt@pobox.com">Greg Roelofs</A>
</A>
<P>
<B>Prehistory</B>
<BR>
&nbsp; &nbsp; &nbsp;
The Story of PNG actually begins way back in 1977 and 1978 when two Israeli
researchers, Jacob Ziv and Abraham Lempel, first published a pair of papers on
a new class of lossless data-compression algorithms, now collectively referred
to as ``LZ77'' and ``LZ78.'' Some years later, in 1983, Terry Welch of Sperry
(which later merged with Burroughs to form Unisys) developed a very fast
variant of LZ78 called LZW. Welch also filed for a patent on LZW, as did two
IBM researchers, Victor Miller and Mark Wegman. The result was...you guessed
it...the USPTO granted both patents (in December 1985 and March 1989,
respectively).
<BR>
&nbsp; &nbsp; &nbsp;
Meanwhile CompuServe--specifically, Bob Berry--was busily designing a new,
portable, compressed image format in 1987. Its name was GIF, for ``Graphics
Interchange Format,'' and Berry et al. blithely settled on LZW as the
compression method. Tim Oren, Vice President of Future Technology at
CompuServe (now with Electric Communities), wrote: ``The LZW algorithm
was incorporated from an open publication, and without knowledge that Unisys
was pursuing a patent. The patent was brought to our attention, much to our
displeasure, after the GIF spec had been published and passed into wide use.''
There are claims [1] that Unisys was made aware of this as early as 1989 and
chose to ignore the use in ``pure software''; the documents to substantiate
this claim have apparently been lost. In any case, Unisys for years limited
itself to pursuit of hardware vendors--particularly modem manufacturers
implementing V.42bis in silicon.
<BR>
&nbsp; &nbsp; &nbsp;
All of that changed at the end of 1994. Whether due to ongoing financial
difficulties or as part of the industry-wide bonk on the head provided by
the World Wide Web, Unisys in 1993 began aggressively pursuing commercial
vendors of software-only LZW implementations. CompuServe seems to have
been its primary target at first, culminating in an agreement--quietly
announced on 28 December 1994, right in the middle of the Christmas
holidays--to begin collecting royalties from authors of GIF-supporting
software. The spit hit the fan on the Internet the following week; what
was then the comp.graphics newsgroup went nuts, to use a technical term.
As is the way of Usenet, much ire was directed at CompuServe for making
the announcement, and then at Unisys once the details became a little
clearer; but mixed in with the noise was the genesis of an informal Internet
working group led by Thomas Boutell [2]. Its purpose was not only to design a
replacement for the GIF format, but a successor to it: better, smaller,
more extensible, and FREE.
<P>
<B>The Early Days (All Seven of 'Em)</B>
<BR>
&nbsp; &nbsp; &nbsp;
The very first PNG draft--then called ``PBF,'' for Portable Bitmap Format--
was posted by Tom to comp.graphics, comp.compression and
comp.infosystems.www.providers on Wednesday, 4 January 1995. It had a
three-byte signature, chunk numbers rather than chunk names, maximum pixel
depth of 8 bits and no specified compression method, but even at that stage
it had more in common with today's PNG than with any other existing format.
<BR>
&nbsp; &nbsp; &nbsp;
Within one week, most of the major features of PNG had been proposed, if
not yet accepted: delta-filtering for improved compression (Scott Elliott);
deflate compression (Tom Lane, the Info-ZIP gang and many others); 24-bit
support (many folks); the PNG name itself (Oliver Fromme); internal CRCs
(myself); gamma chunk (Paul Haeberli) and 48- and 64-bit support (Jonathan
Shekter). The first proto-PNG mailing list was also set up that week; Tom
released the second draft of the specification; and I posted some test results
that showed a 10% improvement in compression if GIF's LZW method was simply
replaced with the deflate (LZ77) algorithm. Figure 1 is a timeline listing
many of the major events in PNG's history.
<P>
<CENTER>
<table>
<tr>
<td colspan=3 bgcolor="#000000" cellpadding=1 cellspacing=0 valign=top>
<IMG SRC=../gx/hammel/cleardot.gif ALT="indent" ALIGN="left"
WIDTH="1" HEIGHT="1"></td>
<tr>
<td align=left> 4
<td align=center> Jan 95
<td align=left> PBF draft 1 (Thomas Boutell)
<tr>
<td align=left> 4
<td align=center> Jan 95
<td align=left> delta-filtering (Scott Elliott)
<tr>
<td align=left> 4
<td align=center> Jan 95
<td align=left> deflate compression (Tom Lane et al.)
<tr>
<td align=left> 4
<td align=center> Jan 95
<td align=left> 24-bit support (many)
<tr>
<td align=left> 5
<td align=center> Jan 95
<td align=left> TeleGrafix LZHUF proposal (same or slightly larger)
<tr>
<td align=left> 6
<td align=center> Jan 95
<td align=left> PNG name (Oliver Fromme)
<tr>
<td align=left> 7
<td align=center> Jan 95
<td align=left> PBF draft 2 (Thomas Boutell)
<tr>
<td align=left> 7
<td align=center> Jan 95
<td align=left> ZIF early results (Greg Roelofs)
<tr>
<td align=left> 7
<td align=center> Jan 95
<td align=left> internal CRC(s) (Greg Roelofs)
<tr>
<td align=left> 8
<td align=center> Jan 95
<td align=left> gamma chunk (Paul Haeberli)
<tr>
<td align=left> 8
<td align=center> Jan 95
<td align=left> 48-, 64-bit support (Jonathan Shekter)
<tr>
<td align=left> 9
<td align=center> Jan 95
<td align=left> FGF proposal, implementation (Jeremy Wohl)
<tr>
<td align=left> 10
<td align=center> Jan 95
<td align=left> first NGF/PBF/proto-PNG mailing list (Jeremy Wohl)
<tr>
<td align=left> 15
<td align=center> Jan 95
<td align=left> PBF draft 3 (Thomas Boutell)
<tr>
<td align=left> 16
<td align=center> Jan 95
<td align=left> CompuServe announces GIF24 development (Tim Oren)
<tr>
<td align=left> 16
<td align=center> Jan 95
<td align=left> spec available on WWW (Thomas Boutell)
<tr>
<td align=left> 16
<td align=center> Jan 95
<td align=left> PBF draft 4 (Thomas Boutell)
<tr>
<td align=left> 23
<td align=center> Jan 95
<td align=left> PNG draft 5 (Thomas Boutell)
<tr>
<td align=left> 24
<td align=center> Jan 95
<td align=left> PNG draft 6 (Thomas Boutell)
<tr>
<td align=left> 26
<td align=center> Jan 95
<td align=left> final 8-byte signature (Tom Lane)
<tr>
<td align=left> 1
<td align=center> Feb 95
<td align=left> PNG draft 7 (Thomas Boutell)
<tr>
<td align=left> 2
<td align=center> Feb 95
<td align=left> Adam7 interlacing scheme (Adam Costello)
<tr>
<td align=left> 7
<td align=center> Feb 95
<td align=left> CompuServe announces PNG == GIF24 (Tim Oren)
<tr>
<td align=left> 13
<td align=center> Feb 95
<td align=left> PNG draft 8 (Thomas Boutell)
<tr>
<td align=left> 7
<td align=center> Mar 95
<td align=left> PNG draft 9 (Thomas Boutell)
<tr>
<td align=left> 11
<td align=center> Mar 95
<td align=left> first working PNG viewer (Oliver Fromme)
<tr>
<td align=left> 13
<td align=center> Mar 95
<td align=left> first valid PNG images posted (Glenn Randers-Pehrson)
<tr>
<td align=left> 1
<td align=center> May 95
<td align=left> pnglib 0.6 released (Guy Eric Schalnat)
<tr>
<td align=left> 1
<td align=center> May 95
<td align=left> zlib 0.9 released (Jean-loup Gailly, Mark Adler)
<tr>
<td align=left> 5
<td align=center> May 95
<td align=left> PNG draft 10 (Thomas Boutell)
<tr>
<td align=left> 13
<td align=center> Jun 95
<td align=left> PNG home page (Greg Roelofs)
<tr>
<td align=left> 8
<td align=center> Dec 95
<td align=left> PNG spec 0.92 released as W3C Working Draft
<tr>
<td align=left> 23
<td align=center> Feb 96
<td align=left> PNG spec 0.95 released as IETF Internet Draft
<tr>
<td align=left> 28
<td align=center> Mar 96
<td align=left> deflate and zlib approved as Informational RFCs (IESG)
<tr>
<td align=left> 22
<td align=center> May 96
<td align=left> deflate and zlib released as Informational RFCs (IETF)
<tr>
<td align=left> 1
<td align=center> Jul 96
<td align=left> PNG spec 1.0 released as W3C Proposed Recommendation
<tr>
<td align=left> 11
<td align=center> Jul 96
<td align=left> PNG spec 1.0 approved as Informational RFC (IESG)
<tr>
<td align=left> 4
<td align=center> Aug 96
<td align=left> VRML 2.0 spec released with PNG as requirement (VAG)
<tr>
<td align=left> 1
<td align=center> Oct 96
<td align=left> PNG spec 1.0 approved as W3C Recommendation
<tr>
<td align=left> 14
<td align=center> Oct 96
<td align=left> image/png approved (IANA)
<tr>
<td colspan=3 bgcolor="#000000" cellpadding=1 cellspacing=0 valign=top>
<IMG SRC=../gx/hammel/cleardot.gif ALT="indent" ALIGN="left"
WIDTH="1" HEIGHT="1"></td>
<tr>
<td colspan=3 align=center> <B>Figure 1</B>: a PNG timeline
</table>
</CENTER>
<BR>
&nbsp; &nbsp; &nbsp;
Perhaps equally interesting are some of the proposed features and design
suggestions that ultimately were <I>not</I> accepted: the Amiga IFF format;
uncompressed bitmaps either gzip'd or stored inside zipfiles; thumbnail
images and/or generic multi-image support; little-endian byte order; Unicode
UTF-8 character set for text; YUV and other lossy image-encoding schemes; and
so forth. Many of these topics produced an amazing amount of discussion--in
fact, the main proponent of the zipfile idea is still making noise two years
later.
