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<center><H2><IMG SRC="../gx/newlogo.jpg"
ALT="Linux Gazette... making Linux just a little more fun!">
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<H5>Copyright &copy; 1996-98 Specialized Systems Consultants, Inc.</H5>
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<H1>Welcome to Linux Gazette!<img src="../gx/tm.gif" alt="(tm)"></H1>
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<H1>Published by:</H1>
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<H1>Sponsored by:</H1>
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Our sponsors make financial contributions toward the costs of
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<I>Linux Gazette</I> is a non-commercial, freely available publication and will
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<!--=================================================================-->
<H1 align="center">Table of Contents <BR>March 1998 Issue #26</H1>
<P> <HR> <P>
<table><tr>
<td rowspan=4>
<UL>
<LI><A HREF="../index.html">The Front Page</A>
<LI><A HREF="./lg_mail26.html">The MailBag</A>
<ul>
<li><a HREF="./lg_mail26.html#ideas">Article Ideas</a>
<li><a HREF="./lg_mail26.html#help">Help Wanted</a>
<li><a HREF="./lg_mail26.html#gen">General Mail</a>
</ul>
<LI><A HREF="./lg_tips26.html">More 2 Cent Tips</A>
<ul>
<li><a HREF="./lg_tips26.html#apache">Apache SSL extensions...</a>
<li><a HREF="./lg_tips26.html#locate">Locate</a>
<li><a HREF="./lg_tips26.html#print">Re: Printing Problems</a>
<li><a HREF="./lg_tips26.html#net">Re: LG25, Netscape on the Desktop</a>
<li><a HREF="./lg_tips26.html#vax">Re: Linux and VAX 3400 and 3300</a>
<li><a HREF="./lg_tips26.html#binary">Binary File Access with dd</a>
<li><a HREF="./lg_tips26.html#find">Follow up to find 2c-tip</a>
<li><a HREF="./lg_tips26.html#ispell">ispell & Pine 3.96</a>
<li><a HREF="./lg_tips26.html#xvscan">XVSCAN: Combining different parts
together </A>
<li><a HREF="./lg_tips26.html#scape">2c-tip: Netscape on the Desktop</A>
<li><a HREF="./lg_tips26.html#win">Linux and Win95</A>
<li><a HREF="./lg_tips26.html#su">My $0.02 tip: Graphical su</A>
<li><a HREF="./lg_tips26.html#eggs">Easter Eggs in Netscape</A>
<li><a HREF="./lg_tips26.html#core">Core Dumps</A>
</ul>
<LI><A HREF="./lg_bytes26.html">News Bytes</A>
<ul>
<li><a HREF="./lg_bytes26.html#general">News in General</a>
<li><a HREF="./lg_bytes26.html#software">Software Announcements</a>
</ul>
<LI><A HREF="./lg_answer26.html">The Answer Guy</A>, by James T. Dennis
<ul>
<li><a HREF="./lg_answer26.html#telnet">Can't Telnet to Red Hat 5.0 Server</a>
<li><a HREF="./lg_answer26.html#luke">Use the Source, Luke!</a>
<li><a HREF="./lg_answer26.html#ifconfig">'ifconfig' to Troubleshoot Dropped Ethernet Packets?</a>
<li><a HREF="./lg_answer26.html#angel">Cthugha </a>
<li><a HREF="./lg_answer26.html#login">xdm Login doesn't!</a>
</ul>
<LI><A HREF="./clueless.html">Clueless At The Prompt</a>, by Mike List
<LI><A HREF="./marsden.html">EMACSulation</a>, by Eric Marsden
<LI><A HREF="./gm.html">Graphics Muse</A>, by Michael J. Hammel
<LI><A HREF="./kapok/kapok-nonote.html">Linux on a Kapok 7200</A>, by Alessandro Usseglio
Viretta
<LI><A HREF="./dubs.html">Low Cost Macintosh-Linux Networking at Home</A>,
by Dr. Richard L. Dubs
<LI>New Release Reviews, by Larry Ayers
<ul>
<LI><A HREF="./ayers.html">Tcd and Gtcd</a>
</ul>
<LI><A HREF="./kunz.html">Setting up Your In-Home (or In-Office)
Network</A>, by Tom Kunz
<LI><A HREF="./obrien.html">The Yorick Programming Language</a>, by Cary
O'Brien
<LI><A HREF="./lg_backpage26.html">The Back Page</A>
<ul>
<li><a HREF="./lg_backpage26.html#authors">About This Month's Authors</a>
<li><a HREF="./lg_backpage26.html#notlinux">Not Linux</a>
</UL>
</UL>
</td>
</tr>
<tr>
<td align=center>
<A HREF="lg_bytes26.html#linuxexpo">
<img src="../gx/linuxexpo.gif" border=0 alt="">
</a>
</td>
</tr>
<tr>
<td align=center>
<A HREF="lg_answer26.html">
<img src="../gx/wizard2.gif" border=0 alt="">
</a>
<A HREF="lg_answer26.html"><i>The Answer Guy</i></a>
</td>
</tr>
<tr>
<td align=center>
<A HREF="./gm.html">
<IMG SRC="../gx/hammel/banner-3.gif" border=0 alt="">
</a>
</td>
</tr><tr>
<td align=center>
<img src="../gx/fisk/attndant.gif" border=0 alt=""><BR>
<!-- <A HREF="wkndmech.html"><I>The Weekend Mechanic</I></a>a -->
<I>The Weekend Mechanic</I> will return.
</td>
</tr><tr>
</table>
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<!--=============================================================-->
<A HREF="./issue26.txt">TWDT 1 (text)</A><BR>
<A HREF="./issue26.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>,
<A HREF="mailto: gazette@ssc.com"> gazette@ssc.com</A>
<H4>"Linux Gazette...<I>making Linux just a little more fun!</I>"</H4>
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<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_mail26.html#help">Help Wanted -- Article Ideas</a>
<li><a HREF="./lg_mail26.html#gen">General Mail</a>
</ul>
</td></tr></table>
</center>
<a name="help"></a>
<p><hr><p>
<!-- =================================================================== -->
<center><H3> Help Wanted -- Article Ideas </H3></center>
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Sun, 01 Feb 1998 21:43:23 -0800<BR>
From: Bradley Akey, <A HREF="mailto:bakey@slip.net">bakey@slip.net</A><BR>
Subject: <B>Creative Labs SB-16 & Sony CDU76E-S</B>
<P>
I am attempting to install RedHAt Linux ver 4.2 from a Sony
CDU-76E-S CD-ROm connected to a Sound Blaster 16 via an IDE interface
at base io 0x1E8, IRQ 15. Waht is the correct boot parameter to get this
CD-ROM to function properley
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Tue, 3 Feb 1998 08:25:32 -0500 (EST)<BR>
From: Michael Stutz, <A HREF="mailto:stutz@dsl.org">stutz@dsl.org</A><BR>
Subject: <B>Help Wanted: recording audio data</B>
<P>
Is there any way to read and save the data that is currently being played by
the soundcard, regardless of the sound source?
<P>
(There is a program in alpha which does this called paudio, at
<A HREF="http://web.syr.edu/~jdimpson/proj/">
http://web.syr.edu/~jdimpson/proj/</A>. It creates a readable /proc/audio --
but I haven't yet gotten it to work with the OSS-compatible driver produced
by the Linux Ultrasound Project which I use.)
<P>
Michael Stutz
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Mon, 09 Feb 1998 14:18:49 -0500<BR>
From: Todd Blake, <A HREF="mailto:tbb@enterprise.aacc.cc.md.us">
tbb@enterprise.aacc.cc.md.us</A> <BR>
Subject: <B>Help Wanted</B>
<P>
I like most people am the only person to use my linux system at home.
What I'd like to do is when my system is done booting to have me
automatically login as my main user account(not as root though) on one
virtual console(the first) and leave all other consoles and virtual
consoles alone, so that someone telnetting in will get a login prompt
like normal, just that I won't. I'd still like the other vc's have
login's for others to login and other reasons. I've tried just putting
/bin/sh in /etc/inittab and that didn't work, and I'm stumped. Does
anyone have any ideas on this?
<P>
Todd Blake
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Mon, 09 Feb 1998 17:47:08 -0600<BR>
From: peter smith, <A HREF="mailto:psmith@computek.net">
psmith@computek.net</A><BR>
Subject: <B>Problems with Linux through Wingate Socks</B>
<P>
I'm having a few problems accessing the internet through Wingate
v2.0 on my Windows95 machine using my Linux Redhat 4.2 installation.
I've had this SOCKS server set-up for quite some time on my internet
dial-out machine and have previously had no problems accessing the
internet through this server via my second machine's installation of
Windows95 or even WindowsNT. The problem is directly related to DNS
lookups. If I access a domain-name from my Linux machine that seems to
get redirected, I will receive an error that the DNS address does not
exist. For instance, if I attempt to open the web page
http://www.kernel.org (which gets redirected to http://linux.kernel.org)
my browser (Netscape v4.04 for Linux 2.0* i386 rpm) reports a DNS
error. However if I instead attempt to open the redirected web page
http://linux.kernel.org my browser will open it ok, without error. I'm
baffled by this behavior and have tried a number of different things! I
can provide more detailed information if needed. Thanks in advance to
any who try to help! ;)
<P>
I love Linux Gazette and have a great time browsing all the cool
suggestions and tips! Keep up the ideas and info!
<P>
PeterS
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Mon, 09 Feb 1998 19:04:42 -0500<BR>
From: Melmac88, <A HREF="mailto:smegan@erols.com">smegan@erols.com</A><BR>
Subject: Shadow passwords
<P>
Can someone do a clear explanation on how to set up a shadow
password file, and exactly how it works? I've seen this
recommended for security purposes in many books and
articles, but there never seems to be an explanation on how
to do this.
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Wed, 09 Dec 1998 04:38:06 -0900<BR>
From: David Lev, <A
HREF="mailto:dlev@polarnet.com">dlev@polarnet.com</A><BR>
Subject: <B>my dual pentium</B>
<P>
My name is David Lev, I have a problem with my
second CPU.
<P>
I am currently using a Caldera OpenLinux Standard
with Kernel (2.0.29-2).
After I install the system I try to enable the 2
CPU and my computer FREEZE or I loss my DeskTop
and it takes for ever to do one process.
but with one CPU the computer work fine no
problems at all.
I ask for your help.
If you can help me also on how to enable 2 modems
and run them as one.
<P>
My computer content:
<PRE>
ATX Dual Motherboard - GA-586DX with SCSI on board
Adaptec 7880
CPU - 2x 233MMX Pentium
128M RAM EDO
2x 3.1G HDD - W.D - IDE
2x 8X CD-ROM - IDE
2x 56K Modem
ESS Sound card
</PRE>
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Sat, 14 Feb 1998 15:00:34 EST<BR>
From: Andreas M. Weiner, <A HREF="mailto:HGuAWeiner@aol.com">
HGuAWeiner@aol.com</A> <BR>
Subject: <B>Linux and AMD K6 Processor - any Problems?</B>
<P>
This is my hardware configuration.
Support answered that there would be problems with using the K6 with Linux; for
instance a crash.
<P>
What dou you know about this problem ?<BR>
Could you send me a some informations to solve this problem ?<BR>
Are there Kernel patches available ?<BR>
<P>
I'm looking forward of getting the answers from you
<P>
Andreas M. Weiner
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Sun, 15 Feb 1998 10:26:36 -0800<BR>
From: David, <A HREF="mailto:elvii@writeme.com">elvii@writeme.com</A><BR>
Subject: <B>X without a Mouse?</B>
<P>
Been searching around the net and ldp, and can't seem to find anything
on this one. Trying to be able to use X WITHOUT a mouse. Yes, I know,
it works bets with a mouse, but I'd like to be able to get at least
limited x funcationality without it. Any help is greatly appreciated,
and being waited. Also, is there any was to do mouse emulation without
a mouse? I found a program that translated ps/2 to a standard serial
mouse, for before x supported ps/2, i assume... anyone know if a
program has been written to allow the keypad to do mouse, ie, translate
keypad input to /dev/mouse? Thanks for your time, hoping some kind
linux guru's out there can help. :)
<P>
David
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Mon, 16 Feb 1998 21:59:04 -0700<BR>
From: Todd Jamison, <A HREF="mailto:jamisont@littoneos.com">
jamisont@littoneos.com</A><BR>
Subject: <B>Help with Sound Card</B>
<P>
I currently am running RedHat 5.0 on a Pentium 150 W/48 MB Ram. I =
cannot get my ESS ES1868 plug and play sound card to work. I am very =
new to linux and am still learning. If anyone can help me i would =
really appreciate it.
<P>
Todd
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Tue, 17 Feb 1998 16:41:49 -0600<BR>
From: John Gorman, <A HREF="mailto:John.H.Gorman@MCI.Com">
John.H.Gorman@MCI.Com</A><BR>
Subject: <B>HP4 & font</B>
<P>
I just installed a HP LaserJet 4L on RedHat 4.2 Intel and when I
print postscript (from emacs, etc), it prints at about a size 24
font. How to I set my font where I want it.
<P>
Thanks
<P>
John Gorman
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Fri, 20 Feb 1998 08:46:12 +0100<BR>
From: Jeroen Bulters, <A HREF="mailto:jbulters@scoutnet.nl">
jbulters@scoutnet.nl</A> <BR>
Subject: <B>Changing XDM windows</B>
<P>
Can I change the XDM login window/screen?
I have a cool house logo so i want to use it in my own Home Network. And at
my school they want to know to so. Is it possible.
If yes, how? If no, WHY NOT.
<P>
Jeroen Bulters, The netherlands
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Tue, 17 Feb 1998 01:36:30 +0000<BR>
From: Mackenzie St. Louis, <A HREF="mailto:mstlouis@tiac.net">
mstlouis@tiac.net</A> <BR>
Subject: <B>New Motherboards</B>
<P>
A lot of motherboards have been coming out lately with built in
graphics and sound. Any plans to cover them. I just bought a
TX-Pro-II board with graphics and sound. However I think I will be
returning it since I can't get the sound to work. It has a SoundPro
chip. Can not also get XFree 3.3.1 to run properly. It will only come
in 8 bit 320x200, even though the graphic chip is supposed to be AGP.
If you could point out where I can get some info. I would gladly write
an article for the Gazette in case any else comes across this same
problem. Please email me with any info or questions.