<P>
<B>Onward, Frigidity</B>
<BR>
&nbsp; &nbsp; &nbsp;
One of the real strengths of the PNG group was its ability to weigh the pros
and cons of various issues in a rational manner (well, most of the time,
anyway), reach some sort of consensus and then move on to the next issue
without prolonging discussion on ``dead'' topics indefinitely. In part this
was probably due to the fact that the group was relatively small, yet possessed
of a sufficiently broad range of graphics and compression expertise that no
one felt unduly ``shut out'' when a decision went against him. (All of the
PNG authors were male. Most of them still are. I'm sure
there's a dissertation in there somewhere...) But equally important was Tom
Boutell, who, as the initiating force behind the PNG project, held the role
of benevolent dictator--much the way Linus Torvalds does with Linux kernel
development. When consensus was impossible, Tom would make a decision, and
that would settle the matter. (On one or two rare occasions he might later
have been persuaded to reverse the decision, but this generally only happened
if new information came to light.)
<BR>
&nbsp; &nbsp; &nbsp;
In any case, the development model worked: by the beginning of February 1995,
seven drafts had been produced, and the PNG format was settling down. (The
PNG name was adopted in Draft 5.) The next month was mainly spent working
out the details: chunk-naming conventions, CRC size and placement, choice
of filter types, palette-ordering, specific flavors of transparency and
alpha-channel support, interlace method, etc. CompuServe was impressed
enough by the design that on the 7th of February they announced support for
PNG as the designated successor to GIF, supplanting what they had initially
referred to as the GIF24 development project. [3] By the beginning of March,
PNG Draft 9 was released and the specification was officially frozen--just
over two months from its inception. Although further drafts followed, they
merely added clarifications, some recommended behaviors for encoders and
decoders, and a tutorial or two. Indeed, Glenn Randers-Pehrson has kept some
so-called ``paleo PNGs'' that were created at the time of Draft 9; they are
still readable by any PNG decoder today. [4]
<P>
<B>Oy, My Head Hurts</B>
<BR>
&nbsp; &nbsp; &nbsp;
But specifying a format is one thing; implementing it is quite another.
Although the original intent was to create a "lightweight" format--and,
compared to TIFF or even JPEG, PNG <I>is</I> fairly lightweight--even a
completely orthogonal feature set can introduce substantial complications.
For example, consider progressive display of an image in a web browser.
First comes straight decoding of the compressed data; no problems there.
Then any line-filtering must be inverted to get the actual image data.
Oops, it's an interlaced image: now pixels are appearing here and
there within each 8x8 block, so they must be rendered appropriately (and
possibly buffered). The image also has transparency and is being overlaid
on a background image, adding a bit more complexity. So far we're not much
worse off than we would be with an interlaced, transparent GIF; the line
filters and 2D interlacing scheme are pretty straightforward extensions to
what programmers have already dealt with. Even adding gamma correction to
the foreground image isn't too much trouble.
<BR>
&nbsp; &nbsp; &nbsp;
But wait, it's not just simple transparency; we have an alpha channel! And
we don't want sparse display--we really like the replicating progressive
method Netscape Navigator uses. Now things are tricky: each replicated
pixel-block has some percentage of the fat foreground pixel mixed in with
complementary amounts of the background pixels in the block. And just
because the current fat pixel is 65% transparent (or, even worse, completely
opaque) doesn't mean later ones in the same block will be, too: thus we have
to remember all of the original background pixel-values until their final
foreground pixels are composited and overlaid. Toss in the ability to render
all of this nicely on an 8-bit, colormapped display, and most programmers'
heads will explode.
<P>
<B>Make It So!</B>
<BR>
&nbsp; &nbsp; &nbsp;
Of course, some of these things are application (presentation or front-end)
issues, not general PNG-decoding (back-end) issues. Nevertheless, a good
PNG library should allow for the possibility of such applications--which is
another way of saying that it should be general enough not to place undue
restrictions on any programmer who wants to implement such things.
<BR>
&nbsp; &nbsp; &nbsp;
Once Draft 9 was released, many people set about writing PNG encoders
and/or decoders. The true glory is really reserved for three people,
however: Info-ZIP's Jean-loup Gailly and Mark Adler (both also of gzip fame),
who originally wrote Zip's deflate() and UnZip's inflate() routines and
then, for PNG, rewrote them as a portable library called <I>zlib</I> [5]; and Guy
Eric Schalnat of Group 42, who almost single-handedly wrote the <I>libpng</I>
reference implementation (originally ``pnglib'') from scratch. [6] The
first truly usable versions of the libraries were released two months after
Draft 9, on the first of May, 1995. Although both libraries were missing
some features required for full implementation, they were sufficiently
complete to be used in various freeware applications. (Draft 10 of the
specification was released at the same time, with clarifications resulting
from these first implementations.)
<P>
<B>Fast-Forward to the Present</B>
<BR>
&nbsp; &nbsp; &nbsp;
The pace of subsequent developments slowed at that point. This was partly
due to the fact that, after four months of intense development and dozens of
e-mail messages every day, everyone was burned out; partly because Guy
controlled libpng's development and became busy with other things at work;
and partly because of the perception that PNG was basically ``done.'' The
latter point was emphasized by a CompuServe press release to that effect in
mid-June (and one, I might add, in which their PR guys claimed much of the
credit for PNG's development, sigh).
<BR>
&nbsp; &nbsp; &nbsp;
Nevertheless, progress continued. In June of 1995 I set up the PNG home page,
now grown to roughly a dozen pages [7]; Kevin Mitchell officially registered
the ``PNGf'' Macintosh file ID with Apple Computer. In August Alexander
Lehmann and Willem van Schaik released a fine pair of additions to the NetPBM
image-manipulation suite, particularly handy under Linux: pnmtopng and
pngtopnm version 2.0. And in December at the Fourth International World Wide
Web Conference, the World Wide Web Consortium (W3C) released the PNG
Specification version 0.92 as an official standards-track Working Draft.
<BR>
&nbsp; &nbsp; &nbsp;
1996 saw the February release of version 0.95 as an Internet Draft by the
Internet Engineering Task Force (IETF), followed in July by the Internet
Engineering Steering Group's (IESG) approval of version 1.0 as an official
Informational RFC. (However, the IETF secretary still hasn't issued the
actual RFC number at the time of this writing, five months later. Sigh.)
The Virtual Reality Modeling Language (VRML) Architecture Group in early
August adopted PNG as one of the two required image formats for minimal
VRML 2.0 conformance. [8] Meanwhile the W3C promoted the spec to Proposed
Recommendation status in July and then to full Recommendation status on the
first of October. [9] Finally, in mid-October the Internet Assigned Numbers
Authority (IANA) formally approved ``image/png'' as an official Internet
Media Type, joining image/gif and image/jpeg as non-experimental image
formats for the Web. Much of this standardization would not have happened
nearly as quickly without the tireless efforts of Tom Lane and Glenn
Randers-Pehrson, who took over editing duties of the spec from Thomas Boutell.
<P>
<B>Current Status</B>
<BR>
&nbsp; &nbsp; &nbsp;
So where are we today? The future is definitely bright for PNG, and the
present isn't looking too bad, either. I now have over 125 applications
listed [10] with PNG support either current or planned (mostly current);
among the ones available for Linux are:
<UL>
<LI>XV (image viewer/converter)
<LI>ImageMagick (image viewer/converter)
<LI>GRAV (image viewer)
<LI>Zgv (image viewer)
<LI>xli (image viewer)
<LI>XPaint (image editor)
<LI>The GIMP (image editor)
<LI>Image Alchemy (image converter)
<LI>pnmtopng/pngtopnm (image converters)
<LI>XEmacs (editor/web browser/operating system/etc.)
<LI>gforge (fractal terrain generator)
<LI>Fractint (fractal generator)
<LI>Ghostscript (PostScript viewer/converter)
<LI>GNUplot (plotting program)
<LI>PV-WAVE (scientific visualization program)
<LI>POV-Ray (ray-tracer)
<LI>VRweb (VRML browser)
<LI>X Mosaic (web browser)
<LI>Arena (web browser)
<LI>Chimera (web browser)
<LI>Grail (web browser)
<LI>Amaya (web browser/editor)
<LI>Mapedit (image-map editor)
<LI>WWWis (HTML IMG sizer)
<LI>file(1) (Unix file-type identifier)
</UL>
<BR>
&nbsp; &nbsp; &nbsp;
Discerning readers will note the conspicuous absence of Netscape Navigator.
Despite the fact that Netscape was aware of the PNG project from the
beginning and unofficially indicated ``probable support''; despite the nice
benefits gamma correction, alpha support and 2D interlacing bring to WWW
applications; despite the fact that the WWW Consortium, of which Netscape is
a member, released the PNG spec as its first official Recommendation; despite
the requirement to support PNG in VRML 2.0 viewers like Netscape's own Live3D
plug-in; and despite considerable pestering by members of the PNG group and
the Internet community at large, Netscape is still only ``considering'' future
support of PNG. Until Netscape either supports PNG natively or gets swept
away by Microsoft or someone else, PNG's usefulness as an image format for
the Web is considerably diminished.
<BR>
&nbsp; &nbsp; &nbsp;
On the other hand, our buds at Microsoft recognized the benefits of PNG and
apparently embraced it wholeheartedly. They have not only made it the native
image format of the Office97 application suite but have also repeatedly
promised to put it into Internet Explorer (theoretically by the time of the
4.0 betas--we'll see about that). Assuming they do, Netscape is almost
certain to follow suit. (See? Microsoft <I>is</I> good for something!) At
that point PNG should enjoy a real burst of WWW interest and usage.
<BR>
&nbsp; &nbsp; &nbsp;
In the meantime, PNG viewing actually is possible with Linux Netscape; it's
just not very useful. Rasca Gmelch is working on a Unix plug-in with (among
other things) PNG support. Although it's still an alpha version and requires
ImageMagick's <B>convert</B> utility to function, that's not the problem; Netscape's
brain-damaged plug-in architecture is. Plug-ins have no effect on HTML's
IMG tag: if there's no native support for the image format and no helper
app defined, the image is ignored regardless of whether an installed plug-in
supports it. Instead you must use Netscape's EMBED extension. That means
anyone who wants universally viewable web pages loses either way: PNG with
IMG doesn't work under Netscape, and PNG with EMBED doesn't work under much
of anything except Netscape and MSIE (and those only if the user has installed
a working PNG plug-in).