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
<a name="gen"></a>
Date: Tue, 24 Feb 1998 16:28:09 -0800<BR>
From: chewey nougat, <A HREF="mailto:daiger@usc.edu">
daiger@usc.edu</A> <BR>
Subject: <B>HELP-Installing Linux on a FAT32 Drive</B>
<P>
I'm interested in installing linux on a machine I built recently, but =
when I installed Win95(b), I idiotically opted to format the drive using =
FAT32, which in a 95-only environment is great, but linux can't read it =
for greek.
<P>
I've looked around for utilities to effectively un-FAT32 the drive, =
which I will then partition with Partition Magic to use the freespace as =
a native ext2 partition, etc., but am having little luck. Reformating is =
a disheartening prospect I would rather not face, but am fully prepared =
to do so if I don't find any help here.
<P>
much thanks,<BR>
nate daiger
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Thu, 26 Feb 1998 13:47:06 -0500<BR>
From: Brian O. Bush, <A HREF="mailto:bbush@xtdl.com">
bbush@xtdl.com</A><BR>
Subject: <B>question on motor control</B>
<P>
Does anyone know how to interface and control two motors from a Linux box?
I am looking for a simple solution (in circuit at least).
<P>
Thanks,<BR>
Brian
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Fri, 27 Feb 98 14:16:13 -0500<BR>
From: Bill R. Williams, <A HREF="mailto:brw@ETSU.Edu">
brw@ETSU.Edu</A><BR>
Subject: <B>Wanting HELP!</B>
<P>
First off: I can *not* believe I am the only one bitten by this.
<P>
In the process of getting a System installed I upgraded from the
original CD-ROM install of (Intel) RedHat 4.2 to the new RedHat 5.0
CD-ROM. One of the significant items on this system is the mars-nwe
Netware emulator.
<P>
Under the RedHat 4.2 with mars-nwe 0.98pl8-1 the mars package ran fine,
but logged copious errors about there being "too many connections --
increase the number in config.h". But it ran, and I *liked* the way it
happily did Netware duties! (Especially the printer part.)
<P>
The *new* RedHat 5.0 with mars-nwe 0.99pl2-1 offered some very desirable
abilities, not the least of which is the move of some items (such as
number of connections) to the run-time config file (/etc/nwserv.conf
under RedHat, probably nw.ini on other distributions.) Now the bad
news...
<P>
Of lesser, but still irritating, importance is the fact that the mars
package won't shutdown without some hard kills. This may be related to
the really important problem which is:
<P>
This new package spawns out nwconn processes with an empty parenthesis
as the last token instead of the USERID ('nwconn ... ()') until all
connection slots are eaten, and then, of course, will not recognize any
new attempts. Any users already logged into the nwserv(ice) are Ok.
<P>
Since I am neither a Netware guru nor a mars guru I can only hazard a
guess, but since the nwconn(s) are children of the ncpserv daemon I
suspect that ncpserv is the source of the troubles.
<P>
I have tried every combination of parameter twiddling in the run-time
config file that can think of, but to no avail.
<P>
One thing I have noticed, the 2.0.32 linux kernel /usr/src/linux/.config
no longer has the 'CONFIG_IPX_INTERN' setting (should be unset according
to mars-nwe docs) which existed in 2.0.27. This may or may not have
anything to do with the problem. Checking the kernel sources, it
appears that the RedHat rpm of the 2.0.32 kernel has the mars patches
incorporated into the source.
<P>
Anyone who has solved this problem, please share the secret.
<P>
BTW: I attempted resolution through the RedHat Support system as a
registered RedHat customer, and if anybody wants a good laugh I'll be
happy to share the "circle of correspondence" from RedHat support. I
did learn from the attempt that no *human* at RedHat actually ever sees
the E-Mail to the support team or 'Bugs' team. (The "auto answer"
mechanism will get right back to you, though, and tell you not to expect
an answer.)
<P>
As I said, I can *not* believe I am the only one bitten by this, because
I've looked on the news groups and seen several posts with "Mars and
RedHat 5.0" in the Subject fields. These were all on the French
os.linux.... lists, and unfortunately I do not read French!
<P>
Sorry for the rambling on...<BR>
Bill R. Williams
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Sat, 7 Feb 1998 13:03:24 +0100 (CET)<BR>
From: Manfred Lemke, <A HREF="mailto:lema0019@FH-Karlsruhe.DE">
lema0019@FH-Karlsruhe.DE</A> <BR>
Subject: <B>Support for IBM Ethernet card?</B>
<P>
I'm frantically searching for some kind of support for IBM's
LAN Adapter/A for Ethernet. Does any of you know of a driver
in the Linux Kernel that works?
<P>
Best regards and thanks in advance,
<P>
Manfred Lemke
<P> <hr> <P>
<!-- =================================================================== -->
<center><H3> General Mail </H3></center>
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Fri, 27 Feb 1998 00:09:33 +0100 (MET)<BR>
From: Radoslav Dejanovic, <A HREF="mailto:rdejanov@public.srce.hr">
rdejanov@public.srce.</A><BR>
Subject: <B>Linux Journalists International</B>
<P>
Linux Journalists International is an effort to make a meeting point
for journalists who use Linux or simply write about it. It is also a place
where other journalists and other people can take a look what is going on
with Linux and media that supports it. There will be info pages about
magazines/media and journalists who use Linux and/or write about Linux &
related software.
<P>
I am editor in one croatian computer magazine (http://www.pcchip.hr) and
this is my effort to give the Linux community something that lacks:
popularity in media and a chance to boost media coverage of Linux.
The homepage is at http://www.purger.com/~rado/lji.html - please take a
look at it. LJ and LG are the strongest "Linux inside" media :), so your
support in this project is essential.
<P>
Rado
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Wed, 4 Feb 1998 10:02:08 -0500 (EST)<BR>
From: Paul Lussier, <A HREF="mailto:plussier@LanCity.COM">
plussier@LanCity.COM</A> <BR>
Subject: <B>Retraction Re: Linux and routing</B>
<p>
It was just called to my attention that this came across a little to
strongly and I'd like to clarify what I had previously written.
<p>
On Tue, 6 Jan 1998, I wrote:
<blockquote> <I>
Some words of caution. DO NOT HAVE YOUR LAN CONNECTED AT THE TIME OF
THE CABLE MODEM INSTALLATION!!!! [Comapany names removed],
and most of the other cable companies (we deal with them all here)
will refuse to connect a LAN to their broadband network. Simply
remove your hub or coax cable from view, and let them do what they
need to do, then connect everything else up after they leave.
</I> </blockquote>
<p>
This was probably a little of an overstatement. I know only of 1 company
that has this as a policy, but have heard of people having problems with
some of the others. I have even recently been informed of one company
that is *quite* Linux friendly and will "encourage the use of Linux as
firewall/routers" as well as "allow and assist individuals & companies to
setup there own Web servers, either at their permises or ours. We offer
web hosting and will assist in registering a domain name". So, I
obviously made an improper, blanket statement which does not represent the
attitudes or policies of all companies.
<blockquote> <I>
Some other interesting tidbits of information about cable modems and
cable companies:<BR>
1. Do not expect support for running a LAN over the cable modem
from the cable company. They don't want you to do it, they
won't help you do it.<BR>
2. Do not expect to put up a web server to be accessed by from
the internet. You are a client, not a server. This
technology,though fully capable of performing in this
manner, is not being deployed for use this way.
</I> </blockquote> <P>
Again, this is a blanket statement that *does not* apply to all cable
companies. There is a good reason for those companies who do hold this
policy, and perhaps I should have gone into more detail. When you get a
cable modem from a cable company, *typically* you are agreeing to lease
the equipment from them under similar agreement as you rent the TV set top
box for cable television reception. The agreement typically states that
you are not allowed to run the cable to any other TV for which you do not
rent a box. The same goes for the cable modems. They are agreeing to
lease you 1 modem for 1 computer. Setting up a firewall/proxy server to
enable other systems access is exactly like placing a diplexor on you TV
set, and running the cable to another television. That is a violation of
the agreement, and is illegal, immoral, and unethical; it's stealing. And
again, I re-iterate, this is not true for *all* companies. Check with
your cable company, they should be happy to explain their policies to you.
<p>
I don't really think you *should* expect to be able to do either of these
though, unless the cable company has provisions in place. You are
agreeing to connect one computer to their network as a client. Anything
more, you should expect to pay more, as they are providing you with
increased capabilities. Just like the phone company charges more per
added service (*69, caller ID, etc) so should the cable companies.
Personally, I think that average rate of US$40-$50 a month for the
equivalent of a T1 to my house is an awesome deal. If I want more
capability, I should expect and be willing to pay more.
<blockquote> <I>
Cable companies WILL shut you down for running a server of
anykind on your end of the network, and it can be *forever* :(
</I> </blockquote> <P>
Again, I spoke without clarification. Obviously it depends upon the
policies of your local cable company. I know of 2 or 3 instances where
this has been the case. By stating the above, I was trying to warn of the
possible consequences of violating the contract with the cable company.
If the cable company specifies in the contract what you are allowed to do
and what you are not allowed to do, you should expect to deal
with the consequences of violating the agreement.
<blockquote> <I>
Spammers love cable/broadband networks. There have been
several cases where a broadband network customer has been
used by spammers and were subsequently shutdown for life by
the cable company. What happens is the person decides to
connect their private LAN to the cable modem but sets the
firewall up incorrectly. Spammers search cable/broadband
networks for proxy servers/firewalls (Usually Win95/NT) that
allow incoming connections and then use that system to spam
the entire cable/broadband network making the spam appear as
if you sent it.
</I> </blockquote> <P>
Spammers love any insecure system or network. Broadband Technology
though, for the first time has allowed people more extensive and
closer contact with other people on the internet. When you dial into an
ISP with a normal modem, it's a little more difficult for devious minded
people to take advantage of other users. But with cable modems, you now
have hundreds and/or thousands of people all on the same private network,
all with similars IP addresses, many of whom, now leave their systems
connected for much longer periods of time. This makes it much easier for
crackers, and other mischievous people, to take advantage of anyone who
isn't running a properly secured system.
<blockquote> <I>
Usually you will be given 1 warning by the
cable company, but there have been cases where none was
given and the customer was completely shut down.
</I> </blockquote>
I have heard of this happening on several occasions, where usually the
person was running an improperly configured firewall, and spammers used
their system to launch e-mail to thousands of people connected to cable
companies' private broadband networks. If I'm paying $40 or $50 a month
for this service, I, as a paying customer do not want to receive
solicitous e-mail (spam) from some one else, especially if they are on the
same broadband network as I. I would complain to my cable company about
it and expect them to do something. It was these exact circumstances that
has led to several people having their cable modems permanently removed.
<blockquote><I>
Current modems are capable of transmitting at 10Mbs in both
directions, but are usually deployed throttled back to a
trasmit speed of 300Kbs and a recieve speed of 1.5Mbs. You
want more bandwidth, they'll be happy to charge you more
money :)
</I> </blockquote> <P>
Personally, I think this is very fair. The cable companies are providing
us with a service. We, as consumers, have to pay for this service. Just
like my electric bill, if I use a lot of electric service, I pay a lot of
money; or like the telephone company, if I have more features or want a
T1, I pay more money than if I only had a normal telephone line. It's
the same with cable modem technology, the capability is there for 10Mbps
bandwidth in both directions. The technology is also there to regulate
that flow. I expect the cable companies to use that technology. If I
want LAN speeds to my house, I should expect to have to pay for it.
<p>
Again, I want to apologize for not clarifying my previous statements a
little more. Please check with your local cable company before you do
anything like connecting your private LAN to theirs. There are as many
different policies as there are cable companies, so make sure to
explicitly ask if what you want to do is permitted. This is a great
technology and has tremendous benefits. Playing by the rules that the
cable company has put in place will only help the technology spread. By
violating the rules, you run the risk of losing access to it, as well as
making it more difficult for the cable comapanies to contiue selling this
service. Like any other market driven product, if there's no money in it,
or it costs too much to implement, it will fall by the wayside, and no one
benefits. By not folling the rules, we as customers can make it cost
prohibitive for implementation, and conversely, by following the rules, we
create more market demand, which in turn, continues pushing the technology
forward, and everyone benefits.
<PRE>
#include &lt;std_disclaimer.h&gt;
</PRE>
I don't pretend to know all the policies of all the cable companies. I
don't assume to speak for any of the,, nor do I tell them how to operate.
My opinions are my own, and no one else's. Dammit Jim, I am a Unix
sysadmin, not a sales rep :)
<p>
Please feel free to send me questions, comments, criticisms, etc.
<p>
Paul
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Thu, 5 Feb 1998 15:01:30 -0500<BR>
From: Jack Chaney, <A HREF="mailto:JAC14@chrysler.com">
JAC14@chrysler.com</A><BR>
Subject: <B>New Direction</B>
<p>
I heard on the radio last night, an announcement that IBM has just
successfully masked, produced and tested their newest piece of
silicon. The processor is based on the PowerPC design and is reported
to run at 1000MHz. Knowing what I know about the PowerPC and its
various flavours, I think it would do to examine the idea of porting
Linux in a native coded version to this processor platform. The
pricing of this chip with a heavy duty operating environment could give
the Alpha a real run for its money.
<p>
The PowerPC (for those who don't know) is a RISC based processor with
three major operation blocks, each capable of independent operation.
This enables the instruction flow to become parallelized so as many as
three instructions can be done simultaneously, and because it is a RISC
processor the instructions have been optimised so most occur in only
one or two cycles. The other element of the design is to have an
extremely large cache memory on-board the processor to reduce fetch
time for instructions. To give an idea of the improvement in speed
realised by this method, a PowerPC emulates the Intel part by keeping
an interpreter block in the cache memory of the chip and interprets the
Intel object code at comparable speeds of the Intel parts. The lure of
creating a native Linux for this processor has crossed my mind on a
number of occasions prior to the IBM announcement, and now I hope with
encouragement this can move from fantasy to fact.
<p>
Jack Chaney
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Fri, 6 Feb 1998 08:50:00 -0500 <BR>
From: Hampton, Mike, <A HREF="mailto:hamptom1@INDY.NAVY.MIL">
hamptom1@INDY.NAVY.MIL</A> <BR>
Subject: <B>Picking a nit</B>
<p>
Maybe I should have called the subject of this "pet peeve" or something
like that. What I am writing about is a simple grammatical error that I
have seen many people make, but one that shouldn't appear in the Gazette
or any published effort and that is the incorrect use of "it's" when the
author should have used "its." An example is in the following sentence
from a recent issue:
<p>
"This was necessary in order for a *nix version to behave to
applications like it's counterparts so applications could run
everywhere."