<BR>
&nbsp; &nbsp; &nbsp;
But support by five or six other Linux web browsers ain't bad, and even
mainstream applications like Adobe's Photoshop now do PNG natively. More
are showing up every week, too. Life is good.
<P>
<B>The Future</B>
<BR>
&nbsp; &nbsp; &nbsp;
As VRML takes off--which it almost certainly will, especially with the
advent of truly cheap, high-performance 3D accelerators--PNG will go along
for the ride. (JPEG, which is the other required VRML 2.0 image format,
doesn't support transparency.) Graphic artists will use PNG as an intermediate
format because of its lossless 24-bit (and up) compression and as a final
format because of its ability to store gamma and chromaticity information for
platform-independence. Once the ``big-name'' browsers support PNG natively,
users will adopt it as well--for the 2D interlacing method, the cross-platform
gamma correction, and the ability to make anti-aliased balls, buttons, text
and other graphic elements that look good on *any* color background (no more
``ghosting,'' thanks to the alpha-channel support).
<BR>
&nbsp; &nbsp; &nbsp;
Indeed, the only open issue is support for animations and other multi-image
applications. In retrospect, the principal failure of the PNG group was its
delay in extending PNG to MNG, the "Multi-image Network Graphics" format.
As noted earlier, everyone was pretty burned out by May 1995; in fact, it
was a full year before serious discussion of MNG resumed. As (bad) luck
would have it, October 1995 is when the first Netscape 2.0 betas arrived
with animation support, giving the (dying?) GIF format a huge resurgence
in popularity.
<BR>
&nbsp; &nbsp; &nbsp;
At the time of this writing (mid-December 1996), the MNG specification has
undergone some 27 drafts--almost entirely written by Glenn Randers-Pehrson--and
is close to being frozen. A couple of special-purpose MNG implementations have
been written, as well. But MNG is too late for the VRML 2.0 spec, and despite
some very compelling features, it may never be perceived as anything more than
PNG's response to GIF animations. Time will tell.
<P>
<B>At Last...</B>
<BR>
&nbsp; &nbsp; &nbsp;
It's always difficult for an insider to render judgment on a project like
PNG; that old forest-versus-trees thing tends to get in the way of objectivity.
But it seems to me that the PNG story, like that of Linux, represents the
best of the Internet: international cooperation, rapid development and the
production of a Good Thing that is not only useful but also freely available
for everyone to enjoy.
<BR>
&nbsp; &nbsp; &nbsp;
Then again, maybe I'm just a shameless egotist (nyuk nyuk nyuk). You
decide....
<P>
<B>Acknowledgments</B>
<BR>
&nbsp; &nbsp; &nbsp;
I'd like to thank Jean-loup Gailly for his excellent comp.compression FAQ,
which was the source for much of the patent information given above. [11]
Thanks also to Mark Adler and JPL, who have been the fine and generous hosts
for the PNG home pages, zlib home pages, Info-ZIP home pages and my own,
personal home pages. (Through no fault of Mark's, that will all
come to an end as of the new year; oddly enough, JPL has decided that none
of it is particularly relevant to planetary research. Go figure.)
<P>
<B>References</B>
<table>
<tr>
<td valign=top> [1]
<td valign=top>
Raymond Gardner, rgardner@teal.csn.org, 8 Jan 1995 23:11:58 GMT,
comp.graphics/comp.compression, Message-ID <3eprfu$jqs@news-2.csn.net>.
See also Michael Battilana's article discussing the legal history of the
GIF/LZW controversy:
<BR>
&nbsp; &nbsp; &nbsp;
<A HREF="http://www.cloanto.com/users/mcb/19950127giflzw.html"
>http://www.cloanto.com/users/mcb/19950127giflzw.html</A>
<tr>
<td valign=top> [2]
<td valign=top> <A HREF="http://www.boutell.com/boutell/"
>http://www.boutell.com/boutell/</A>
<tr>
<td valign=top> [3]
<td valign=top> <A HREF="http://www.w3.org/pub/WWW/Graphics/PNG/CS-950214.html"
>http://www.w3.org/pub/WWW/Graphics/PNG/CS-950214.html</A>
<tr>
<td valign=top> [4]
<td valign=top> <A HREF="http://www.rpi.edu/~randeg/paleo_pngs.html"
>http://www.rpi.edu/~randeg/paleo_pngs.html</A>
<tr>
<td valign=top> [5]
<td valign=top> <A HREF="http://quest.jpl.nasa.gov/zlib/"
>http://quest.jpl.nasa.gov/zlib/</A>
<tr>
<td valign=top> [6]
<td valign=top> <A HREF="ftp://swrinde.nde.swri.edu/pub/png/src/"
>ftp://swrinde.nde.swri.edu/pub/png/src/</A>
<tr>
<td valign=top> [7]
<td valign=top> <A HREF="http://quest.jpl.nasa.gov/PNG/"
>http://quest.jpl.nasa.gov/PNG/</A>
(but probably moved to
<A HREF="http://www.wco.com/~png/">http://www.wco.com/~png/</A>
by 1 January 1997)
<tr>
<td valign=top> [8]
<td valign=top> <A HREF="http://vag.vrml.org/VRML2.0/FINAL/spec/part1/conformance.html"
>http://vag.vrml.org/VRML2.0/FINAL/spec/part1/conformance.html</A>
<tr>
<td valign=top> [9]
<td valign=top> <A HREF="http://www.w3.org/pub/WWW/TR/REC-png.html"
>http://www.w3.org/pub/WWW/TR/REC-png.html</A>
<tr>
<td valign=top> [10]
<td valign=top> <A HREF="http://quest.jpl.nasa.gov/PNG/pngapps.html"
>http://quest.jpl.nasa.gov/PNG/pngapps.html</A>
<tr>
<td valign=top> [11]
<td valign=top> <A HREF="http://www.cis.ohio-state.edu/hypertext/faq/usenet/compression-faq/top.html"
>http://www.cis.ohio-state.edu/hypertext/faq/usenet/compression-faq/top.html</A>
</table>
<table width=100%>
<tr>
<td colspan=4 bgcolor="#000000" cellpadding=0 cellspacing=0 valign=top>
<IMG SRC=../gx/hammel/cleardot.gif ALT="indent" ALIGN="left"
HSPACE="0" WIDTH="0" HEIGHT="0"></td>
</table>
<table width=100%>
<tr>
<td align=right>
<FONT size=1>
&copy 1996 by <A HREF="mailto:mjhammel@csn.net">Michael J. Hammel</A>
</FONT>
</table>
<!--===================================================================-->
<P> <HR> <P>
<H4>
&quot;Linux Gazette...<I>making Linux just a little more fun!</I>
&quot;</H4>
<P> <HR> <P>
<!--===================================================================-->
<center>
<H1>Indexing Texts with Smart</H1>
<H4>By Hans Paijmans
<a href="mailto:paai@kub.nl">paai@kub.nl</a></H4>
</center>
<P> <HR> <P>
<H2>1. The uses of Linux and MS-DOS</A></H2>
<P>
Although my colleagues here on Tilburg University may think that I
spend my time fiddling with Linux on a PC that could be put to better
uses, they are wrong. The 'fiddling with Linux' I do at home; at my
work I only do the bare minimum necessary to keep Linux fed and happy.
As most readers of this journal know, this involves making the
occasional backup and for the rest: nothing.
<P>
When I sit in front of my PC, I <EM>work</EM> (well, mostly). Linux makes
it possible to do my work with a minimum of fuss and a big part of the
credit for this goes to Jacques Gelinas, the man who wrote Umsdos: a
layer between the Unix operating system and the vanilla MS-DOS 8+3 FAT
system. This makes it possible to access the DOS-partition of my hard
disk from either operating system. This is good news, because I am
totally dependent from two programs: SMART, an indexing and retrieval
system and SPSS for Windows to twiddle the data I obtain form
SMART. SMART only runs under Unix (and not all Unixes for that matter)
and SPSS4Windows, obviously, runs under MS-Windows and whatever the
virtues of this operating system may be, you emphatically do not want
to use it in any kind of experimental environment.
<P>
I suppose that SPSS (Statistical Package for the Social Sciences) will
be familiar to most Linux users. If not: SPSS is just what it says, a
statistical package but not only for the 'social sciences' but for
about everyone who needs statistical analysis of his data. SMART,
however, is an indexing and retrieval program for text. What is more:
it does not just index the words, it also adds weights to them. It
also allows the user to compare the indexed documents in the so-called
Vector Space Model and to compute the distances between the documents,
or between documents and queries. To understand why this is special we
must delve a bit in the typical problems of Information Retrieval,
i.e. the storage of books, articles etcetera and the retrieval of
those on content.
<P>
<H2><A NAME="SECTION00011000000000000000">1.1 Why indexing is not enough</A></H2>
<P>
When at the end of the sixties automatic indexing of texts became a
viable option many people thought that the problems of information
retrieval were solved. Programs like STAIRS (IBM,1972)
enabled the users to file and rapidly retrieve documents on any word
in the text or on boolean combinations (AND, OR, NOT) of those words
and who could ask for more? Then, in 1985 a famous article was
published by two researchers in the field [<A HREF="#BlairMaron1985">1</A>]. In
this article they reported on the performance of STAIRS in real life
and they showed that the efficiency of STAIRS and similar systems was,
in fact, much lower than assumed. Even experienced users could not obtain a
recall of more than 20-40% of the relevant documents in a database of
100,000 documents, and worse, they were not aware of the fact.<BR>
<P>
The problem with all retrieval systems of this type is that human
language is so fuzzy. There may be as much as a dozen different terms
and words pointing to one and the same object, whereas one word may
have widely different meanings. In Information Retrieval this will
lead to one of two situations. Either you try to obtain a high
precision, when almost all the retrieved documents are relevant (but
an unknown number of other relevant documents are not included) or you
go for high recall, but then a lot of irrelevant documents will be
included in the result. When in a retrieved set of documents the
proportion of irrelevant documents is high, the user will probably
stop looking at the documents before he or she has found all the
relevant ones: in fact his <EM>futility-point</EM> has been reached. In
such a case the net result is equal to the situation in which those
relevant records that would be presented after the user reached that
futility-point were <EM>not</EM> retrieved. Therefore the concept of
ranking, i.e. the ordering of retrieved documents on relevance, is
very important in Information Retrieval.