<p>
If you take the "it's" and expand it, the sentence would read:
<p>
"This was necessary in order for a *nix version to behave to
applications like it is counterparts so applications could run
everywhere."
<p>
The sentence no longer makes sense. Authors should remember that "it's"
is a contraction of "it is." If they want a possessive of "it," they
should use "its." I have also seen instances of authors using the
apostrophe-s when they intended to form a plural but made a possesive
instead (for example, using menu's, a possesive, instead of menus, the
proper plural form). Like I said before, these are very simple and
common errors, but ones which I feel can hurt the author's credibility.
<p>
Before anybody gets too defensive, let me say that as an employee of a
major defense contractor, I have made the above error and have had it
pointed out to me. Maybe that's why it stands out so much when I see it
now.
<p>
Now I'll put down my pen and let others point out my errors.
<p>
Mike Hampton
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Fri, 06 Feb 1998 08:12:09 -0600<BR>
From: Tyree Gwyn, <A HREF="mailto:bounti@myriad.net">
bounti@myriad.net</A> <BR>
Subject: <B>love your site!!</B>
<p>
i very much enjoy the information found on LG!! even though i am posting
from a windows machine, i use linux(redhat 5.0) the majority of the
time. i just happen to be at work, at this time.
<p>
anyway, being a newbie to this whole linux scheme, i have used your
site, dejanews, oreilly books, and many howto's to get my system up to
my specs. linux is very exciting, and has alot of promise. please keep
up the good work.
<p>
Tyree
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Sun, 08 Feb 98 17:34:41 -0500<BR>
From: Leon C. Isaacson, <A HREF="mailto:lci2@global.co.za">
lci2@global.co.za</A> <BR>
Subject: <B>Incomplete Book Reviews</B>
<p>
In Linux Gazette 25, the review of "A Practical Guide to Linux" , by Mark
Sobell, fails to supply the publishers name, publication date, and price. I
enjoyed the review, but surely this information should be included as a
matter of course. Given your reviewers laudatory comments, how or where can
the rest of us hope to acquire this book?
<p>
Leon
<blockquote> <I>
(I agree. He should have included that information. Here's what I know:
<BR>
Publisher: Addison Wesley Longman, info@awl.com, http://www.awl.com/<BR>
Price: $38.00 US<BR>
ISBN: 0-201-89549-B<BR>
-- Editor)</I> </blockquote>
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Fri, 21 Nov 1997 18:59:53 -0500<BR>
From: Timothy D. Gray, <A
HREF="mailto:timgray@lambdanet.com">timgray@lambdanet.com </A>
Subject: <B>Getting Linux to the public...</B>
<P>
Has anyone noticed that when your friends see your neat-o Linux system
with the nice 17 inch monitor, high quality video card, and fast
computer that when they say, "Wow! that is nice, and you can do almost
anything on that!" you cringe with the fact that they are going to want
you to put it on their system? now mind you, I dont cringe on sharing
the best O/S on the planet, In fact I want everyone to use Linux. It's
just that almost all X windows software is written for 1024 X 768 or
higher resolution video screens and that 99% of those wanting to use
Linux and X windows only have a 14" monitor that can barely get past
640X480 at 256 colors. I tried several times to get friends into Linux
and X but to no avail because the software developed for X is for those
that have Gobs of money for good video boards and humoungous monitors.
It's not a limitation of Linux or X, it that the software that is
developed for these platforms are by professionals or professional users
that can afford that new 21 inch monitor at the computer store. We as a
group might want to see software scaled back to the 640X480 crowd.. then
Linux would take the world by storm.. Until then It's going to be
limited to us pioneers and Scientists...
<P>
Tim Gray
<P> <HR> <P>
<!--====================================================================-->
<IMG ALT=" " SRC="../gx/envelope.gif">
Date: Wed, 25 Feb 1998 15:42:09 +0000<BR>
From: Jaime E. Villate,<A
HREF="mailto:villate@fe.up.pt">villate@fe.up.pt</A><BR>
Subject: <B>uptime record</B>
<P>
In Issue 25 (February 98) Sean Horan wrote about a Linux
system that ran continously for 274 days. Here is a quote
from Bruce Perens (president of Debian, works at Pixar) that
I took from http://www.debian.org
<blockquote>
"I thought three months without a reboot was a big deal.
When I mentioned it to our developers, one of them showed
me details about his system. It was up for 458 days, and was
halted to move it to another floor. The network and disk
device drivers had handled tens of millions of interrupts in
that time."
</blockquote>
It would be interesting to know what the record is for other
operating systems older than Linux.
<P>
Jaime Villate, University of Porto, Portugal<BR>
http://www.fe.up.pt/~villate/
<P> <hr> <P>
<!--================================================================-->
<center>Published in <i>Linux Gazette</i> Issue 26, March 1998</center>
<!--====================================================================-->
<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_tips26.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; 1998 Specialized Systems Consultants, Inc. </H5>
<P>
<H4>"Linux Gazette...<I>making Linux just a little more fun!</I>"
</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_tips26.html#apache">Apache SSL extensions...</a>
<li><a HREF="./lg_tips26.html#locate">Locate</a>
<li><a HREF="./lg_tips26.html#print">Re: Printing Problems</a>
<li><a HREF="./lg_tips26.html#net">Re: LG25, Netscape on the Desktop</a>
<li><a HREF="./lg_tips26.html#vax">Re: Linux and VAX 3400 and 3300</a>
<li><a HREF="./lg_tips26.html#binary">Binary File Access with dd</a>
<li><a HREF="./lg_tips26.html#find">Follow up to find 2c-tip</a>
<li><a HREF="./lg_tips26.html#ispell">ispell & Pine 3.96</a>
<li><a HREF="./lg_tips26.html#xvscan">XVSCAN: Combining different parts
together </A>
<li><a HREF="./lg_tips26.html#scape">2c-tip: Netscape on the Desktop</A>
<li><a HREF="./lg_tips26.html#win">Linux and Win95</A>
<li><a HREF="./lg_tips26.html#su">My $0.02 tip: Graphical su</A>
<li><a HREF="./lg_tips26.html#eggs">Easter Eggs in Netscape</A>
<li><a HREF="./lg_tips26.html#core">Core Dumps</A>
</ul>
<P> <hr> <P>
<!--================================================================-->
<a name="apache"></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Apache SSL extensions...
</H3>
Date: Fri, 27 Feb 1998 15:49:41 -0800<BR>
From: Glenn D'mello, <A HREF="mailto:glenn@arbornet.org">
glenn@arbornet.org</A> <BR>
<blockquote> <I>
From Frank:
My problem is this one ... I've gone bananas in trying to find a
document that explains how to install, in a step by step fashion, the
Apache
SSL "extensions" to one of my Apache WWW Webservers (the performance
increase is awesome) can you or anyone that reads this
help... </I> </blockquote>
<P>
This is how I did it:
<ol>
<li>Get SSLeay 0.8.0 or later from
ftp://ftp.psy.uq.oz.au/pub/Crypto/SSL
<li>Build and test and install it!
<li>Get Apache 1.2.5 source
<li>Get Apache SSLeay extensions from
ftp://ftp.ox.ac.uk/pub/crypto/SSL/apache_1.2.5+ssl_1.13.tar.gz
<li>Unpack it in the apache-1.2.5 source directory and patch Apache as
per the README.
<li>Configure and build it.
<li>Read the docs before building (set your paths, etc, etc)
</ol>
Worked the first time too!
Hope this helps:
<P>
Glenn.
<P> <hr> <P>
<!--================================================================-->
<a name="locate"></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Locate
</H3>
From: John Corey, <A HREF="mailto:norm@comanche.dyn.ml.org">
norm@comanche.dyn.ml.org</A>
<P>
One of my annoyances with the locate program have been that with it,
users can see files they have no access to otherwise. So, I have
deviced a little <A HREF="./locate.diff">patch</A> to the original
sources to fix that, along with a
few other annoyances. It inherently does a few other things as well.
It will only list files that do currently exist (not just files that
existed when updatedb was last run). Also, it adds the option -l to
locate which simply performs a ls -l on the files returned.
<P>
To compile, get the sources from
ftp://prep.ai.mit.edu/pub/gnu/findutils-4.1.tar.gz .
Extract that, then apply the attached diff to it with: patch <
locate.diff, and compile per the instructions within findutils.
<P>
The only file modified is locate.c, so you can skip the installation
process if you already have updatedb/locate installed, and just simply
replace your existing locate binary with the new one (keeping a backup
of the original, should anything evil happen).
<P>
Enjoy
<P> <hr> <P>
<!--================================================================-->
<a name="print"></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Re: Printing Problems
</H3>
<P>
Date: Wed, 04 Feb 1998 22:05:40 +0100 <BR>
From: M.H.M. Verhoeven, <A HREF="mailto:leeuweri@stad.dsl.nl">
leeuweri@stad.dsl.nl</A>
<blockquote> <I>
Anyone that can help me. I'd love to hear it. I try running
lpr, but everytime I get no name for local machine.
How do I set this and/or what is the problem.
-- Manish Oberoi </I> </blockquote>
<p>
I had the same problems with printing (no name for local machine).
You should put a entry for your machine in /etc/hosts, and your problem
is solved. In my case, the name of my computer had changed, but
/etc/hosts still contained the old name for my machine.
<p>
Gertjan
<P> <hr> <P>
<!--================================================================-->
<a name="net"></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Re: LG25, Netscape on the Desktop
</H3>
<P>
Date: Thu, 05 Feb 1998 00:26:03 +0100 <BR>
From: Soenke J. Peters, <A HREF="mailto:peters@on-line.de">
peters@on-line.de</A>
<p>
I use a similar trick to start up the browser-/mail-/news-window from
three different buttons in my windowmanager's panel.
For the mail-window, you have to start the script with 'mailbox:' as the
url parameter, for the news-window simply use 'news:'.
For urls beginning different from the above, netscape opens the normal
browser window.
<p>
Soenke J. Peters, Hamburg, Germany
<P> <hr> <P>
<!--================================================================-->
<a name="vax"></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
RE: Linux and VAX 3400 and 3300
</H3>
<P>
Date: Thu, 05 Feb 1998 10:11:00 -0700 <BR>
From: James Gilb, <A HREF="mailto:p27451@email.sps.mot.com">
p27451@email.sps.mot.com</A>
To: dennis.j.smith@ArthurAndersen.com
<blockquote>
<I>I have just purchased a MicroVAX 3400 and 3300. I would like to put Linux
on these two systems. Can you provide any help in this aspect.</I>
</blockquote>
<P>
I believe those are MIPS 3000 boxes, try the Linux VAX Port Homepage at
http://ucnet.canberra.edu.au/~mikal/vaxlinux/home.html and the
Linux/MIPS project at http://lena.fnet.fr/
<p>
My guess is that you will need to get your hands dirty on this one. You
could also try NetBSD, they may have a port now.
<p>
If they are not MIPS boxes, then you could have a real challenge on you
hands, but then isn't that half the fun of Linux?
<p>
James Gilb
<P> <hr> <P>
<!--================================================================-->
<a name="binary"></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Binary File Access with <tt>dd</tt>
</H3>
<p>Date: February 9, 1998<br>
From: Leonard R Budney <a
href="mailto:budney@fore.com">lbudney@fore.com</a><br></p>
<p><tt>dd</tt> stands for <em>Disk Dump.</em> Or if it doesn't it
should. The "main" use for <tt>dd</tt> is to duplicate a floppy
disk, bit for bit, to a file. You probably used it to create boot
disks when you installed Linux for the first time, unless you used
its much less functional cousin <tt>rawrite.</tt> If you're sick of
keeping boxes of floppies around, you can use <tt>dd</tt> in
reverse, and throw the floppy away. Depending on permissions, you
might have to do this as root.</p>
<pre>dd if=/dev/fd0 of=quicken_install_disk_1.img bs=1440k</pre>
<p>The <tt>if</tt> argument specifies an input file (which defaults
to the standard input). Naturally, the <tt>of</tt> argument names
the output file (which defaults to the standard output). Finally,
the <tt>bs</tt> argument tells <tt>dd</tt> what <em>block size</em>
to use. Here we set the block size equal to the size of a floppy
disk, and let <tt>dd</tt> read one block of data.</p>
<p>The man page says that the purpose of <tt>dd</tt> is to "convert
a file while copying it." In English, that means that <tt>dd</tt>
does <em>not</em> assume a file is made of text! It doesn't look
for carriage returns to delimit lines, it doesn't stop reading at
the first binary zero, nothing! This gives us the power to read
files exactly, byte for byte. It allows us to read a fixed number
of bytes, or physically to overwrite a file.</p>
<p>As just one example, consider /dev/random. That's a nifty Linux
innovation--a pseudo device that accumulates randomness. Would you
like to read 10 bytes of random data from /dev/random? It's a
snap.</p>
<pre>dd if=/dev/random of=/tmp/random.bin bs=1 count=10</pre>
<p>Note that /dev/random provides binary data, so if we omit the
<tt>of</tt> argument then that data will probably trash our display.
Alternately, we could have omitted the <tt>of</tt> argument, but
piped the output through <tt>cat -v</tt> to escape any non-printable
characters. In addition to the arguments explained above, we use
the <tt>count</tt> argument to specify the number of blocks to read.
In conjunction with a blocksize of 1, <tt>count=10</tt> tells
<tt>dd</tt> to read exactly 10 bytes.</p>
<p>Here's a final example, for the paranoid. When you delete a file
using <tt>rm,</tt> you only delete the inode pointing to your data.
The data is still there, on the disk, waiting for somebody with a
"Disk Doctor" utility to resurrect and read. Does that bother you?
Well, you should delete your data, not just your file. Again,
<tt>dd</tt> comes to the rescue. Normally <tt>dd</tt>
<em>truncates</em> its output file before writing. The argument
<tt>conv=notrunc</tt> overrides that behavior, and causes
<tt>dd</tt> to write over any existing data. The following shell
script combines all of these ideas, and wipes out your file by
overwriting it five times with pseudorandom data, and then deleting
it.</p>
<pre>
#!/bin/sh
FILE=$1
SIZE=`ls -l $FILE | awk -- '{print \$5;}'`
{
for iteration in 1 2 3 4 5
do
dd if=/dev/urandom of=$FILE bs=${SIZE} count=1 conv=notrunc
sync
done
} && rm -f $FILE
</pre>
<p>Enjoy!<br>
Len.</p>
<P> <hr> <P>
<!--================================================================-->
<a name="find"></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Follow-up to find 2c-tip
</H3>
<P>
Date: Tue, 10 Feb 1998 19:20:44 +0000 <BR>
From: Markus Pilzecker, <A HREF="mailto:mp@rhein-neckar.netsurf.de">
mp@rhein-neckar.netsurf.de</A>
<p>
in your December issue, one of the 2-cents about find had been:
<p><blockquote>
<I>A shorter and more efficient way of doing it uses backticks:</I><BR>
<tt> grep "string" `find . -type f`</tt><BR>
<I>Note however, that if the find matches a large number of files you
may exceed a command line buffer in the shell and cause it to
complain. </I> </blockquote>
<p>
The solution to this is using xargs:
<pre>
find &lt;find_roots&gt; &lt;other_options&gt; -print0 | xargs -0 grep &lt;options&gt;
</pre>
. xargs only puts as much onto grep's [or whatever else's]
command line as fits without overflow. Only in the latter case will
it start a new instance of grep. The trick of the first proposal to
add ``/dev/null'' to grep's command line to make it print the name
of the file in work is [mostly] superfluous then, since xargs
[mostly] puts more than one filename onto grep's command line.
<p>
The find option ``-print0'' and the xargs option ``-0'' work together
to assure correct handling of odd filenames.
<p>
Markus
<P> <hr> <P>
<!--================================================================-->
<a name="ispell"></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
ispell & Pine 3.96
</H3>
<P>
Date: Fri, 13 Feb 1998 08:39:34 -0800 (PST) <BR>
From: Peter Struijk
<p>
To use ispell in Pine, go into Pine SETUP (press S, then C),
search using WhereIs for "speller" (press W) and make sure the value
set there is "ispell". That will do it.
<P>
Peter
<P> <hr> <P>
<!--================================================================-->
<a name="xvscan"></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
XVSCAN: Combining different parts together
</H3>
<P>
Date: Sat, 13 Sep 1997 01:04:29 -0500<BR>
From: Earl Fryman, <A HREF="mailto:fryman@io.com">fryman@io.com</A> <BR>
To: xvscanlist@tummy.com
<P>
<blockquote> <I>
Is it possible to combine two (or more) different parts from
different pages on same fig?
For example, if I scan pages and want to print transparencies from
small part of the text enlarged. Now, if the part 1 is at the end of a
page and the part 2 is on the following page, I have not been able
to combine them on one single fig (part 1 and below it part 2).
How could I do that with xvscan? If the parts are on the same page I have
used cut, past and crop.<BR>
--<BR>
Juha Perkkio, juha.perkkio@mikkeliamk.fi
</I> </blockquote>
<P>
Yes it is posible. Load the first image and select the portion of
the image to cut. Press Alt-C (hold down Alt key and press C).
Load the second image and press Alt-V. A frame window the size
of the cut in the first image will appear. Position the frame where
you want the image to be pasted, then press Alt-V (again). This even
works if the two image are of different type (bmp, jpg, gif, etc.).
<P>
Earl Fryman
<P> <hr> <P>
<!--================================================================-->
<a name="scape"></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
2c-tip: Netscape on the Desktop
</H3>
<P>
Date: Sun, 15 Feb 1998 19:43:58 -0100<BR>
From: Victor-A. Bruessow, <A HREF="mailto:Christian.Bruessow@t-online.de">
Christian.Bruessow@t-online.de</A>
<P>
I'm using this little bash script to start Netscape:
<pre>
#!/bin/sh
if [ $1 ] ; then
REMOTE_COMMAND="openURL($@,new-window)"
else
REMOTE_COMMAND="openBrowser"
fi
netscape -remote $REMOTE_COMMAND || netscape $@
</PRE>
I think it has some advantages over the script from Tim Hawes:
<ul>
<li>no need to look for a lock file, which means:
<li>it even starts Netscape, if there is a stale lock file from a crashed
browser session :-)
<li>you can call it without any arguments, it doesn't matter if there is
a running Netscape or not
("openURL($@,new-window)" will cause an error, if "$@" is empty, so I
use "openBrowser" instead)
</ul>
Christian
<P> <hr> <P>
<!--================================================================-->
<a name="win"></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Linux and Win95
</H3>
<P>
Date: Wed, 18 Feb 1998 14:55:22 +1300<BR>
From: Justin Lodge, <A HREF="mailto:justin.lodge@optimation.co.nz">
justin.lodge@optimation.co.nz</A>
<P>
Rexson
Re: Your Question e-mail to Linux Gazette
<P>
Your big problem is that Win95 has probably helped itself to the entire
drive already - so there is no space left available to install extra
Linux partitions.
<P>
What you really should do first is to back up all the existing
partitions using a tape or a Zip or a Jaz drive. Let me guess you don't
have one of these..... if you can beg/borrow/steal one temporarily and
back everything up before you do anything that would be good.
<P>
Maybe your D: partition doesn't hold much and you can transfer the data
to the C: drive where Win95 is installed - this will allow you to re-use
the D: partition for Linux.
<P>
Next - buy/beg/borrow/steal a recent copy of Red Hat for Linux (make
sure you get the book and the floppy disks that come with the CD) and
the Doctor Linux book.
<P>
Red Hat has a beginners book with it that explains a lot that you need
to know to install Linux and a set of excellent scripts that lead you
though the installation.
<P>
doctor linux has good beginners sections and more complex ones about
dual booting Win95 and Linux
<P>
I would recommend that you DO NOT try to make the machine dual boot - it
could cock-up the win95 installation
but these articles will help you understand the mechanics around this
area. The HOWTO articles in Doctor Linux are all available on the
Internet if you don't want to buy a book but having a hard copy to
reference is much easier.
<P>
once you have re-located any useful data off the D: to the C: then use
the disk partitioning tool that comes with red hat to de-allocate the D:
partition and then create the root, usr, swap and home (and any others)
in this area. From memory I believe that the root partition has to be in
a primary partition but all the rest can be logical partitions contained
in a single "extended" partition.
<P>
This re-allocation of partitions is EXTREMELY dicey - make absolutely
sure you understand which partition is C: and which is D: IF you
de-allocate C by mistake then it is almost definitely un-recoverable
unless you have Norton for Win95 or something similar that can repair
the damage.
<P>
Create a boot diskette using red hat so that when you want to run Linux
you just plug it in and re-boot the machine - booting off the floppy may
seem awkward but it is much much faster than any version of Windoze.
<P>
Any one else using the family using the machine will not have this boot
diskette and will not be able to see your
partitions from Win95 and won't even know that Linux is there. This is
how I keep my family off my copy of Linux.
<P>
Justin
<P> <hr> <P>
<!--================================================================-->
<a name="su"></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
My $0.02 tip: Graphical su
</H3>
<P>
Date: Wed, 18 Feb 1998 22:01:25 +0100 (CET)<BR>
From: Andreas Kostyrka, <A HREF="mailto:andreas@rainbow.studorg.tuwien.ac.at">
andreas@rainbow.studorg.tuwien.ac.at</A>
<P>
Sometimes one want to do su but be able to use X11 programs like RH
control-panel. There are several ways to accomplish this:
*) The hard way: su - and copy&paste the xauth:
<PRE>
$ xauth list $DISPLAY # mark the output
$ su -
# xauth add &lt;paste the above line&gt;
# export DISPLAY=&lt;display mentioned in the pasted line.)
</PRE> <P>
*) The overkill net way:
<PRE>
$ ssh localhost -l root
</PRE> <P>
This depends upon you haveing installed ssh (ftp.replay.com is the site
where one gets the crypto stuff for RH Linux in .rpms), and is probably
not that fast, as it uses a X11 proxy forwarding server.
<P>
*) The graphical (XDM) way, or the way to show off for your WinNT friends:
<PRE>
$ Xnest :10 -query localhost &
</PRE>
:10 must be perhaps customized if it is already in use.
localhost is your xdm host.
This should work if you use xdm for login. (==You have a graphical login
screen.)
<P>
Andreas Kostyrka
<P> <hr> <P>
<!--================================================================-->
<a name="eggs"></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Easter Eggs in Netscape
</H3>
<P>
Date: Wed, 18 Feb 1998 13:32:57 -0800 (PST)<BR>
From: Eric Geyer, <A HREF="mailto:corduroy@sfo.com">corduroy@sfo.com</A>
<P>
I saw the list of Easter Eggs in Netscape, and I have two more, both much less
useful than the ones you listed.
<PRE>
about:mozilla
</PRE>
On all the Unix netscapes I've seen, it changes the Netscape logo in the upper
right.
<PRE>
about:jzw
</PRE>
This will take you to Jamie Zawinski's homepage, and will change the Netscape
logo on Unix netscape except for version 4.
<P>
Just thought you would like to know...
<P>
Eric Geyer
<P> <hr> <P>
<!--================================================================-->
<a name="core"></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
Core Dumps
</H3>
<P>
Date: Thu, 19 Feb 1998 13:56:51 PST<BR>
From: Marty Leisner, <A
HREF="mailto:leisner@sdsp.mc.xerox.com">leisner@sdsp.mc.xerox.com</A>
<P>
I was annoyed on Linux that file(1) couldn't tell what file
dumped core if a core dump was seen.
<P>
For a while, I was doing strings | head and guess at it by inspection.
<P>
But size will do the job:
<PRE>
: leisner@dw;size core
text data bss dec hex filename
45056 295036 0 340092 5307c core (core file invoked as minicom - dpp2)
</PRE>
<P>
marty
<P> <hr> <P>
<!--================================================================-->
<center>Published in <I>Linux Gazette</I> Issue 26, March 1998</center>
<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_mail26.html"><IMG SRC="../gx/back2.gif" ALT=" Back "></A>
<A HREF="./lg_bytes26.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; 1998 Specialized Systems Consultants, Inc. </H5>
<P>
<H4>"Linux Gazette...<I>making Linux just a little more fun!</I>"</H4>
<HR>
<center>
<table cellpadding=7><tr><td>
<IMG SRC="../gx/bytes.gif" border=1 ALT="News Bytes">
</td><td>
<H3>Contents:</H3>
<ul>
<li><a HREF="./lg_bytes26.html#general">News in General</a>
<li><a HREF="./lg_bytes26.html#software">Software Announcements</a>
</ul>
</td></tr></table>
</center>
<a name="general"></a>
<p><hr><p>
<!-- =================================================================== -->
<center><H3> News in General </H3></center>
<P> <hr> <P>
<!-- =================================================================== -->
<center><IMG ALT=" " SRC="./gx/cover48.jpg"></center>
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
April <I>Linux Journal</I>
</H3>
<P>
The April issue of <A HREF="http://www.linuxjournal.com/"><I>Linux
Journal</I></A> will be hitting the newsstands March 6.
The focus of this issue is Workplace Solutions with
articles on Marketing Linux, WordPerfect 7, Satellite Remote Sensing,
Linux in Biomedical Labs and much more. Check out the
<A HREF="http://www.ssc.com/lj/issue48/index.html">Table of Contents</A>.
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
Washington, DC Linux Users Group InstallFest
</H3>
<p>
1 Feb 1998 <BR>
On March 28, 1998, the Washington DC area Linux User Group (DC LUG)
will have its next Linux Installation Fest. Volunteer experts from
several local Linux user groups will assist computer users interested
in trying out Linux, the operating system that Byte Magazine, Wired,
PC Magazine and other industry publications agree is a significant
software phenomenon. Bring your PC and leave with Linux co-installed,
or just visit the demo room to see what Linux is all about.
<p>
Started as an exercise in Internet-based collaboration among hundreds
of software developers around the globe, Linux has acquired a
reputation for superior power and robustness, along with a
relentless pace of improvements, a combination rarely matched by the
mainstream software Unix and Windows NT industry.
<p>
Linux has attracted an estimated 3 to 15 million users, and also
garnered commercial support, evidenced by several shrinkwrap vendors
with shelf space in mass-market computer stores. Even though in
most cases an installation of Linux is a simple procedure, DC LUG
will help those who may have unusual configurations or simply
some trepidations about jumping in. Representatives from RedHat
Software, one of Linux vendors, will also attend and provide advice.
<p>
The InstallFest will be held at the Uniformed Services University of
the Health Sciences, the medical school at the Bethesda Naval Medical
complex, just inside the Beltway between Wisconsin and Connecticut
Avenues.
<p>
Doors open at 10 AM through 4 PM, Saturday 28 March 1998. See
http://www.tux.org/fest for details and a requested pre-registration
form.
<p>
For more information: <BR>
David Lesher, <A HREF="mailto:wb8foz@nrk.com">wb8foz@nrk.com</A>, (301)
608-9775<BR>
Przemek Klosowski, <A HREF="mailto:przemek@tux.org">przemek@tux.org</A>, (301) 975-6249
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
Linux in the News
</H3>
A new spot to get Linux news information is <A
HREF="http://www.eklektix.com/lwn/">http://www.eklektix.com/lwn/</A>, and
don't forget <A HREF="http://www.linuxhq.com/">http://www.linuxhq.com/</A>.
<p>
<I>Linux for Dummies</I> by Jon "maddog" Hall and others and <I>Linux for
Dummies Quick Reference</I> by Phil Hughes are out from IDG books. Get your
copy today.
<P>
InfoWorld's 02/02/98 issue names Red Hat Linux 5.0 as it's OS of the year
for 1997. The article can be found on-line at
<A
HREF="http://www.infoworld.com/cgi-bin/displayArchive.pl?/98/05/poy2a.dat.htm">
http://www.infoworld.com/cgi-bin/displayArchive.pl?/98/05/poy2a.dat.htm</A>
under the Operating Systems heading.<BR>
<A HREF="./redhat1.html">Red Hat's Press Release</A>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
Debian Year 2000 Compliance
</H3>
<p>
1 Feb 1998 <BR>
Debian's Y2K compliance statement is at
<A HREF="http://www.debian.org/news.html#19980104">
http://www.debian.org/news.html#19980104</A>
<P>
For more information: <BR>
Bruce Perens, <A HREF="mailto:bruce@pixar.com">bruce@pixar.com</A>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
"open source" -- new term for libre software
</H3>
<p>
10 Feb 1998<BR>
<A HREF="./perens.html">The Open Source Definition</A>by Bruce Perens
<p>
<A HREF="http://earthspace.net/~esr/open-source.html">
Goodbye, "free software"; hello, "open source"</A> by Eric Raymond
<P>
For more information: <BR>
<A HREF="http://www.opensource.org/">http://www.opensource.org/</A>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
Linux receives the Softwarove noviny "Product of the year" award
</H3>
<p>
1 Feb 1998 <BR>
Date: Mon, 9 Feb 1998 13:53:30 GMT
<p>
The Czech computer monthly "Softwarove noviny" awarded the Linux 2.0
operating system with its award "Product of the Year 1997". This award
is regularly (for the sixth time this year) assigned to the best
computer products available on the Czech market without any other
limitation. The "Product of the Year" award is strictly non-commercial,
no fee is paid and no application is put in. Among the criteria is
technical excellence, amount of innovation, price / performance ratio
as well as the amount of value added by the domestic vendor. The award
was granted to 18 products for the past year, among them two operating
systems.