<P>
<H2><A NAME="SECTION00020000000000000000">2. SMART</A></H2>
<P>
Modern (and not so modern) research has offered a number of possible
solutions to this dilemma. Some of those solutions use the concept of
<EM>weighted</EM> keywords. This means that every keyword-document
combination has a weight attached that (hopefully) is an indication of
the relevance of that particular keyword for that particular
document. SMART does just that: it creates indexes for a database of
documents and attaches weights to them. The way that happens may be
expressed intuitively as <EM>'the more a word occurs in the less
documents, the higher the weight'</EM>. Or, if the word 'dog' occurs
twenty times in a given document, but in no other documents, you may
be relatively certain that this document is about dogs. Information
Retrieval addicts like me talk about the <I>tf</I>.<I>idf</I> weight.
<P>
Smart offers several options as to how that weight should be arrived
at: I generally prefer the so-called atc-variation, because it adjusts
for the length of the individual documents.
<P>
It calculates the <I>tf</I>.<I>idf</I> in three steps. The first step creates the
value <IMG WIDTH=35 HEIGHT=18 ALIGN=MIDDLE ALT="tex2html_wrap_inline96" SRC="./gx/hansp/img1.gif" > for the term-frequency (<I>tf</I>) as
<P>
<P> <IMG WIDTH=321 HEIGHT=27 ALIGN=BOTTOM ALT="displaymath86" SRC="./gx/hansp/img2.gif" > <P>
<P>
where <IMG WIDTH=37 HEIGHT=18 ALIGN=MIDDLE ALT="tex2html_wrap_inline100" SRC="./gx/hansp/img3.gif" > is the term with the highest frequency in the
document. This adjusts for the document-length and the number of
terms. Then the weight <IMG WIDTH=37 HEIGHT=7 ALIGN=BOTTOM ALT="tex2html_wrap_inline102" SRC="./gx/hansp/img4.gif" > is calculated as
<P>
<P> <IMG WIDTH=313 HEIGHT=26 ALIGN=BOTTOM ALT="displaymath87" SRC="./gx/hansp/img5.gif" > <P>
<P>
where N is as before the number of documents and <I>F</I> the document
frequency of term <I>t</I> (the number of documents in which term <I>t</I>
occurs). Finally the cosine normalization is applied by
<P>
<P> <IMG WIDTH=318 HEIGHT=35 ALIGN=BOTTOM ALT="displaymath88" SRC="./gx/hansp/img6.gif" > <P>
<P>
where T is the number of terms in the document vector. Now we have a
number between zero and one that hopefully correlates with the
importance of the word as a keyword for that document. For a
detailed discussion of these and similar techniques see e.g. Salton
and McGill ([<A HREF="#SaltonMcGill1983">2</A>]). You will love it!
<P>
This is not all. When SMART has constructed the index in one of the
various ways available, it also can retrieve the documents for
you. This is done according to something called ``the Vector Space
Model''. This model is best explained using a three-dimensional
example of a vector-space; you can add another few thousand dimensions
in your own imagination.
<P>
Imagine you want to index your documents according to three keywords
'cat', 'dog' and 'horse'; keywords that may or may not occur in your
documents. So you draw three axes to get a normal three-dimensional
coordinate system. One dimension can be used to indicate the
``cat-ness'' of every document, the other its ``dog-ness'' and the
third the ``lion-ness''. To make things easy we only use binary values
0 and 1, although SMART can cope with floats (the 'weights' mentioned
before. So if a document is about cats, it scores a one on the
corresponding axis, otherwise it scores a zero. Any document may now
be drawn in that space according to the occurrence of one or more of
the keywords and now we have a relatively easy way to compute the
difference between those document. Moreover a query consisting of
one or more of the keywords can be drawn in the same space and the
documents can be ranked according to the distance to that query. Of
course a typical document database has thousands of keywords and
accordingly thousands of dimensions, but the arithmetics involved in
multi-dimensional distances do not matter much to modern computers,
and if they bother <EM>you</EM>, you just have to smoke something illegal
and matters will rapidly become clear. If only till the next morning.
<P>
So SMART accepts queries, ranks the documents according to the
``nearness'' to that query and return them to you in that
order. Therefore it is still one of the best retrieval systems that
are ever written although it lacks the bells and whistles of its more
expensive counterparts in some operating systems I could mention. And
although it is not really optimized for speed, it runs typically 10-30
times faster than the fastest indexing program I ever saw under
MS-Windows.
<P>
<H2><A NAME="SECTION00030000000000000000">3. The DOS connection</A></H2>
<P>
But I am not using SMART for bread-and-butter retrieval, but for the
weights it computes and the indexes it creates. At this point I want
to do some other manipulations of these data and again I have to offer
my thanks to the developers of unix in general and to Linux in
particular. A whole string of ever more complicated and sophisticated
shell scripts, the standard unix tools and a few of My Very Own
utilities suffice to process the SMART output to a file that is ready
for importing in SPSS.
<P>
Nevertheless now I have to quit Linux and boot MS-DOS, start
MS-Windows and finally enter SPSS to do the statistics and create some
graphs. I am a newcomer to Unix (indeed it was the fact that Linux
offered a way to use SMART that pulled me over the line two years
ago), but already I am wondering how people can live in the stifling
atmosphere of MS-Windows. The fact that you can't really run two
applications at the same time is not even the worst thing. But who is
responsible for the idea that Icons and Popups were better and more
efficient than the plain old command line? And what happened to pipes
and filters? And a sensible command language? Be that as it may, SPSS
gets the job done and when the output is written to disk I immediately
escape back to Linux to write the final article, report or whatever
with LaTeX.<BR>
<P>
<H2><A NAME="SECTION00040000000000000000">4. The bad news</A></H2>
<P>
On this point I have two messages: one is good, the other bad. I'll
start with the good news. SMART is obtainable by anonymous ftp from
Cornell University and may be used for free for scientific and
experimental purposes. Better yet: it compiles under Linux without
much tweaking and twiddling. Also there exists a fairly active
mailing list for people who use SMART (smart-peoplecs.cornell.edu).<BR>
<BR>
<P>
The bad news: the manual. What manual? SMART is not for the faint of
heart; after unpacking and compilation you'll find some extremely
obscure notes and examples and that is it. Nevertheless, if you have
more than just a few megabytes of text to manage AND the stamina to
learn SMART, it certainly is the best solution for your information
retrieval needs. But don't I wish somebody would write a comprehensive
manual! In the meantime you may perhaps be helped by my ``tutorial for
newbees'', to be found at
http://pi0959.kub.nl:2080/Paai/Onderw/Smart/hands.html.<BR> <BR>
<P><HR> <P>
<h3>Bibliography</h3>
<DT><A NAME="BlairMaron1985"><STRONG>1</STRONG></A><DD>
Blair, D.C.; Maron, M.E.,<EM>An evaluation of retrieval effectiveness for a full-text document retrieval system</EM>,Communications of the ACM V28:3, 1985, pp.
289-299.
<P>
<DT><A NAME="SaltonMcGill1983"><STRONG>2</STRONG></A><DD>
G. Salton and M.J. McGill,<EM>Introduction to Modern Information
Retrieval</EM>
New York [etc.] : McGraw-Hill, 1983.
<P> <hr> <P>
<center><H5>Copyright &copy; 1997, Hans Paijmans <BR>
Published in Issue 13 of the Linux Gazette</H5></center>
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<center>
<H2>About Linux text editors / product announcement</H2>
<H4>By Oleg L. Machulskiy
<a href="mailto:machulsk@shade.msu.ru">machulsk@shade.msu.ru</a></H4>
</center>
<P> <HR> <P>
<ul>
<LI><A HREF="#txtunix">Generally about Linux text editors</A>
<LI><A HREF="#myreq">What I'd like to have in text editor</A>
<LI><A HREF="#Cex">Some program examples</A>
</ul>
<P>
<HR>
<P><A NAME="txtunix"></A><B>Generally about UNIX text editors</B> </P>
<P>All of my friends who use Linux always told me that text editors is
very important problem under this OS (I mean text-mode editors with 100K
executable for writing programs).
As I understand, this problem is not a problem of Linux itself,
but it's a problem of every UNIX. What's more I know which reasons cause
this trouble. There is two reasons: <TT>putc</TT> output to screen and
<TT>getc</TT> input from keyboard. In other OS-es user (programmer) can
catch <TT>Alt+&lt;letter&gt;</TT> or <TT>Shift+&lt;letter&gt;</TT> keystrokes
and use it as a commands of editor. In UNIX user has only 256 ASCII-codes
avialable (really, much less than 256) and because of it every UNIX editor
uses either very long sequences of keystrokes as editing commands (as emacs
or joe) or it has two editing modes (command mode and typing mode in VI
for example). On X-s everything is better, because here we can get scan
code (not real scan, but this code is anough for all my needs)
of the key pressed and status of Shift-keys (Alt, Caps, Shift, Ctrl
and mouse buttons), so we can use functional keys, arrow-keys and everything
else You can find on Your keyboard (everybody knows how to do that).
</P>
<P>But even with text mode editors under Linux everything is not so bad:
You can switch keyboard to <A HREF="#Cex">RAW mode</A>
and do with it all You want (don't
forget to get another console from which You will execute <TT>shutdown
-r now</TT> command during beta-testing Your program). But it's very important
to understand that RAW-keyboard programs will not work through telnet.
Also is very important to set <TT>SIGSEGV</TT> and <TT>SIGKILL</TT> signal
handlers so that they'll switch keyboard back to normal mode from RAW when
something happens.
Once I heard about kernel patching so that You can use <TT>ScrollLock</TT>
key to switch between raw and normal mode, but I don't know how to apply
this patch. </P>
<P>
<HR>
<P><A NAME="myreq"></A><B>What I'd like to have in text editor</B> </P>
<P><i>Caution :</i> This section is very private. Maybe someone will find something useful
for him(here) here, but probably not. This section is mostly about my own
text editor, so, if You got used to Turbo-Vision-like editors and You're
satisfied, then probably You will find the follwing not interesting. So
don't read it, don't waste Your time.</P>
<OL>
<B><LI></b>Editor must be the same on every operating system
(multi-platform).
<P><B><LI></B>Editor must handle advanced search feature: I need not only
case sensetive/insensetive search, but as a minimum a wildcard searh or
regular expressions search (this type of search includes wildcards).
<P><B><LI></B>Editor must support projects: user must be able to create
a list of files (sources of some program) and walk through these files
freely (enter into file, quit from file, switch to another file, ...).
The possible solution is to assign some keystroke as an &quot;enter-into-file&quot;
command, and then, when user invokes &quot;enter-into-file&quot;, open
a file with a name similar to the word under cursor (For example, you can
enter in h-file from the text of c-program; just move cursor to the #include
&quot;...&quot; statement and press the &quot;enter-into-file&quot; key).
<P><B><LI></B>Editor must handle many files opened at the same time so
that user can freely move from one text to another (very often I need to
read declarations of functions in <TT>.h</TT> files)
<P><B><LI></B>Editor must support compiling, make etc. from within text
editor (generally: execution OS command from within editor)
<P><B><LI></B>Commands must be rather simultaneous pressings of a few keys
than sequences of keystrokes. It seems to me, it isn't comfortable to type
(F10, 'F', 'O' , <TT>filename</TT>) every time You need to open a new file.
Besides, with such a keyboard layout it's impossible to work fast. This
requirement causes a problem: text editor cannot work through telnet, because
telnet protocol transfers only ASCII-codes, but not scan-codes.
<P><B><LI></B>Text editor must consider a text not as a sequence of chars
but as a sequence of lines, where each line is a sequence of chars. There
is a lot of text editors in which text is a vector (For example ME (MSDOS
MultiEdit) , Turbo Editor (Borland Programming Environments), JOE (linux),
etc.), But I don't know how to work with tables in these editors or how
to set <TT>//</TT> (C++ comment) at the beginning of 10 lines of program
on the screen.
<P><B><LI></B>Editor must support macrocommands as a recordable sequences
of keystrokes.
<P><B><LI></B>If editor supports programming language, so that I can write
my own commands, it would be fine.
<P><B><LI></B>I think programs-structurizing is very useful feature.
I'll explain: I'd like to have text of my program in pre-hypertext
form so that I see a list of functions on the screen, I put cursor
on the name of desired function, press "open"-key and now I can
edit source of that function, but besides that I must be able
to edit this file with usual text editor and I must be able
to compile that file without errors, hence all additional info
about hypertext structure of program must be placed into comments
(comments are specific for each file type, but in most cases
it depends on file extension).
<P><B><LI></B>Keyboard layout must be as much tunable as possible (if
my <TT>End</TT> key is broken, I can use <TT>F11</TT> key instead). Besides
I often need keyboard layout for second language (cyrillic).
<P><B><LI></B>I don't like when editor wastes screen space on frames of
windows or any other unuseful things (80 * 25 isn't very roomy)
<P><B><LI></B>Font on the screen must be fixed (I hate proportional fonts).
</ol>
<P>
If You're interested in all that, You can try our example of such a text editor.
I think it isn't the best editor, but I got used to it. May It will be useful for
someone. To get it, go to
<A HREF="http://shade.msu.ru/~machulsk">http://shade.msu.ru/~machulsk</A>
and download 330K zip file,
which contains sources and 5 executables for
Linux console, Linux X11, OS/2, DOS and Win32 (95/nt).
Docs are also included in HTML / plainTeX format.
<P>
<HR>
<P><A NAME="Cex"></A><B>Example of switching to RAW keyboard mode (C++ syntax)</B> </P>
<pre>
#include &lt stdio.h &gt
#include &lt stdlib.h &gt
#include &lt unistd.h &gt
#include &lt errno.h &gt
#include &lt linux/kd.h &gt
#include &lt signal.h &gt
#include &lt sys/ioctl.h &gt
/*.................*/
void Terminate(int a) {
if( ioctl(con_fd,KDSKBMODE,om)&lt;0 ) {puts(&quot;Press RESET?&quot;);exit(-1);}
/*trying to set old keydoard mode*/
}
/*.................*/
class TKeyboard{
int om; /* old keyboard mode descriptor */
int con_fd; /* console descriptor */
TKeyboard(){
signal(SIGKILL, Terminate ); /*setting SIGKILL signal handler*/
signal(SIGQUIT, Terminate ); /*setting SIGQUIT signal handler*/
signal(SIGSEGV, Terminate ); /*setting SIGSEGV signal handler*/
if( 0==(con_fd=open(&quot;/dev/tty&quot;,O_RDWR)) ) {puts(&quot;error&quot;);exit(-1);}
/*getting console descriptor*/
if( ioctl(con_fd,KDGKBMODE,&amp;om)&lt;0 ) {puts(&quot;error&quot;);exit(-1);}
/*getting old keydoard mode*/
if( ioctl(con_fd,KDSKBMODE,K_RAW)&lt;0 ) {puts(&quot;error&quot;);exit(-1);}
/*setting RAW keydoard mode*/
}
~TKeyboard(){
Terminate(0);
}
int GetScanCode(){
int c;
ioctl(con_fd,TIOCINQ,&amp;cd); /*query*/
if(cd==0) /*keyboard buffer is empty*/
read(con_fd,&amp;c,1); /*get next scancode from console*/
}
} KBD;
/*.................*/
void main() {
/*.................*/
/*................. program body */
/*.................*/
}
</PRE>
<hr>
<p>Thank You!</p>
<ADDRESS> My addresses:
<I><A HREF="mailto:machulsk@shade.msu.ru">machulsk@shade.msu.ru</A></I>
</ADDRESS>
<A HREF="http://shade.msu.ru/~machulsk">homepage on(in?) Shade</A>
<hr>
<p><I>scuze me for bad english, but my native language is Russian
</I></p>
<P> <hr> <P>
<center><H5>Copyright &copy; 1997, Oleg L. Machulskiy<BR>
Published in Issue 13 of the Linux Gazette</H5></center>
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&quot;Linux Gazette...<I>making Linux just a little more fun!</I>
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<center><h1>Two New X-windows Mail Clients</h1></center>
<center><h4><a href="mailto: layers@vax2.rain.gen.mo.us">by Larry
Ayers</a></h4></center>
<center>Copyright (c) 1996</center><BR>
<center><H5>Published in Issue 13 of the Linux Gazette</H5></center>
<hr>
<center><h3>Introduction</h3></center>
<p>There are several full-featured text-mode mail clients available for Linux,
and these programs (such as Pine and Elm) are probably the most commonly used
mailers in the Linux/unix world. One reason for this tendency is that they
run equally well in both console and X sessions (in an xterm). They also have
a longer development history than their X-windows counterparts which results
in the accretion of more features and options. There has been ample time for
the developers to deal with bugs as well.
<p>Many of the X-windows mailers I've tried have either been too basic, too
beta, or awkward to use. I've always returned to Pine, my standby. Recently
two X-based mailers have been released (in late beta versions), both of which
are stable and well-provided with features and options. When I say stable I
mean that they have functioned well for me, I haven't lost any mail, and
they both have been through several releases in which the most egregious
bugs seem to have been ironed out.
<p>Mail programs are a rather personal sort of software. I've found it to be
prudent to copy any existing mailbox files or directories to a safe location
before installing any new mail client. You never know until you try just what
a new mailer will do with your existing mail messages the first time it is
run. As an example, mbox-style mail "folders" (which are just single files
with messages concatenated) might be willy-nilly transformed into MH-style
directories, with each message becoming an individual numbered file. I
suppose there may exist a technique to reverse this metamorphosis, but I don't
know what it might be, aside from manually using an editor.
<hr>
<center><h3>TkMail</h3></center>
<p><a href="mailto: raines@slac.stanford.edu">Paul Raines</a> has been working
on a Tcl/Tk mail client for some time now. I'll let him describe its
origin:<br>
<pre><i>
I began the project at the beginning of '92 while a physics
grad student at the Univ. of Penn. I had been put in charge
of several SGI workstations and was disappointed in the X
window mail readers I had found. I had recently got into
Tcl/Tk programming and played around with putting Tk
interfaces on top of command line programs for physics
simulation. I figured it would be easy to do one to sit on
top of the mailx command and did. That produced tkmail 1.x.
Eventually I decided I was too limited by the mailx command
and wrote a Perl backend to serve as an extensible
equivalent. That produced tkmail 2.x. Perl was used because
its text processing features were much faster than Tcl but I
wanted to keep the whole program as scripts for portability.
This proved a lost cause as Perl proved as hard to port as C
code. For my update to work with Tk4.0, I decided to drop
Perl in favor of writing my own C code as a module extension
to Tcl. The past year was the last of my graduate career and
mostly devoted to finishing my thesis leaving little time
for work on tkmail. It is sort of behind in some of the
features out there today (MIME, POP, IMAP, etc) but I hope
to rectify that soon.
The most important future plans are:
* better MIME support
* better key binding customization
* an "auto-filing" feature
* better search support </i></pre> <br>
<p>TkMail is very customizable; Paul Raines includes with the distribution an
alternate Tk text-manipulation library which allows the use of emacs-style
key-bindings in the compose window. This library can be used with other Tk
programs as well. Colors and fonts can be independently selected for the
folder-view and compose window. Much of the configuration can be done from
menu-selections.