<p>
Softwarove noviny (www.softnov.cz) is a prestigious Czech computer monthly.
Its name (with meaning Software News) is rather traditional than descriptive:
actually it is a generally oriented computer magazine that focuses on
software as well as hardware, networking and other aspects of IT
market. It is published in Czech language and distributed in both Czech
and Slovak Republics. The Softwarove noviny reader?s group includes
professional IT users, entrepreneurs and managers. The Softwarove
noviny is the only Czech computer monthly prepared entirely from
domestic sources without translated articles from American or German
industry press. Softwarove noviny magazine publishes now 16,000 copies
(total population of Czech Republic is 10 million), 85 % of which are
paid (1/3 by subscribers). About 40 % of the magazine are occupied by
advertisements of both Czech and worldwide IT companies. According the
independent surveys from November 1996, the Softwarov&eacute; noviny magazine
is the most known IT magazine in the Czech Republic.
<p>
The WWW page of Softwarove noviny is available at http://www.softnov.cz/.
The Czech Linux Users' Group has its WWW page at http://www.linux.cz/czlug/.
<p>
For more information: <BR>
Jan "Yenya" Kasprzak, <A HREF="mailto:kas@informatics.muni.cz">
kas@informatics.muni.cz</A>, <A HREF="http://www.fi.muni.cz/~kas/">
http://www.fi.muni.cz/~kas/</A>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
WWW: inofficial StarOffice 4.0 for Linux FAQ
</H3>
<p>
16 Feb 1998<BR>
Michael Hoennig has collected some questions and answers into an
inofficial FAQ of Linux (and some UNIX-) specific topics of StarOffice
4.0. This FAQ in the German language can be found at:
<p>
http://www.on-line.de/~michael.hoennig/soffice4-linux-faq-49.html
<p>
This FAQ in an English version can be found at:
<p>
http://www.on-line.de/~michael.hoennig/soffice4-linux-faq-01.html
<p>
For more information: <BR>
Michael Hoennig, <A HREF="mailto:mhoennig@on-line.de">mhoennig@on-line.de</A>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
WANTED: Project LEAP: Linux-Equipped Astronauts Project
</H3>
<p>
1 Feb 1998 <BR>
<p>
17 Feb 1998<BR>
Recent articles on the International Space Station (ISS) have
mentioned that astronauts will be issued laptop computers running
MSWin95. Other reports have predicted disastrous trouble with
the station control software, because of poor engineering practices
and unrealistic schedules.
<p>
This situation creates a real opportunity for Linux. While we
(probably) can't help with the main station software, at least
the astronauts can be freed from Win95 crashes. Imagine the sound
bites: "At least our laptops don't crash all the time."
<p>
PEAL is a project to port the applications that the astronauts use
to run under Linux, so each astronaut has a choice of operating
systems. Many of them will continue using MSWin95, for a time, but
if any astronaut chooses Linux, the others will begin to pick it up,
just as happens on the ground.
<p>
Anyone who wants to take over the
web page, design a project logo, set up a mail reflector, create a
newsgroup, become group leader, or (almost forgot :-) port software,
please write. We need to know what codes the astronauts need ported,
and where the sources are. The project web page, for now, is:
<p>
<A
HREF="http://www.cantrip.org/leap.html">http://www.cantrip.org/leap.html</A>
<p>
For more information: <BR>
Nathan Myers, <A
HREF="mailto:ncm@nospam.cantrip.org">ncm@nospam.cantrip.org</A>,
<A HREF="http://www.cantrip.org/">http://www.cantrip.org/</A>
<P> <hr> <P>
<!-- =================================================================== -->
<a name="linuxexpo"></a>
<img align="right" src="../gx/linuxexpo.gif">
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
4th Annual Linux Expo, May 28-30th
</H3>
<p>
February 17, 1998:<BR>
Linux is making waves in the news, and now is the
opportunity for the world to find out why. It's time to get ready for
the largest gathering of the best and brightest minds in the computer
world. For three business-centered and technology-packed days, May
28-30, the fourth annual Linux Expo will take over Duke University in
Durham, North Carolina.
<p>
This year's Linux Expo is shaping up to be a can't-miss event. Visit
the record number of Expo exhibitors (there is still time for your
company to become involved) showing the latest in Linux-based hardware,
software, and service solutions. And stop in on the business and technical
discussions to hear talks by some of the most important names in technology
today.
<p>
Yes, Linus Torvalds will be there. And so will many others.
<p>
Technical track speakers include:
<ul><li>
*Eric Youngdale - Future Directions of Linux SCSI Development
<li>
*Dirk H Hohndel - XSuSE -- adding more to the XFree86 offerings
<li>
*Frank T. Kujawski - Setting Up Diskless Computers, Quickly!
<li>
*Simon Horman - Creating Redundant Servers in Linux
<li>
*Jacques Gelinas - LinuxConf
<li>
*Alan Cox - "I don't care if space aliens ate my mouse" or Porting
Linux to the Apple Macintosh 68K
<li>
*Mike Westall - ATM Device Driver Development in Linux
<li>
*Jes Sorensen - Linux/HIPPI - Linux Joins Supoercomputing Networking
<li>
*Bruce Perens - The Computer Graphics of Pixar
<li>
*Lars Wirzenius - Linux Anecdotes
<li>
*Greg Badros - A Caching NFS Client for Linux
<li>
*Eric S. Raymond - Homesteading the Noosphere: Custom and Property
Rights in the Free Software Community
<li>
*David S. Miller - Optimizing the Cobalt Microserver
<li>
*Miguel de Icaza - GNOME: The GNU Network Object Model Environment
<li>
*Alex "Mr. Worf" Yuriev - Optimizing Network Performance
<li>
*Peter J. Braam - The Linux 2.1 New VFS Interface
<li>
*Steffen Seeger - KGI: Graphics and Games with the Kernel
<li>
*Andreas Beck - LibGGI The next generation fully portable graphics
library
<li>
*Jason McMullan - EvStack - Linux Console Design, Take II
<li>
*Daryll Strauss - Linux helps create Titanic
<li>
*Stephen C. Tweedie - Journalling the Linux Filesystem
<li>
*Peter J. Braam - The Coda Distributed Filesystem on Linux
</ul>
<p>
There will also be Tutorial Sessions featuring among others:
<ul><li>
*Peter J. Braam - Coda Demonstrations
<li>
*Jakub Jelinek - Hacking the Linux Kernel
</ul>
<p>
Business track speakers include:
<ul><li>
*Bruce Perens, Software in the Public Interest--Free Software Licensing
<li>
*Jon maddog Hall, Digital Equipment Corp.-- Linux Around the World
<li>
*James Gray, S.u.S. E.-- A Cooperative Model for Linux Certification
<li>
*Tim Bird, Caldera, Inc.-- The COAS Project
</ul>
<p>
For more information:<BR>
<A HREF="mailto:linux@linuxexpo.org">linux@linuxexpo.org</A>
<A HREF="http://www.linuxexpo.org/">http://www.linuxexpo.org/</A>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
WWW: linux for starters WWW-page
</H3>
<p>
Fri, 20 Feb 1998 08:29:00 GMT<BR>
Here's Yet Another Page Concerning Linux For
Starters. In case anyone's interested...
http://www.ping.be/leminator/leminator.htm
<P>
For more information: <BR>
Koen Janssens, <A HREF="mailto:trott@mail.dma.be">trott@mail.dma.be</A>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
WANTED: OpenBIOS - Freeware x86 BIOS iniatitive
</H3>
<p>
1 Feb 1998 <BR>
<p>
Fri, 20 Feb 1998 08:42:53 GMT<BR>
Some discussion about the possibility of a freeware 'GNU' BIOS
was casually mentioned on the Linux kernel mailing list last week.
Talk about it escalated, and a mailing list was quickly formed.
After a few more days of ideas, it seems like a very good possibility
and some people just hell bent on getting started.
<p>
What we are looking for now are people with a high degree of knowledge
about the low-level workings of the x86 PC architecture, and real mode
programming experience. Please join the mailing list and offer what help
you can.
<p>
Also understand that many Linux people are involved with this, but the
purpose is a COMPLETE BIOS replacement for use with all Intel x86 OS's,
not just some new boot loader.
<p>
To subscribe to the OpenBIOS Mailing list, write an email
To: openbios-request@linkscape.net
Subject [leave blank!]
subscribe [in the body]
It is a majordomo managed list. Feel free to use extended MD commands as needed.
<p>
OpenBIOS web pages: (DO NOT expect to find much here yet! )
<A HREF="http://www.linkscape.net/openbios/">
http://www.linkscape.net/openbios/</A> <BR>
<A HREF="http://www.freiburg.linux.de/OpenBIOS/">
http://www.freiburg.linux.de/OpenBIOS/</A>
<p>
For more information: <BR>
Dave Cinege
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
Linus Torvalds at next SVLUG meeting March 4th
</H3>
<p>
1 Feb 1998 <BR>
<p>
20 Feb 1998 <BR>
March 4, 1998, Linus Torvalds will speak at the Silicon Valley Linux
Users Group (SVLUG) meeting. The meeting begins at 7pm.
<p>
This meeting will be held at our new location, the GateWay Conference
Center, Building J, ciscoSystems. The address for this conference
center is:
<p>
255 W. Tasman Drive <BR>
San Jose, CA 95134
<p>
Please enter through the front entrance of the building, and the
conference center will be to your left. There will be signs.
<p>
For more information: <BR>
Rob Walker, <A HREF="mailto:rob@svlug.org">rob@svlug.org</A><BR>
<A HREF="http://www.svlug.org/">http://www.svlug.org/</A>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
[gtk-list] Qt/KDE Netscape -- An estimate of Work!
</H3>
<p>
1 Feb 1998 <BR>
John McNulty wrote:
I'm sure after Netscape's source code announcement, a number of
people (like me) must have wondered about the possibility of a
port to KDE and/or Qt. So I asked one of the Netscape engineers
for an opinion on this. Below is the answer I got.
<blockquote> <ul>
<li>The GUI frontend is clearly seperated from the rest of the browser
by a well defined API (which all 3 frontends - MFC, Mac, Motif -
use).
<li>There are about 50 widgets ( ls *.c | wc -l) that are Netscape
specific, which'll have to be ported.
<li>The GUI itself is composed of around 160 C++ files, which
instantiate these widgets.
</ul>
Depending on the number of people working on it, it could take
anywhere between 2 months to an year. Of course, stripped down
versions are possible in a shorter period of time.
</blockquote>
<P>
So if anyone put there is thinking about this, you can use
this as a guideline to figure out how much work is involved.
<BR>
--John
<a name="software"></a>
<P> <hr> <P>
<!-- =================================================================== -->
<center><H3> Software Announcements </H3></center>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
ZINC Software
</H3>
<p>
9 Feb 1998<BR>
Zinc's flagship product, Zinc Application Framework, is a very high-
quality C++ GUI API and interface builder which supports popular
desktop operating systems (Windows, Motif, DOS, ...) *and* which is
scalable to embedded platforms as well (in 1/10th the space of
Windows CE!).
<p>
Zinc has recently negotiated distribution agreements with popular
Linux vendors to include ZAF with their CD-ROM distribution. Zinc has
also been engaged by top embedded operating systems' vendors to
provide reference ports of ZAF for their embedded OS.
<p>
For more information: <BR>
Robert Bishop, <A HREF="mailto:rbishop@zinc.com">rbishop@zinc.com</A><BR>
Zinc Software Incorporated, <A
HREF="http://www.zinc.com/">http://www.zinc.com/</A>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
EDA Software: Linux VHDL Simulator Sells Via Web
</H3>
<p>
9 Feb 1998<BR>
Essex Junction, Vt. -- Despite considerable user interest, very
few Linux-based EDA tools have become available. One of the
first is a new Linux version of the Green Mountain Computing
Systems VHDL compiler, available for $169 via the World Wide
Web.
<p>
Green Mountain currently offers a DOS-based VHDL simulator, and
Accolade Design Automation (Duvall, Wash.) sells a Windows-based
version of the same simulator. The new version 2 of the Green
Mountain VHDL compiler supports most, but not all, of the
features of IEEE 1076-87 and 1993 VHDL.
<p>
The Linux version is a port of the DOS version and includes all
the same features, except for the user interface. Both versions
come with two simulation environments for batch or interactive
simulation, precompiled IEEE packages, an online VHDL tutorial,
a Motorola HC11 microcontroller example model and free technical
support via e-mail.
<p>
Scott Thibault, president of Green Mountain Computing Systems,
said he developed the Linux version because that freely
distributed operating system is becoming more important in
universities, which have made up Green Mountain's primary
market. He said the Linux version is slightly slower than the
DOS version because of its support for multitasking.
<p>
Linux has gained a following because it's viewed as a stable,
robust operating system that gives PCs full Unix compatibility.
Thus, commonly used Unix utilities such as "make" are available.
Linux also has minimal memory requirements. The Green Mountain
Linux VHDL compiler can run in about 8 Mbytes of RAM.
The simulator can be ordered only by mail or over the Internet.
<p>
For more information: <BR>
<A HREF="mailto:Andy@Piziali.dv.org">Andy@Piziali.dv.org</A><BR>
<A HREF="http://together.net/~thibault">http://together.net/~thibault</A>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
EAGLE LINUX M68K
</H3>
<p>
for AMIGA, Atari, Mac 68k and all computers based on the Motorola MC680x0 CPU
is now available. The end user delivery starts the first week of March.
Linux is pre-available on CDR for press and magazines.
<p>
Distribution:<BR>
Eagle Computer Products GmbH,<BR>
S.u.S.E. GmbH
<p>
Update CDs will follow every 2-3 months.
Planned versionen which will come soon:
<ul>
<li>Intel PC Linux
<li>PowerPC Linux
<li>DEC Alpha Linux
</ul>
For more information: <BR>
Dragon Internet Design, Frank Rosendahl & Klaus-Peter Walter
<A HREF="mailto:linux@eagle-cp.com">linux@eagle-cp.com</A> <BR>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
Olicom Linux Token-Ring driver released
</H3>
<P>
6 Feb 1998<BR>
Olicom is pleased to announce the release of a Linux Driver for
Olicom's high performance Token-Ring Adapters OC-3118 and OC-3137. The
driver is also compatible with the older OC-3136 adapter.
The combination of Olicom's Token-Ring adapters and new Linux drivers
provide superior performance in a Linux Token-Ring environment.
<p>
The driver has been tested with the (currently) latest version of the
2.0 kernel, 2.0.33. It will probably work with any 2.0 kernel,
i.e. all of the kernels used by the Linux distributions, but this has
not been tested and can not be guaranteed.
<p>
For the current development versions of Linux 2.1 the driver has been
tested with version 2.1.78. Changes to the development kernel are
occurring in rapid pace and compatibility can not be guaranteed.
<p>
The Olicom Linux driver is available from Olicom's WEB site
http://www.olicom.dk/ (Europe) or http://www.olicom.com/ (US).
<p>
Pre-compiled kernels with the driver builtin - based on Linux 2.0.33 -
for RedHat 4.2, RedHat 5.0 and other systems using the Linux
2.0.x kernel, are available from
<p>
ftp://ftp.olicom.dk/pub/releases/Unix-Driver/Linux/unsupported/
<p>
For more information: <BR>
<A HREF="mailto:henrik_stoerner@olicom.dk">henrik_stoerner@olicom.dk</A><BR>
<A HREF="http://www.olicom.dk/">http://www.olicom.dk/</A> (Europe) <BR>
<A HREF="http://www.olicom.com/">http://www.olicom.com/</A> (US)
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
GNU plotting utilities 2.0 released
</H3>
<p>
6 Feb 1998 <BR>
Release 2.0 of the GNU plotting utilities is now available at
ftp://ftp.gnu.org/pub/gnu/plotutils-2.0.tar.gz . It should soon be
available via ftp from the GNU mirror sites. A list of mirror sites is
appended below; please try them before you try ftp.gnu.org.
<p>
This is a major release. The centerpiece of the package is now `libplot',
a function library for 2-D device-independent graphics. Libplot is
installed as a DLL (dynamically linked library), on systems that support
DLL's. Libplot now supports Hewlett-Packard Graphics Language (HP-GL and
HP-GL/2) output, in addition to Postscript, xfig, Tektronix, and X11 output.
So HP LaserJet and other PCL 5 printers are now supported.
<p>
The manual for the plotting utilities is now over 100 pages long. To
install and print the documentation, be sure that you have the current
release of the GNU texinfo package (v. 3.11) installed on your system.
You may retrieve it from ftp://ftp.gnu.org/pub/gnu/texinfo-3.11.tar.gz .
<p>
For more information: <BR>
Mathematics Department, University of Arizona <BR>
Robert S. Maier, <A
HREF="mailto:rsm@math.arizona.edu">rsm@math.arizona.edu </A>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
Data Plotting Library DISLIN 6.3c
</H3>
<p>
6 Feb 1998<BR>
DISLIN is a high-level and easy to use plotting library for
displaying data as curves, bar graphs, pie charts, 3D-colour plots,
surfaces, contours and maps. Several output formats are supported
such as X11, VGA, PostScript, CGM, HPGL, TIFF and Prescribe. The library
contains about 400 plotting and parameter setting routines and is
available for several C, Fortran 77 and Fortran 90 compilers.
<p>
Version 6.3c of DISLIN is now released for Linux. The supported
compilers are GCC, G77, Imagine F, NAGf90, Absoft f77 and Absoft f90.
Plotting extensions for the programming languages Perl 5.003 and Python
1.5 are included.
<p>
All DISLIN distributions for Linux are free.
DISLIN is available from the DISLIN Home Page:<BR>
<A HREF="http://www.mpae.gwdg.de/dislin/dislin.html">
http://www.mpae.gwdg.de/dislin/dislin.html </A> <BR>
and via FTP from the server:<BR>
<A
HREF="ftp://ftp.gwdg.de/pub/grafik/dislin/">ftp://ftp.gwdg.de/pub/grafik/dislin/</A>
<p>
For more information: <BR>
Max-Planck-Institut fuer Aeronomie<BR>
Helmut Michels, <A
HREF="mailto:michels@linax1.mpae.gwdg.de">michels@linax1.mpae.gwdg.de </A>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
ktalkd-0.4.1 - Enhanced talk daemon
</H3>
<P>
6 Feb 1998<BR>
ktalkd is an enhanced talk daemon with answering machine for Unix systems,
designed to work under KDE, but can also work without it.
It is available at:<BR>
ftp://aurora.resi.insa-lyon.fr/pub/people/dfaure/linux/ktalkd-0.4.1.tgz <BR>
ftp://ftp.kde.org/pub/kde/Incoming/ktalkd-0.4.1.tgz
<p>
Tested on Linux or BSD, with or without KDE.
<p>
For more information: <BR>
David Faure, <A
HREF="mailto:david.faure@ifhamy.insa-lyon.fr">david.faure@ifhamy.insa-lyon.fr</A>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
angela! 1.7 BETA - graph editor w/ Tcl/Tk interface
</H3>
<p>
9 Feb 1998 <BR>
angela! stands for: <pre>
A ngela is a
N atural
G raph
E ditor with
L ayout
A lgorithms
! </pre>
<p>
angela! is free of charge (GPL LICENSE)
<p>
It is intended to help the user creating simple graphs for courses,
technical diagrams or simply demonstrating what graph algorithms can
do.
<p>
The developpment platform is Linux 2.0.32 with glibc libraries as there
are provided with RedHat 5.0. Porting angela! to other systems should not
be difficult as it uses these Programs:
<ul>
<li>Standard C compiler (no C++ code at this time)
<li>CWEB Version 3.4
<li>Tcl/Tk Version 8.0p2
<li>Tix 4.1
</ul>
For binary distributions, only Tcl/Tk Version 8.0p2 and Tix 4.1 are
necessary. Contact your system administrator to help you installing these
tools (also used by other programs, so the disk space is not wasted ;) )
<p>
The actual version is at this time under the following URL:
<p>
<A
HREF="http://www.mpi-sb.mpg.de/~pabst/angela/">http://www.mpi-sb.mpg.de/~pabst/angela/</A>
<p>
For more information: <BR>
Oliver Pabst, <A HREF="mailto:olpa@itm.uni-sb.de">olpa@itm.uni-sb.de</A>
<BR>
University of Saarland, Computing Center, Germany.
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
Tsinvest, version 0.4, stock trading program released.
</H3>
<p>
9 Feb 1998<BR>
The C sources to a stock trading program, tsinvest.tar.gz, version
0.4, are available at <A HREF="ftp://sunsite.unc.edu:/pub/Linux/Incoming/">
ftp://sunsite.unc.edu:/pub/Linux/Incoming/"></A> or
<A HREF="ftp://sunsite.unc.edu:/pub/Linux/apps/financial/investment/">
ftp://sunsite.unc.edu:/pub/Linux/apps/financial/investment/</A>. The
sources are free for non-commercial use.
<p>
The program tsinvest is for quantitative financial analysis of equity
values. An optimal portfolio investment strategy for multiple
equities is computed. The program decides which of all available
equities to invest in at any single time, by calculating the
instantaneous future value of all equities, and using statistical
estimation techniques to estimate the accuracy of the calculated
values. Entropic techniques are used throughout. A tutorial is
presented in the man(1) pages. A companion equity market simulation
program is included.
<p>
For more information: <BR>
John Conover, <A HREF="mailto:conover@netcom.com">conover@netcom.com</A>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
Linux Logo 1.04 - shows system info with a linux logo
</H3>
<P>
9 Feb 1998<BR>
linux_logo outputs a color ansi version of a penguin, accompanied by
system info gathered from proc.
SUPPORTS Linux, SMP, Atari m68k, and even some non-Linux OS's
<p>
USES [instructions included]:
<ul>
<li>Have a boot-up penguin in userspace [avoid kernel bloat]
<li>Impress your friends with a fancy color penguin login/motd
<li>Have a "penguin" port on your computer
<li>Use your imagination!
</ul>
WHERE TO GET LINUX_LOGO:<BR>
http://www.glue.umd.edu/~weave/vmwprod/linux_logo-1.04.tar.gz <BR>
http://sunsite.unc.edu/pub/Linux/Incoming/linux_logo-1.04.tar.gz -- at first
http://sunsite.unc.edu/pub/Linux/logos/penguin/linux_logo-1.04.tar.gz
<p>
Check out other programs at http://www.glue.umd.edu/~weave/vmwprod
<p>
For more information: <BR>
Vince Weaver, <A HREF="mailto:hweave@eng.umd.edu">weave@eng.umd.edu</A>,
<A
HREF="http://www.glue.umd.edu/~weave/">http://www.glue.umd.edu/~weave/</A>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
xfpovray v1.3 - An X interface for POV-Ray raytracer
</H3>
<p>
16 Feb 1998<BR>
I would like to present a new version (1.3) of my xforms
interface to the ray tracer POV-Ray. If you have
ever used POV-Ray from the command line, you might
find this program useful. Check: <BR>
<A
HREF="http://cspar.uah.edu/~mallozzir/">http://cspar.uah.edu/~mallozzir/</A>
<p>
Source code is available in tgz, bzip2, and
rpm formats.
<p>
For more information: <BR>
Robert S. Mallozzi, <A
HREF="mailto:mallors@crazyhorse.msfc.nasa.gov">mallors@crazyhorse.msfc.nasa.gov</A>
<A
HREF="http://cspar.uah.edu/~mallozzir/">http://cspar.uah.edu/~mallozzir/</A> <BR>
University of Alabama
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
Casio Digital Diary Backup/restore v2.2
</H3>
<p>
17 Feb 1998 <BR>
Casio Diary
is a package that allows communication to
the CASIO series of hand-held organizers based on a protocol posted
by Knut Radloff, knut@krhh.hanse.de.
<p>
Version 2.2 has been tested on Linux2.x , Solaris2.x, sunos4.x.
For both the BOSS and ILLUMINATOR models and is released under the GPL.
<p>
It is provided as is i.e. jamal is not to be responsible for any
damages it causes to you, your CASIO or your environment.
<p>
Primary-site: <A HREF="http://sunsite.unc.edu/pub/Linux/apps/comm/">
http://sunsite.unc.edu/pub/Linux/apps/comm/</A> <BR>
100kB casio22.tgz, 1kB casio.lsm
Alternate-site: <A
HREF="ftp://ftp.cyberus.ca/pub/users/hadi/casio/casio22.tgz">
ftp://ftp.cyberus.ca/pub/users/hadi/casio/casio22.tgz</A>
<p>
For more information: <BR>
Jamal Hadi Salim, <A HREF="mailto:hadi@cyberus.ca">hadi@cyberus.ca </A>
<BR>
Ottawa, Canada
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
Telnet98 - updated telnet source distribution
</H3>
<p>
18 Feb 1998<BR>
Telnet98 is a new release of the ubiquitous "telnet" utility, based on
the 1995 MIT telnet distribution from ftp.cray.com and net-dist.mit.edu.
Telnet98 adds some new features to the distribution including
new 'configure' based build and install scripts and
support for additional authentication and encryption types.
<p>
Telnet98 can be downloaded from <A
HREF="ftp://quasimodo.stanford.edu/pub/telnet/">ftp://quasimodo.stanford.edu/pub/telnet/</A>,
and US/Canadian users can find instructions there for downloading source
with strong (128-bit) encryption enabled.
<p>
For more information: <BR>
Thomas Wu, <A
HREF="mailto:tjw@xenon.stanford.edu">tjw@xenon.stanford.edu</A> <BR>
Stanford University: Computer Science Department, CA USA
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
Subject: fetchmail-4.3.7 - mail retriever for POP and IMAP
</H3>
<P>
18 Feb 1998<BR>
The 4.3.7 release of fetchmail is now available at the usual locations,
including <A
HREF="http://earthspace.net/~esr/fetchmail/">http://earthspace.net/~esr/fetchmail/</A>. Here are the release
<p>
For more information: <BR>
Eric S. Raymond, <A
HREF="mailto:esr@snark.thyrsus.com">esr@snark.thyrsus.com</A> <BR>
Organization: Eric Conspiracy Secret Labs,
<a href="http://earthspace.net/~esr">http://earthspace.net/~esr</a>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
leap 1.1.9 - A free RDBMS
</H3>
<p>
20 Feb 1998<BR>
<p>
LEAP is a free RDBMS (Relational Database Management System) that has
been used as an educational tool in Universities around the world to aid
students as they learn database theory. It allows relational algebra
expressions to be entered directly into the system, and the results to
be queried. It supports relational closure, so complete expressions can
be deeply nested. Examples are included from popular database texts,
including C.J.Date's "An introduction to database systems".
<p>
LEAP is entirely free (it is distributed under the terms of the GNU
General Public License), and is very easy to install. All distributions
contain the full 'C' source code. Versions exist for all Unix
implementations, and Windoze 95/3.1/NT. Full documentation is included
in the distribution, and is available on the web. LEAP is in active
development (on a Linux 2.0 slackware system) by the author.
<p>
Full details, including links to the main ftp archives, are available on
the LEAP web page:
<p>
<A
HREF="http://www.dogbert.demon.co.uk/leap.html">http://www.dogbert.demon.co.uk/leap.html </A> <BR>
<A
HREF="http://www.brookes.ac.uk/~e0190404/leap.html">http://www.brookes.ac.uk/~e0190404/leap.html
</A> <BR>
<p>
Strictly speaking LEAP 1.1.9 is BETA software, but extensive testing has
shown no major problems.
<p>
For more information: <BR>
Richard Leyton, <A HREF="mailto:rleyton@acm.org">rleyton@acm.org</A>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
WMF - WebMailFolder 1.0.1 mail folder to html converter
</H3>
<p>
20 Feb 1998<BR>
This tool is for converting mails to html and can be used for
mailinglist archive.