<p>Here is a screenshot of the main folder-view window:<br>
<p><center><a href="./gx/ayers/main.gif">Tkmail Main Window</a></center>
<p>And here is one of the composition window:<br>
<p><center><a href="./gx/ayers/comp.gif">the Composition Window</a></center>
<p>TkMail, like many other Linux mailers, in effect acts as a front-end to
sendmail. Luckily most recent Linux distributions come with sendmail
preconfigured. If your inbox is on a POP server you will need to use
popclient, fetchmail, or fetchpop to retrieve your messages and leave them in
a mailbox file on your local disk, where mail clients can find them.
<p>Among the many features of this beta release are:<br>
<ul>
<li>easy inclusion of files into message compositions with
automatic uuencoding and compression, if desired
<li>ability to access an alternate editor from the composition window
<li>spell check compositions using an X windows interface (using ispell)
<li>reads aliases from either standard .mailrc or elm aliases.txt
<li>sorting of messages on any field and the ability to
write out the folder physically in that order
<li>simple MIME reading and composition tool
<li>built in 'biff' icon for notification of new mail
on multiple folders
<li>dynamic (at startup) menus for quick access to mail folders
for reading, copying, and moving messages
</ul><br>
<p>TkMail is set up initially to open a small debugging window from which the
main program can be started. Once it becomes evident that the program is
working to your satisfaction this can be disabled by editing the main
<b>tkmail4</b> script and changing the line <i>set mfp(debug) 1</i> to <i>set
mfp(debug) 0</i>, or just start it with the <i>-nodebug</i> option.
<p>I have found TkMail 4.0b8 to be easy to learn and use, and its interface is
nice-looking. With a little more work on the MIME abilities it will be as
effective an X mail client as any available.
<p>Paul Raines maintains a
<a href="http://www.slac.stanford.edu/~raines/tkmail.html">home page</a> for
TkMail; the source for the 4.0b8 version is available
<a href="ftp://ftp.slac.stanford.edu/TkMail/BETA/">here</a>.
<hr>
<center><h3>XFMail</h3></center>
<p>Some months ago John Fisk wrote about the XFmail program in the Gazette.
His account inspired me to try it out, but I had quite a few problems with the
message editing window, so much so that when I tried to mail the developers a
comment on their program, the message was corrupted and I doubt that it was
legible to them. I gave up and deleted it soon after, making a mental note
to check it out later when perhaps it had become more usable.
<p>Recently I did just that, and found that a new editing module had been
contributed which really makes a difference in usage of the mailer. No longer
is there a limit to the amount of the text in the editing window. This
change, I believe, makes XFMail a credible choice as a Linux mail client.
<p>XFMail requires the XForms library. This is available from
<a href="http://bragg.phys.uwm.edu/xform">the XForms web-site</a>, which will
always have the latest version and news. If you obtain the archive be aware
that the package includes a GUI designer as well as many samples. All you
need to keep if you're not a programmer is the XForms shared and static
libraries (libforms.so.81 and libforms.a) and the header file (forms.h). These
three files will enable you to compile XForms applications, such as XFMail
from source.
<p>In order to try the current beta (which I recommend) you'll need to obtain
the source archive from the
<a href="ftp://Burka.NetVision.net.il/pub/xfmail/work/">
XFMail home FTP site</a>.
As long as you have the XForms library files installed it should compile for
you, notwithstanding the warning message at the FTP site. If your current
mailbox is in the common mailx format (a single file), you might want to copy
the file (INBOX or whatever) to another location before installing XFMail.
The default behaviour is for XFMail to transform your messages into the
multiple-file MH format; after installation you can disable this and move your
mailbox back. If you already store your mail in the MH manner the program
will load your messages without moving them.
<p>Even though XFMail reads and stores messages in MH format, it doesn't
require that you have the MH system installed.
<p>This mail client can handle all mail fetching and delivery needs for a
single-user machine. The user is given the option of using sendmail for
delivery (either on- or off-line), or using XFMail to directly contact the
SMPT server and deliver outgoing mail. Fetching new mail can be done
externally,(popclient et al), or via XFMail directly. These features could be
helpful for new users who would rather not deal with sendmail; all functions
can be handled by the mailer.
<p>XFMail has the recognizable XForms look, familiar to users of the Lyx
front-end program for TeX/Latex. The XForms library gives programs a unique
look, unlike standard X or Motif. The user interface is perhaps not quite as
fancy as some, but it's not hard to become accustomed to it. There are some
limitations in choice of colors; the selection available is greater than that
of console-ANSI programs, but less than the amount available to standard X
clients.
<p>Here are some screenshots of the various XFMail windows:<br>
<p><center><a href="./gx/ayers/xf_main.gif">The Main Window</a></center><br>
<center><a href="./gx/ayers/xf_comp.gif">The Composition Window</a></center><br>
<p>And here is the logging window:<br>
<p align=center> <img src="./gx/ayers/xf_log.gif"></p><br>
<p>Among the other features of this mailer are an internal address book, full
MIME support, and support for faces and picons. Support is planned for
compatibility with mailx-style mail-folders.
<p>XFMail is quite an ambitious programming project; if you do try out the
beta version I'm sure the authors would appreciate hearing any comments you
may have. There also exists an XFMail mailing list; send a message to:
<a href="mailto:majordomo@Burka.NetVision.net.il">
majordomo@Burka.NetVision.net.il</a>
with "subscribe xfmail" in the message body.
<p>Visit <a href="http://burka.netvision.net.il/xfmail/xfmail.html"
>the XFMail homepage</a> for the latest news; by the time you read this, beta
0.5 may well have been released.
<p>XFMail is being developed by <a href="mailto:gen@NetVision.net.il">
Gennady B. Sorokopud</a> and <a href="mailto:ugen@NetVision.net.il">
Ugen J.S. Antsilevich</a>.
<hr>
<address><a href="http://vax2.rainis.net/~layers/">
Larry Ayers&lt;layers@vax2.rainis.net&gt;</a>
</address>
<!-- hhmts start --> Last modified: Tue Dec 17 19:05:43
CST 1996
<!-- hhmts end -->
<P> <hr> <P>
<center><H5>Copyright &copy; 1997, Larry Ayers <BR>
Published in Issue 13 of the Linux Gazette</H5></center>
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&quot;Linux Gazette...<I>making Linux just a little more fun!</I>
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<!--===================================================================-->
<center><h1>Miscellaneous Notes</h1></center>
<center><h4><a href="mailto: layers@vax2.rainis.net">by Larry
Ayers</a></h4></center>
<center>Copyright (c) 1996</center><BR>
<center><H5>Published in Issue 13 of the Linux Gazette</H5></center>
<hr>
<center><h3>Fun with Little Shell-Scripts</h3></center>
<p>After typing the same command or editing the same rc-file for
the dozenth time the idea of a short executable shell-script
will gradually rise to the surface of my mind. As an example,
last year after much trial-and error I figured out how to start
my S3 X-server in 16-bit mode. This was great, but I found that
there were a few programs which preferred to be run in 8-bit
mode. Typing <i>startx -- -bpp 16</i> and <i>startx -- -bpp 8</i>
began to become tiresome; then it dawned on me that I could
write a shell script for each color-depth which would do the
typing for me. One of them looks like this:<br><pre>
#!/bin/sh
# x16: starts x in 16-bit mode
startx -- -bpp 16
</pre>
<p>Just a simple little script (made executable with
<i>chmod +x x16</i>) but so handy!
<p>Encouraged by this, it occurred to me that changing
window-managers could be done in a similar way. I normally use
fvwm2, but lately I've been fooling around with one of fvwm's
hacked offspring, the Afterstep window-manager. Since I didn't
have Afterstep's configuration quite as usefully customised as
my mainstay fvwm2's, I didn't want to use it the majority of the
time. Rather than editing ~/.xinitrc each time I wanted to
switch to Afterstep, then again to switch back, I copied
~/.xinitrc twice. The first copy is .xinitrc-f and it's just my
normal copy. The second, .xinitrc-a starts Afterstep instead.
The scripts which control this are as follows:<br><pre>
#!/bin/sh
# xa: starts x with afterstep
cp ~/.xinitrc-a ~/.xinitrc ; startx
</pre>
<p>and<br><pre>
#!/bin/sh
# xf: starts x with fvwm2
cp ~/.xinitrc-f ~/.xinitrc ; startx
</pre>
<p>Of course, while in an X-session another window-manager can be
easily started from a menu. I spend a fair amount of time
working in a console session without X running, in which case
the above scripts are useful.
<p>It just occurred to me as I write this that these tasks could
be as easily done using aliases or functions in ~/.bashrc. The
only difference I suppose would be that shell-functions are
memory-resident whereas the scripts aren't.
<p>These examples may seem self-evident or trivial to the
unix-gurus out there, but they were part of the learning process
for me. Perhaps this piece will encourage the beginners out
there to try some similar scripting.
<hr>
<center><h3>Keyboards and RXVT</h3></center>
<p> Here's a discovery I made recently concerning rxvt, the
memory-saving alternative to xterm. I received an email message
recently in response to my article last month concerning S-lang
applications, in which I opinionated about rxvt vs. xterm. The
poster of the message wondered whether there is any way to use
shift-page-up and shift-page-down to scroll the rxvt window,
similar to the way console screens (and xterms) scroll. I had
tried to get this to work without success, and some usenet
messages had led me to believe that without patching the source
rxvt just wouldn't scroll from the keyboard.