<p>
It can be found on:
ftp://sunsite.unc.edu/incoming/Linux/
or ftp://sunsite.unc.edu/pub/Linux/Incoming/
should be moved to
ftp://sunsite.unc.edu/pub/Linux/apps/www/converters/
<p>
ftp://ftp.lugs.ch/incoming
should be moved to
ftp://ftp.lugs.ch/pub/linux/mail
<p>
For more details see the doc/ChangeLog or
Norbert Kuemin, Swisscom, <A
HREF="mailto:Norbert.Kuemin@gd2.swissptt.ch">Norbert.Kuemin@gd2.swissptt.ch
</A> <BR>
<A HREF="http://www.lugs.ch/LUGS_Members/norbert.kuemin/wmf.html">
http://www.lugs.ch/LUGS_Members/norbert.kuemin/wmf.html</A><BR>
<P> <hr> <P>
<!-- =================================================================== -->
<H3><IMG ALT=" " SRC="../gx/bolt.gif">
bash Book Released
</H3>
<P>
27 Feb 1998 <BR>
New Edition of the "Definitive Guide to bash" released--O'Reilly's
<I>Learning the bash Shell</I> By Cameron Newham & Bill Rosenblatt
now covers Version 2.0.
This second edition covers all of the features of bash Version 2.0,
while still applying to bash Version 1.x. New features include
one-dimensional arrays, parameter expansion, and more pattern-matching
operations. In addition, bash 2.0 is POSIX.2 conformant. This updated
edition covers new commands, security improvements, additions to
ReadLine, improved configuration and installation, and an additional
programming aid, the bash shell debugger.
<P>
For more information: <BR>
O'Reilly &amp; Associates, <A HREF="mailto:info@ora.com">info@ora.com</A>,
<A HREF="http://www.oreilly.com/">http://www.oreilly.com/</A>
<P> <hr> <P>
<!--================================================================-->
<center>Published in <i>Linux Gazette</i> Issue 26, March 1998</center>
<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; 1998 Specialized Systems Consultants, Inc. </H5>
<P>
<H4>"Linux Gazette...<I>making Linux just a little more fun!</I>"
</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:linux-questions-only@ssc.com">linux-questions-only@ssc.com</a><BR>
Starshine Technical Services, <A HREF="http://www.starshine.org/">
http://www.starshine.org/</A> </H4>
</center>
<p><hr><p>
<H3>Contents:</H3>
<ul>
<li><a HREF="./lg_answer26.html#telnet">Can't Telnet to Red Hat 5.0 Server</a>
<li><a HREF="./lg_answer26.html#luke">Use the Source, Luke!</a>
<li><a HREF="./lg_answer26.html#ifconfig">'ifconfig' to Troubleshoot Dropped Ethernet Packets?</a>
<li><a HREF="./lg_answer26.html#angel">Cthugha </a>
<li><a HREF="./lg_answer26.html#login">xdm Login doesn't!</a>
</ul>
<p><hr><p>
<!--================================================================-->
<a name="telnet"></a>
<h3><img align=bottom alt=" " src="../gx/ques.gif">
Can't Telnet to Red Hat 5.0 Server
</h3>
<P> <B>
From: Brad Lackey, <A HREF="mailto:lackeyb@holly.colostate.edu">
lackeyb@holly.colostate.edu</A>
</B> <P><B>
I am trying to set up a LINUX web server for Colorado State =
University - CIS Dept. I have Red Hat 5.0 Installed with user accounts =
set up but I cannot telnet to the machine. I get the login prompt, but =
none of the user accounts that I have created seem to work, including =
root. they all give me "Login incorrect". I was wondering how to fix =
this validation problem...<BR>
Thanks, Brad
</B> <P>
<img align=bottom alt=" " src="../gx/ans2.gif">
First I'll have to assume that you installed RH5 on
a fresh x86 machine with no previous OS, and that you've
just installed the package from a CD and have yet to
apply any upgrades or patches to it.
<P>
If that's the case -- fire up the old browser and go
to Red Hat's "Errata" pages at:
<P>
http://www.redhat.com/support/docs/rhl/rh50-errata-general.html
<P>
There are about 30 upgrade packages there -- including
fixes for the utils package (fixes 'vipw' command),
and glibc (the core c libraries which most of your
other programs depend upon through the magic of
shared libraries).
<P>
I don't see a specific entry for the problem that you're
describing -- and I haven't upgraded any systems to RH5
yet -- so I don't know if this problem is generic.
<P>
A quick search of Yahoo!/Alta Vista and DejaNews doesn't
show a match to exactly this problem either -- but it
does show that telnet to RH5 boxes is working for many
people. (Many of the problems reported have to do with
long delays, caused by the "double-reverse lookup" that
TCP Wrappers uses to prevent most varieties of spoofing).
So, given that the search string "+red +hat +5 +telnet
+login" didn't give us an easy answer we'll have to do
some troubleshooting.
<P>
Let's start with some questions:
<P>
Does your syslog (/var/log/messages or /var/log/security) tell
you anything?
<P>
Have you run pw5conv to enable shadow passwords?
<P>
If you run 'vipw' ('vi' the /etc/passwd file) do
the password hashes appear there?
<P>
Have you installed a different PAM (pluggable authentication
modules) or modified its configuration (any of the files
under /etc/pam.d/)?
<P>
I didn't see a new PAM RPM up at the site listed above
-- though things like the initscripts package and the
glibc package might help.
<P>
If these questions don't help you find the problem and
resolve it I'd suggest that you grab a Red Hat 4.2 or
a S.u.S.E., Debian or other distribution and install
that. If you use Red Hat 4.2 you'll want to fetch all
the upgrades for that -- and you might be able to install
specific RH5 rpms (including the glibc which *should*
co-exist cleanly with the libc 5.x that most (almost
all) Linux distributions prior to RH5 rely on).
<P>
As a support volunteer I find Red Hat's decision to
push the release of "Hurricane" out the door at the
end of last year to be abominable. I suggested to them
that they do a 4.5 first -- and wait until about March
of this year for a 5.0 (hoping that glibc would be
better understood, that PAM would move much closer to
1.0, and that the 2.2 kernel *might* ship by then).*
<P>
*** Please note: I don't have any "inside" hints as
to when any of these event will occur. I don't know
how long it will take to go from the 2.1.8x kernels
through the inevitable 2.1.99.x flurry and get to
2.2. I read the kernel mailing list and cross my fingers
like everyone else. Obviously Red Hat Inc (the company)
and Caldera, and Yggdrasil, and many other organizations
and individuals can help. If I were a programmer I might
be able to help more.
<P>
However, I was sure that 5.0 was too soon -- and the
34 Mb of upgrades and patches that were available as of
last November needed to be released on CD to save the
'net a bunch of bandwidth. (I occasionally cut these
and similar new stuff onto CD's using my ISDN line and
my CD-R and give them away. I'm hoping to give one or
two away at tonight's SVLUG (Silicon Valley Linux User's
Group) meeting where we'll be hearing from Bruce Perens
of the Debian project, and Eris S. Raymond, whose
paper on the "Crystal Cathedral" was cited as a key
part of Netscape's decision to release their sources)).
<P>
I'd like to see Red Hat adopt a subscription model, where
I can get monthly update of their "updates" and "contrib"
mirrors for about $10/month. (I suppose it doesn't *have*
to be Red Hat to do this, anyone with a CD-R and a reasonable
trickle feed from the 'net could do it. Though the
economies of scale don't work until we get a few hundred
subscribers).
<P>
Heck, if there's enough interest I'll do it.
<P>
In any event, I hope one of these methods works.
<P>
At the risk of starting serious flame wars and raising
questions about my "loyalty to the cause" (which cause
we're not sure) I'd also suggest that you look at the
OpenBSD (and FreeBSD and NetBSD) distributions if you
don't have a specific reason for picking Linux for
this application.
<P>
Linux is the most popular of the free Unix' -- but
it's not the only one -- and it's not necessarily the
best for all applications. OpenBSD, in particular, seems
to be very well suited to multi-user "student use" and
"computer lab" use. This is because Theo de Raadt and
his team have found and corrected a large number of
buffer overflows and other vulnerabilities in the sources
for FreeBSD and NetBSD (and probably in the sources of
many Linux utilities as well).
<P>
Obviously this depends quite a bit on your intended
applications. However, if I was setting up a general
use shell account system for a school lab, an ISP, or
a USENIX "terminal room" I'd probably suggest OpenBSD.
<P>
For personal workstations I think Linux holds the edge
in performance and applications availability.
<P>
--Jim
<p><hr><p>
<!--================================================================-->
<a name="luke"></a>
<h3><img align=bottom alt=" " src="../gx/ques.gif">
Use the Source, Luke!
</h3>
<P> <B>
From: SuatChoo Lua, <A HREF="mailto:suatchoo@yahoo.com">suatchoo@yahoo.com</A>
</B> <P><B>
Here there something that maybe you can answer me.
From where i can get the information about Linux
File system,memory managemant,and scheduling algorithm.
Thank you! <BR>
coco
</B> <P>
<img align=bottom alt=" " src="../gx/ans2.gif">
In many ways I'm not the best person to answer this
question. Remember that I am not a coder -- and I haven't
contributed any programming to the Linux kernel (which I'm
sure we all appreciate). However, I've read a bit of it
-- and will offer some opinions.
<P>
If you want deep information about -- technical
details -- about Linux filesystem, memory management,
and scheduling internals than the obvious thing to do
is to read the sources.
<P>
/usr/src/linux/kernel/sched.c is about 1700 lines long
(about 80 pages). There are about 30 .c files under
/usr/src/linux/fs (the filesystems directory) -- and
about 160 .c files under that whole tree. Linux supports
many different filesystems -- although the one that is
considered to be "native" to Linux is the ext2fs.
<P>
A variant of this filesystem has been adopted by the FSF
for their ongoing HURD project (which is a microkernel
OS for which rms and the Free Software Foundation developed
gcc, GNU emacs, and most of the applications and utilities
that make Linux possible).
<P>
The code for ext2fs is about 5000 lines. Probably the simplest
filesystem that ships with Linux is the Minix compatible one.
Minix is a simple microkernel operating system written by
Andrew S. Tanenbaum for inclusion with (and publication in)
his text book on "Operating Systems: Design and Implmentation."
That book is one of the seminal works on the topic -- and has
probably been studied by every major contributor to Linux.
<P>
The memory management code is in /usr/src/linux/mm. It
probably shows off the greatest innovations in the Linux
kernel. The aggressive strategies here allow a Linux kernel
to operate within a pretty modest footprint despite the
"freeping creaturism" that some of its detractors lament.
<P>
Where to begin:
<ul>
<li>I'd start by reading Tanenbaum's book (there's a
second edition where he's joined by Albert S.
Woodhull). Just read the first half to get all
the key concepts. The latter half of the book
are the sources for Minix; which don't relate to
Linux.
<li>I'd then pick up a copy of the <I>The Linux Kernel
Hacker's Guide</I> by Micheal K. Johnson (should be
at any good LDP -- Linux Documentation Project --
mirror site).
<li>Then grab a copy of <I>The Linux Kernel</I> by David
A. Rusling and <I>LINUX Kernel Internals</I> by Michael
Beck et al. (This last one is published by
Addison Wesley -- the others are available online
-- and published/printed in various editions of
_The_Linux_Bible_, _Dr._Linux_, etc).
</ul>
After you've read some of those the kernel sources will
hopefully make sense. Keep in mind that many of these things
are still changing in the form of patches and in the newer 2.1.x
kernels. For example there is a "evolution scheduler" which
allows you to experiment with different scheduling algorithms
for your Linux system. You can learn quite a bit about current
Linux limitations by perusing Kurt Huwig's collection of
"unofficial" Linux patches at http://linuxhq.sigkill.org/
or http://www.huwig.de if you'd like to read them in the
original German. These include several experimental
shedulers and memory management tweaks (like one that
search for duplicated pages and aliases them to one another
on the fly).
<P>
I hope you find all those interesting and informative.
<P>
--Jim
<p><hr><p>
<!--================================================================-->
<a name="ifconfig"></a>
<h3><img align=bottom alt=" " src="../gx/ques.gif">
'ifconfig' to Troubleshoot Dropped Ethernet Packets? Uh-Unhg!
</h3>
<P> <B>
From: Chris Oliphant, <A HREF="mailto:Chris.Oliphant@nextel.com">
Chris.Oliphant@nextel.com</A>
</B> <P><B>
I have a HP Vectra XM2 4/100i computer with an onboard PCnet/32
ethernet chip running Red Hat Linux 4.0, kernal version 2.0.18. I
currently am having problems communicating over the ethernet
connection for the last three days. I want to use IFCONFIG to
troubleshooting the problem, but don't understand how to use the
command's output. My problems are excessive receive packets being
dropped and excessive transmit errors. I am able to ping the onboard
chip, and the port connect is good with other systems connected to it.
But when I connect my Linux system to the port, I have problems.
Please advise. Thanks for any assistance you may provide.
--Chris Oliphant
</B> <P>
<img align=bottom alt=" " src="../gx/ans2.gif">
'ifconfig' is the "interface configuration" utility. It
isn't a troubleshooting tool. I'd usually 'ping', 'tcpdump'
and 'netcat'* or 'kermit'* for troubleshooting this sort of
problem.
<ul>
<li>netcat is at ftp.avian.org
(It is a little "swiss army knife" for TCP/UDP
-- providing a simple facility for scripted
TCP connections and transfers).
<li>kermit (C-Kermit) is at kermit.columbia.edu
(Aside from being a venerable file transfer
protocol and serial communications packages,
C-Kermit is also a telnet/rlogin client --
offering file transfers, scripting, debugging,
and log-to-file features over TCP connections).
</ul>
Based on your question here's a few standard support questions
to echo back:
<blockquote>
"for the last three days"? What happened then or
before then? Did the link work fine before then?
Did you upgrade your kernel? Change drivers? Add
a new video card? Did this kernel/driver/module
ever work acceptably with this ethernet card?
With this system's mixture of other components?
With a similar (so-called "identical") system?
</blockquote>
Excessive errors on an ethernet line suggests the following
sorts of problems:
<ol>
<li>high collision rates --
Are there other boxes on your LAN segment that might
be utilizing an excessive amount of the bandwidth?
How many systems are on this segment? What
applications are they running (particularly network
intensive)?
<P>
As an example if you put a few xterminals or diskless
workstation on a network and they fetch all of their
X resources, binaries and libraries over the wire
(rather than tftp to a local RAM disk for example) then
you can flood an unswitched ethernet segment in no time.
<li>hardware problems with your card or someone else's
(on the same network segment) --
<P>
It is possible that some ether card on your segment
is broken and "chattering" (generating spurious
signals which corrupt the data frames (network layer
"packets") from other cards. This is likely to
show symptoms across the entire segment (all the machines
will be affected). It is also possible that any
particular card is damaged. It is also possible for
the problem to be in a particular wire (are you using
10BaseT, coax/thin net, or (heaven forbid!) thicknet?),
or even a particular port on one of your hubs (repeater,
concentrator, whatever the "term du jour" for that
thingie-me-bob is). It could be as simple as "someone
kinked the wire by running it over with their chair
wheel."