<p>Recently I installed the S.u.S.E. distribution, but didn't
install the supplied rxvt package. I recompiled rxvt version
2.19 in this new environment, and to my surprise the
above-mentioned scrolling keys worked! This piqued my
curiosity, so I began prowling through the directory hierarchy
searching for the difference in config files which made this
behaviour possible. I came up with two differences: first,
there was a new entry in the ~/.Xmodmap file. The lines<br><pre>
keycode 64 = Meta_L
keycode 0x6D = Multi_key
</pre>
<p>had been added to the "keycode 22 = BackSpace" line which I had
in my previous installation. Second, the /etc/termcap file was
different than the ones I'd seen before; a new rxvt stanza had
been included which looks like this:<br><pre>
rxvt|rxvt terminal emulator:\
:am:km:mi:ms:xn:xo:\
:co#80:it#8:li#65:\
:AL=\E[%dL:DC=\E[%dP:DL=\E[%dM:DO=\E[%dB:IC=\E[%d@:\
:LE=\E[%dD:RI=\E[%dC:UP=\E[%dA:ae=^O:al=\E[L:as=^N:bl=^G:\
:cd=\E[J:ce=\E[K:cl=\E[H\E[2J:cm=\E[%i%d;%dH:cr=^M:\
:cs=\E[%i%d;%dr:ct=\E[3k:dc=\E[P:dl=\E[M:do=^J:ei=\E[4l:\
:ho=\E[H:ic=\E[@:im=\E[4h:\
:is=\E[r\E[m\E[2J\E[H\E[?7h\E[?1;3;4;6l\E[4l:\
:k1=\E[11~:k2=\E[12~:k3=\E[13~:k4=\E[14~:k5=\E[15~:\
:k6=\E[17~:k7=\E[18~:k8=\E[19~:k9=\E[20~:kI=\E[2~:\
:kN=\E[6~:kP=\E[5~:kb=\177:kd=\EOB:ke=\E[?1l\E>:kh=\E[H:\
:kl=\EOD:kr=\EOC:ks=\E[?1h\E=:ku=\EOA:le=^H:md=\E[1m:\
:me=\E[m:mr=\E[7m:nd=\E[C:rc=\E8:sc=\E7:se=\E[m:sf=^J:\
:so=\E[7m:sr=\EM:ta=^I:te=\E[2J\E[?47l\E8:ti=\E7\E[?47h:\
:ue=\E[m:up=\E[A:us=\E[4m:
</pre>
<p>I have noticed, though, that if I type the command
<i>echo $TERM</i> in an rxvt window the result is <i>xterm-color</i>, so
perhaps the above rxvt termcap entry isn't being used at all.
<p>I'd love to know if anyone else has any luck transplanting
either or both of these two changes into their system. The rxvt
termcap entry can be pasted right into your /etc/termcap file; in
mine it is right after the xterm stanzas. I don't believe the
order of stanzas is important, though.
<hr>
<center><h3>Partitions and Directories</h3></center>
<p>After using linux for a while you tend to take for granted the
supple flexibility inherent in the Linux manner of dealing with
files, partitions, and mount-points. Recently I began to feel
constrained by a relatively small /usr partition, so I thought
I'd do some experimenting.
<p>I happened to have an unused 100 mb. partition on my disk, so
I created an ext-2 filesystem on it and mounted it on an empty
directory, /new, created for this purpose. Then I ran this
command: cp -a /usr/X11R6 /new. Using cp with the -a switch is
really handy, as it copies all subdirectories, links, and files,
and also saves permissions.
<p>The next step was modifying the /etc/fstab file, inserting the
following entry which causes /usr/X11R6 to be mounted on the new
partition:<br><pre>
/dev/hda11 /usr/X11R6 ext2 defaults 1 2
</pre>
<p>Before rebooting I dropped back to a console and deleted the
entire contents of the /usr/X11R6 directory.
<p>I was reasonably certain this would work, but I must confess I
was surprised when (after rebooting) X started up without
comment, as if nothing had changed.
<p>Linux doesn't really care, after all, where files are located,
as long as there is a congruence between the partition table and
the contents of the /etc/fstab file. One benefit of this laxity
is that repartitioning (with all of the attendant backing up,
restoring, etc.) should seldom be necessary.
<hr>
<p><address><a href="http://vax2.rainis.net/~layers/">Larry Ayers&lt;layers@vax2.rainis.net&gt;</a></address>
<!-- hhmts start -->
Last modified: Tue Dec 17 21:31:27 CST 1996
<!-- hhmts end -->
<P> <hr> <P>
<center><H5>Copyright &copy; 1997, Larry Ayers <BR>
Published in Issue 13 of the Linux Gazette</H5></center>
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<H4>
&quot;Linux Gazette...<I>making Linux just a little more fun!</I>
&quot;</H4>
<P> <HR> <P>
<!--===================================================================-->
<center>
<h2>Petition to Cancel Filed Against Linux Trademark</h2>
</center>
<p>Members of the LINUX community have been up in arms during
the past six months over the efforts of an individual named William
R. Della Croce, Jr. from the Boston area to collect 10% royalties on
sales from businesses marketing Linux products. He bases his written
demands on a US trademark which he claims to hold on the name
"LINUX" for a computer operating system. He, in fact, holds such a
registered trademark, based on his claim made under penalty of
perjury that he is the owner and first user of the mark for operating
systems, and that he was not aware in 1994 or 1995 of any other
person who might claim or be using this name and mark for an
operating system. This claim is absurd on its face.
<p>WorkGroup Solutions, Yggdrasil Computing, Linux International,
SSC/<I>Linux Journal</I>, and Linus
Torvalds have retained an internationally known software industry
attorney, G. Gervaise Davis III, of the Davis & Schroeder law firm
in Monterey, CA to seek cancelation of this registration on the
grounds that it is fraudulent and obtained under false pretenses. Mr.
Davis and his firm are handling the case on a vastly reduced fee
basis, because of their long standing relationship with the U.S.
software industry. Davis was the original attorney for Gary Kildall
and Digital Research of CP/M fame in the 1980s.
<p>A Petition to Cancel was in fact filed with the Trademark Trial and
Appeals Board in Washington, DC. on November 27, 1996, detailing the
improper actions of Della Croce and setting out the true facts with
a number of exhibits and attachments. Mr. Davis advises us that we
can expect to have further steps taken by TTAB, under their complex
procedural rules over the next few months. TTAB will first notify
Della Croce of the filing and permit him time to respond, then
evidence can be collected and depositions taken, and then the
parties can file briefs and other responses. Often these cases take
more than a year to be resolved by a TTAB decision.
<p>All of our industry is fully aware that Linus Torvalds developed
Linux and that it has become one of the world's most popular
operating systems during the past six years. The participants in this
proceeding expect the TTAB to cancel the registration, after hearing
and seeing the massive evidence demonstrating that Della Croce had no
conceivable legal basis for his claim to the mark.
<p>The petition itself was available and on
the websites of each of the petitioners and Mr. Davis' law firm at
<a href="http://www.iplawyers.com">http://www.iplawyers.com</a>.
We urge that interested persons read it, and
distribute it and this message to all members of the LINUX community
so that they will be aware of what is being done about this
outrageous trademark claim. We will try to keep everyone posted on
developments in the case through user groups and webpages.
<p>We will continue to keep you updated on the happenings in this action.
Check the Linux Hot News Button for the latest updates.
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<H4>
&quot;Linux Gazette...<I>making Linux just a little more fun!</I>
&quot;</H4>
<P> <HR> <P>
<!--===================================================================-->
<center>
<H2>SLEW: Space Low Early Warning</H2>
<H4>By James T. Dennis
<a href="mailto:jim@starshine.org">jim@starshine.org</a></H4>
</center>
<P> <HR> <P>
<p>One of the worst things you can do to your linux or other
Unix-like system is to allow any of the filesystems to get full.
<p>System performance and stability will suffer noticeable degradation
when you pass about 95% and programs will begin failing and dying
at %100 percent. Processes that are run as 'root' (like sendmail
and syslog) will actually fill their filesystem past 100% since the
kernel will allocate some of the reserved space for them.
<p>(Yes, you read that right -- when you format a file system a
bit of space is reserved for root's exclusive use -- read the
mke2fs, e2fsck, tune2fs for more on that).
<p>Considering the importance of this issue you might think that our
sophisticated distributions would come with a pre-configured way
to warn you long before there was a real problem.
<p>Sadly this is one of those things that is "too easy" to bother
with. Any professional Unix developer, system administrator
or consultant would estimate a total time for writing, installing
and testing such an application at about 15 minutes (I took my
time and spent an hour on it).
<p>Here's the script:
<pre>
#! /bin/bash
## SLEW: Space Low Early Warning
## by James T. Dennis,
## Starshine Technical Services
##
## Warns if any filesystem in df's output
## is over a certain percentage full --
## mails a short report -- listing just
## "full" filesystem.
## Additions can be made to specify
## *which* host is affected for
## admins that manage multiple hosts
adminmail="root"
## who to mail the report to
threshold=${1:?"Specify a numeric argument"}
## a percentage -- *just the digits*
# first catch the output in a variable
fsstat=`/bin/df`
echo "$fsstat" \
| gawk '$5 + 0 > '$threshold' {exit 1}' \
|| echo "$fsstat" \
| { echo -e "\n\n\t Warning: some of your" \
"filesystems are almost full \n\n" ;
gawk '$5 + 0 > '${threshold}' + 0 { print $NF, $5, $4 }' } \
| /bin/mail -s "SLEW Alert" $adminmail
exit
</pre>
That's twelve lines of code and a mess of comments
(counting each of the "continued" lines as a separate line).
<p>Here's my crontab entry:
<pre>
## jtd: antares /etc/crontab
## SLEW: Space Low Early Warning
## Warn me of any filesystems that fill past 90%
30 1 * * * nobody /root/bin/slew 90
</pre>
<p>Note that the only parameter is a 1 to 3 digit percentage.
slew will silently fail (ignore without error) any parameter(s)
that don't "look like" numbers to gawk.
<p>Here's some typical output from the 'df' command:
<pre>
Filesystem 1024-blocks Used Available Capacity Mounted on
/dev/sda5 96136 25684 65488 28% /
/dev/sda6 32695 93 30914 0% /tmp
/dev/sda10 485747 353709 106951 77% /usr
/dev/sda7 48563 39150 6905 85% /var
/dev/sda8 96152 1886 89301 2% /var/log
/dev/sda9 254736 218333 23246 90% /var/spool
/dev/sdb5 510443 229519 254557 47% /usr/local
</pre>
<p>Note that I will be getting a message from slew tomorrow if
my news expire doesn't clean off some space on /var/spool. The
rest of my filesystems are fine.
<p>Obviously you can set the cron job to run more or less often
and at any time you like -- this script takes almost no time
memory or resources.
<p>The message generated can be easily modified -- just
add more "continuation" lines after the 'echo -e' command
like:
<pre>
|| echo "$fsstat" \
| { echo -e "\n\n\t Warning: some of your" \
"filesystems are almost full \n\n" \
"You should add your custom text here.\n"\
"Don't forget to move the ';' semicolon "\
"and don't put whitespace\n" \
"after the backslash at the ends of these lines\n\n";
</pre>
Note how the first echo feeds into the grouping (enclosed by the
braces) so that the contents of $fsstat are appended after the message.
This is a trick that might not work under other shells.
<p>Also, if you plan on writing similar shell scripts, note that the double
quotes around the variable names (like "$fsstat") preserve the linefeeds in
their values. If you leave the quotes out your text will look ugly.
<p>The obvious limitation to this script is that you can only specify one
threshold value for all of the file systems. While it would be possible
(and probably quite easy) to do this some other way -- it doesn't matter to
90% of us. I suspect that almost anyone who does install this script will set
the threshold to 85, 90 or 95 and forget about it.
<p>One could also extend this script to do some groping (using various
complex find commands) to list things like:
<ul>
<li> Who is the biggest disk hog (which user is taking up all the space
and what are his or her largest files)?
<p>
<li> What are the oldest, least accessed files on that filesystem?
<p> This last question could be answered using something like
<pre>
'find -xdev -printf "%A@" | sort -n | head' --
</pre>
which reads something like "find all the links on this filesystem
and print time that they were last access (expressed as seconds
since 1970) and their filenames; sort that and just give me a
few of the ones from the top of the sorted list." As you can
see, find commands can get very complex very quickly.
</ul>
<p>I chose to keep this script very simple and will develope specific scripts
to suggest file migrations and deletions as needed.
<p>As you can see it is possible to do quite a bit in Linux/Unix using
high level tools and very terse commands. Certainly the hardest part
of writing a script like this is figuring out minor details about quoting
and syntax (when to enclose blocks in braces or parentheses) and in
determining how to massage the text that's flowing through your pipes.
<p>The first time I wrote slew was while standing in a bookstore a couple of
years ago. A woman near me was perusing Unix books in my favorite section
of the store and I asked if I could help her find something in particular.
She described the problem as it was presented to her in a job interview.
I suggested a 'df | grep && df | mail' type of approach and later, at
home, fleshed it in and got it working.
<p>Over the years I lost the original (which was a one-liner) and eventually
had one of the systems I was working with hiccup. That made me re-write
this. I've left it on all of my systems ever since.
<p>I'd like to encourage anyone who developes or maintains a distribution
(Linux, FreeBSD, or whatever) to add this or something like it to the
default configuration on your systems. Naturally it is free for any use
(it's too trivial to copyright in my personal opinion; so, that there is
no doubt, I hereby place SLEW (comments and code) into the public domain).
<P> <hr> <P>
<center><H5>Copyright &copy; 1997, James T. Dennis, Starshine Technical
Services<BR>
Published in Issue 13 of the Linux Gazette</H5></center>
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<H1><IMG SRC="../gx/backpage.gif" alt="Linux Gazette Back Page"></H1>
<H5>Copyright &copy; 1997 Specialized Systems Consultants, Inc.<br>
For information regarding copying and distribution of this material see the
<A HREF="../copying.html">Copying License</A>.</H5>
</center>
<P> <hr> <P>
<H3>Contents:</H3>
<ul>
<li><a HREF="./lg_backpage13.html#authors">About This Month's Authors</a>
<li><a HREF="./lg_backpage13.html#notlinux">Not Linux</a>
</ul>
<a name="authors"><p></a>
<P> <HR> <P>
<!--======================================================================-->
<center><H3> About This Month's Authors </H3></center>
<P> <HR> <P>
<!--======================================================================-->
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Larry Ayers</H4>
Larry Ayers lives on a small farm
in northern Missouri, where he is currently engaged in building a
timber-frame house for his family. He operates a portable band-saw mill,
does general woodworking, plays the fiddle and searches for rare
prairie plants, as well as growing shiitake mushrooms. He is also
struggling with configuring a Usenet news server for his local ISP.
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">James T. Dennis</H4>
Jim Dennis
is the proprietor of <A href="http://www.starshine.org">
Starshine Technical Services</A>.
His professional experience includes work in the technical
support, quality assurance, and information services (MIS)
departments of software companies like
<A href="http://www.quarterdeck.com"> Quarterdeck</A>,
<A href="http://www.symantec.com"> Symantec/
Peter Norton Group</A>, and
<A href="http://www.mcafee.com"> McAfee Associates</A> -- as well as
positions (field service rep) with smaller VAR's.
He's been using Linux since version 0.99p10 and is an active
participant on an ever-changing list of mailing lists and
newsgroups. He's just started collaborating on the 2nd Edition
for a book on Unix systems administration.
Jim is an avid science fiction fan -- and recently got
married at the World Science Fiction Convention in Anaheim.
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Bill Duncan</H4>
Bill has worked with Unix systems since the early Version 7 days on PDP-11's.
He worked with Xenix throughout most of the eighties and has also worked
with many other flavors of Unix over the years, but his operating system
of choice is now Linux. When not working or fiddling with his four Linux
systems at home (which is rare), he might have some time left over for his
other hobbies; his dog (Daisy), photography and Amateur Radio.
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Michael J. Hammel</H4>
Michael J. Hammel,
is a transient software engineer with a background in
everything from data communications to GUI development to Interactive Cable
systems--all based in Unix. His interests outside of computers
include 5K/10K races, skiing, Thai food and gardening. He suggests if you
have any serious interest in finding out more about him, you visit his home
pages at http://www.csn.net/~mjhammel. You'll find out more
there than you really wanted to know.
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Oleg Machulski</H4>
Oleg Machulski is a student of
<A HREF="http://mech.math.msu.su/chislmet.htm"> Laboratory
of Computing methods</A>
at the
<A HREF="http://mech.math.msu.su/">Faculty of Mechanics and
Mathematics</A>,
<A HREF="http://www.msu.ru/">Moscow State University</A>.
He has been a Linux enthusiast since Sept.1996 as well as an OS/2 enthusiast.
After receiving the source of a
very unusual DOS text editor, where the program was structurized
in a hypertext manner from his scientific advisor Andrey V. Astreling,
he wrote and ported the following functions:
search, macrocommands, multiple pages and so on.
Brief history of that freeware project could be found at
http://shade.msu.ru/~machulsk/mmm/mmm.html
Also, I like to play guitar and listen to jazz music.
Additional info can be found at my homepage
http://shade.msu.ru/~machulsk
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">
Hans Paijmans</a></H4>
<P>
Hans &quot;Paai&quot; Paijmans is University lecturer &
researcher at Tilburg University and a regular contributor to several
Dutch journals. Together with E. Maryniak he wrote the first dutch
book on Linux--already two years ago. My, doesn't the time fly.
His homepage is at http://pi0959.kub.nl:2080/paai.html.
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Greg Roelofs</a></H4>
Greg Roelofs, aka Cave Newt,
is best described as a phenomenon, as in, ``Captain, we're picking
up strange readings from that unexplained phenomenon over there.''
Greg's job description is appropriately schizoid, given his interest in far
too many things for his own good.
He's a full-time researcher in multimedia/image-compression/WWW stuff
at Philips Research at
Palo Alto, having made the switch from Unix system administrator in August
1995. He likes to fancy himself a
software developer; among other things, he has
been a member of the <A HREF="http://www.cdrom.com/pub/infozip/">Info-ZIP</A>
team for six years and the principal author of
<A HREF="http://www.cdrom.com/pub/infozip/UnZip.html"><B>UnZip</B></A> for
most of that time. (He's also a member of the <B>Portable Network Graphics</B>
Development Group and the maintainer of the
<A HREF="http://quest.jpl.nasa.gov/PNG/">PNG</A> and
<A HREF="http://quest.jpl.nasa.gov/zlib/">zlib</A> home pages.)
As for recreational interests, he likes to amuse himself by cycling
(often to work); skiing--any flavor, although snow preferred, especially
if it means he can drive in it; scuba diving--for 18 years now, from the
shores of Lake Superior to the coast of Venezuela to the kelp beds of
Monterey; and hiking/backpacking, particularly in the Sierra Nevada range;
and amateur photographer.
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">
James Shelburne</a></H4>
<P>
James Shelburne currently lives in Waco, Texas where he spends most of
his free time working on various Linux networking projects. Some of his
interests include Perl + CGI, Russian, herbal medicine and the Ramones
(yes, you heard right, the Ramones). He is also a staunch Linux advocate
and tries to convert every MacOS/MS Windows/AMIGA user he comes into
contact with. Needless to say, only other Linux users can stand him.
<a name="notlinux"><p></a>
<P> <hr> <P>
<!--====================================================================-->
<center><H3> Not Linux </H3></center>
<P> <HR> <P>
<!--======================================================================-->
<P>
Thanks to all our authors, not just the ones above, but also those who wrote
giving us their tips and tricks and making suggestions. Thanks also to our
new mirror sites.
<P>
<img src="./gx/snow.gif" alt="" align=right>
I'd like to apologize for being later than usual getting
<i>LG</i> posted. The weather in Seattle has been a more than a little bizarre
lately. My
neighborhood got about 20 inches of snow from December 26 to December 29.
Since the normal yearly snowfall is about 4 inches, everything stopped,
including the buses for the first time in Metro history. SSC had a portion
of the roof give way under the weight of snow and water (the rains started
December 29 and haven't quit yet). As a result of the flooding, things are
in quite a mess around the office. Yearly rainfall in Seattle is usually 31
inches; this year we had 55 inches. I thought I was back in Houston!
<P>
Actually, I was back in Houston during my vacation week before Christmas.
The weather wasn't
great there either -- rainy and cold, and I was counting on sunshine. However,
I still had a good time visiting with family and friends. My grandchildren, Sarah
and Rebecca, are a delight to be with -- I miss them a lot.
<P>
Have fun!
<P> <hr> <P>
<A HREF="http://www.ssc.com/ssc/Employees/Margie/margie.html">
Marjorie L. Richardson</a><br>
Editor, <i>Linux Gazette</i> <A HREF="mailto:gazette@ssc.com">gazette@ssc.com</a>
<P> <HR> <P>
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