<P>
A good way to test for this is to get an ethernet
"cross over" cable (sort of a "null modem" for 10BaseT)
and plug it between the problem system and a known
good one. This bypasses all the intervening components
to help isolate the problem.
<P>
(Basic troubleshooting 101: identify all components,
eliminate as many as possible for testing, continue
simplifying the configuration -- and possibly the tests
-- until something works, re-add components back until
failure. That isolates the problem.)
<P>
<li>bad driver or configuration --
If this has never worked under Linux (or under the
specific kernel your working with) you should boot
under some other OS and use whatever diagnostic
utilities HP provides. If those work and Linux
still fails it suggests a software configuration
or driver problem. If you had an older kernel that
did work without a problem, try booting with it
and running your tests -- it's always possible that
the card is broken in someway that only shows up
under conditions that don't occur from DOS or Win '95.
It's also possible that something in your kernel is
broken.
<P>
Naturally you'll also want to try a 2.0.33 or 2.0.34
kernel to see if that helps.
</ol>
As I've pointed out -- you need to do basic troubleshooting
in situations like this. You also want to ask yourself:
"Have I provided enough information for anyone (short of a
psychic) to answer this question?"
<P>
--Jim
<p><hr><p>
<!--================================================================-->
<a name="angel"></a>
<h3><img align=bottom alt=" " src="../gx/ques.gif">
Cthugha
</h3>
<P> <B>
From: kim angel, <A HREF="mailto:angelk@cadvision.com">
angelk@cadvision.com</A>
</B> <P><B>
Could you please tell me when Cthungha will be available for Win95?
Thanks!<BR>
Kim Angel
</B> <P>
<img align=bottom alt=" " src="../gx/ans2.gif">
Sorry. Can't be much help there.
I presume you mean Cthugha (no 'n') which would be
the audio/video amusement (turn your $3K multi-media
system into a $40 "discoteque" light).
<P> <B>
<img align=bottom alt=" " src="../gx/ques.gif">
Hmm....I detect a tad of dissatisfaction with the product!
</B> <P>
<img align=bottom alt=" " src="../gx/ans2.gif">
I've never run it. I have a lack of interest in the
class of software. I had to look it up in the LSM
(software map) to remember what it was -- since I
mis-remembered it as a "game").
<P>
I have no idea if or when it would be available for Win '95
-- or even why anyone would port it. However, I'd contact
the author/maintainer (should find his/her/their name(s)
in the man pages or docs).
<P> <B>
<img align=bottom alt=" " src="../gx/ques.gif">
What I am seeking is a program that is capable of applying digitized
animation choreographed to audio sequences. Could you help me with
this?
</B> <P>
<img align=bottom alt=" " src="../gx/ans2.gif">
I'm the "Linux Answer Guy" (or, to be more specific and
a little less pretentious, the "Linux Gazette Answer Guy").
<P>
It appears that Cthugha *is* just what you want -- for Linux.
I'm not the "Windows '95 Answer Guy." A role which I probably
would be wholly inadequate at since I don't run it on any of
my systems and I don't like what little of it I've had to run.
<P>
Despite this I can offer you a pretty simple piece of advice:
<blockquote>
Ask the author.
</blockquote>
Another possibility is that you could try the port yourself.
I'm not sure what the licensing of Cthugha and its sources is
-- but it's probably GPL. That license lets you port it to
any OS or platform you like -- or pay anyone else to perform
the port to your specs.
<P>
If you should find that the port to native Windows API's is
too difficult you could try DESQview/X (which offers X Windows
API's over DOS) or you could try OpenNT (from Softway Systems
at www.softway.com). OpenNT offers reasonably complete Unix
API's -- and some X Windows if I heard correctly -- and runs
under NT. I have also heard of several developers tools that
purport to compile Unix/X Windows code into native MS Windows
API's. However I don't have any experience with them, nor any
personal interest in them.
<P>
-- Jim
<p><hr><p>
<!--================================================================-->
<a name="login"></a>
<h3><img align=bottom alt=" " src="../gx/ques.gif">
xdm Login doesn't!
</h3>
<P> <B>
From: Cesar Augusto Kant Grossmann, <A HREF="mailto:ckant@fazenda.gov.br">
ckant@fazenda.gov.<BR></A>
</B> <P><B>
I run my Linux Box in the "graphics mode" (changing inittab accordling) =
bu I can't login as normal user. When I try to login as normal user, the =
screen flickers like a logout in the X, and the login screen comes back.
</B> <P>
<img align=bottom alt=" " src="../gx/ans2.gif">
This is also referred to as "using 'xdm'" (X Display Manager)
which provides a GUI login to X.
<P>
You don't mention what sort of system you have (which distribution
what architecture/platform, what packages you've installed or
updated, etc). You also don't mention whether you can login via
a text mode console (VC/VT) or via telnet or a serial line.
<P>
If you can, the problem is likely to be a mismatch between your
'xdm' binary and the authentication model/settings that you
have for your other 'login' modes.
<P>
This is one area where the FreeBSD crowd definitely had a
better model. Under Linux you can use the old-fashioned
(traditional -- and insecure) authentication mode where
the hashes of your passwords are stored in the /etc/passwd.
Alternatively you can install or enable some variation of the
"shadow" suite. This removes the password hashes from the
/etc/passwd file and stores them in a different file -- one which
is only accessible to privileged (SUID) programs -- and not
readable by normal users.
<P>
The purpose of all that is to make the system more resistant
to dictionary and cryptanalytic (brute force or otherwise)
attacks. In other words using the 'shadow' options is more
secure than allowing normal users to just snarf the hashes
up, and copy them to a machine running 'crack'.
<P>
The problem is that there are many programs that authenticate
users under Unix/Linux. In addition to login there's xdm,
ftpd, xlock, vlock, screen's lock feature, popd, imapd, the
passwd command etc. In FreeBSD they modified the libraries
-- and ensured that all the programs were linked against the
same shared library. This hides the details -- because the
library calls that "getpwent()" (get password file entries)
automatigically merge the passwd hash from the shadow file
(called /etc/pwdb.master? or somethine like that -- in
FreeBSD) if that file exists and is readable.
<P>
Thus unprivileged files on a shadow enabled get pw entries
with an "obscured" password field (usually just a "x")
while privileged (SUID) program get a merged one that's
suitable for comparison to a properly crypted/hashed
password as provided by an alleged user.
<P>
The other advantage to the FreeBSD method is that changing
the hashing algorithm (from the traditional 56-bit DES on
a string of zeros -- to a MD5 sum) is relatively easy --
only has to be supported in one place (the shared libraries)
and doesn't require that all the other programs be changed.
(Another feature of the FreeBSD password/account management
libraries is that they support dbm hashes of the account
names -- meaning that *huge* lists of accounts are possible
without suffering a "linear" increase in login/authentication
response times)
<P>
For now Linux has three different, and partially incompatible
account/authentication schemes:
<ul>
<li>Traditional /etc/passwd files
<li>Shadow suite (still with flat text files)
<li>PAM and libpwdb (dbm files and modular authentication
model).
</ul>
The frustrating thing is that these can all work together
do some degrees -- a pwdb system maintains a set of text
flatfiles that are sync'd to the dbm/hash tables (these hashes
are the indexed/search type -- as opposed to the cryptographic
variety that I referred to earlier -- like 56-DES and MD5).
<P>
Although Red Hat has shipped their last 2 or three releases
with PAM -- it isn't quite all there yet. The most recent
version of PAM is about 0.63 (beta). However -- if you installed
a recent Red Hat Linux (4.2 or 5.0 with patches)
you should be able to use its xdm and all of their stock utils
without trouble.
<P>
If you compiled your own 'xdm' or fetched it from somewhere
you should consider recompiling it -- but looking for
options that relate to "shadow" support.
<P> <B>
<img align=bottom alt=" " src="../gx/ques.gif">
What seems to happen? Where I can find more informations about these? A
FAQ or something like...
</B> <P>
<img align=bottom alt=" " src="../gx/ans2.gif">
I'd start by reading the Shadow HOWTO. I'd also suggest a
web search on PAM (pluggable authentication modules):
Here's some URL's I have for them:
<ul>
<li>Andrew Morgan's Page:
http://www.kernel.org/pub/linux/libs/pam/
<li>The Linux-PAM System Administrators' Guide:
http://www.math.muni.cz/linux/Linux-PAM/html/pam.html
<li>PAM - Pluggable Authentication:
http://www.redhat.com/linux-info/pam/
<li>PAM specs -- OSF RFC 86.0:
http://sysadm.sorosis.ro/devel/pam/rfc86.0.txt
</ul>
It's a good idea to read about PAM since several other
Unix flavors are also moving towards it (currently appearing
in Solaris and HP-UX, at least).
<P> <B>
<img align=bottom alt=" " src="../gx/ques.gif">
Sorry for my bad English, but I think it's better than your
Portuguese...
</B> <P>
<img align=bottom alt=" " src="../gx/ans2.gif">
Undoubtedly your English is better than my Portugese --
or even my French (I've never studied the former and only
had a couple of high school years of the latter).
--Jim
<!--================================================================-->
<P> <hr> <P>
<center><H5>Copyright &copy; 1998, James T. Dennis <BR>
Published in <I>Linux Gazette</I> Issue 26 March 1998</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><H2>Clueless at the Prompt</H2>
<H4>By Mike List,
<a href="mailto:troll@net-link.net">troll@net-link.net</a></H4>
</center>
<P> <HR> <P>
<center><IMG ALIGN=MIDDLE SRC = "../gx/list/gnub.jpg" ></center><p>
<h4>Welcome to installment 6 of Clueless at the Prompt,</h4>
<p>
Here's this month's account of the triumphs, trials and
tribulations that I caused myself or encountered since the last
time, and a couple tips that may come in handy and increase your
understanding of linux.
<hr><p><h4>
*Splitvt and Screen:</h4> Last month, I suggested splitvt as a substitute
for virtual consoles when using a serial terminal. I still recommend
splitvt since you can work in two separate windows that are in sight of
each other- cut and paste with gpm is a snap for scavenging previously
written scripts or....
But several people wrote to tell me about screen, which is an even better
substitute for virtual consoles when using that dumb terminal. I'm still
working on making screen work fluidly, Alt-F* took a little
getting used to at first. Instead of the A-F* combination you use the
C-a* keys to open a new window. There are some other features that I have
only read about, the only difference between screen and virtual consoles
is that each new screen is already logged on.
<p>
Like I said, I'm not familiar with all of screen's features, but to use
it, basically you type:
<pre>
screen progname
</pre>
and your screen session is started in VT0.
To add more VTs you can use:
<pre>
Ctrl-a c
</pre>
and to change from one screen to another:
<pre>
Ctrl-a 0-9
</pre>
and you can change from screen to screen, depending on how many you have
opened. Note that the screens are numbered 0-9 rather than 1-10,
the only clumsy feature of this program, IMHO.
<hr><p><h4>
*Back to basics:</h4> Some friends of mine, the nefarious UGD folks
have a page <a href="http://www.geocities.com/SiliconValley/Pines/1703/docs/dog/">
"User Guide Dog"</a>which details many, if not
most of the usual commands that a new user might find useful but not
clearly documented. I don't have to tell you that man pages can be pretty
hostile to a gnubee (ever wonder what that picture was?), but if you
check them out after using the programs to do the things you most commonly
need to do, you will most likely achieve enlightenment - the information
is suddenly much more clear. The UGD Project is shaping up as a good
vehicle for this journey, if you can take the ride. Bring along your sense
of humor, one of the guys is a Canadian from out on the tundra ; ).
<hr><p><h4>
*Some stuff you may not hear anywhere else (so basic they forgot
to tell you):</h4>
<ul>Here's some stuff you probably already know
about, if you've been into Linux (or other unices)for a while.
<li><h4>Filename Completion</h4>: If you aren't an enthusiastic
typist, you'll find this of value. Just type enough of the filename
to make it unique, then hit
<pre>tab</pre>
it will complete the filename so you can get on with your life
and file manipulation.Play with this feature, if you haven't
typed enough of the name to be unique, it will sit and stare at
you, try another character or two.Likewise, if you specified the
wrong directory,you'll get nada.
<li><h4>Quick cd</h4>: Another keystroke saving apparatus
is:
<pre>..</pre>
and its close relative
<pre>.</pre>
The details for
a quick cd areas follows: as you may be already aware, the dots
represent your current directory(single dot) and parent directory
(double dot).By CDing to
<pre>..</pre>
you will be magically transported to the parent directory, ie
from /usr/bin to /usr.You can use:
<pre>cd -</pre>
to return to the previous directory,
and to go up two or more levels:
<pre>../../and so on</pre>
will work. The single dot is not as useful in terms of cd, but it
does have its use. If you are in a directory that's not in your
path, or dont have
<pre>.</pre>
in your path statement, you must
give a path to run an executable file. This is easily accomplished
by typing:
<pre>./execuname</pre>
which will give the relative pathname, allowing it to be found and
run.
There are a few good reasons why using the single
dot in your path statement isn't a good idea, suffice to say, if
you'd like more info on that subject, you should read up on system
security.
<li><h4>GPM</h4>: This has been so basic to my linux experience
that I would be crippled without it, in fact once when I flubbed
an installation and didn't have it running, it became my first
priority to correct that little oversight. The mere fact that the
non unix OS seem not to have this is reason to upgrade to Linux,
although I found a dos program that allows a similar use of the
mouse on simtelnet. In a related matter, if you dual boot(most
home boxes, I'd imagine)you might find yourself using
<pre>ls -aF</pre>
when you actually meant to type
<pre>dir</pre>
or
<pre>cp</pre>
when what you wanted was
<pre>copy</pre>
you can create batch files(like shell scripts) named for your
favorite unix commands, using your favorite switches. Not as
cool as dosemu or just plain staying in Linux, but ya gotta do
what ya gotta do.
</ul>
<hr><p><h4>
*Errata:</h4> No I don't really do "make dev" when I make a kernel
(maybe I could blame it on my keyboard)make dep is what I meant.
<hr><p>
If you have a subject that you would like to see covered or have
any corrections, comments or flames let me know, and I'll look
into the matter.
<a href="mailto:troll@net-link.net">troll@net-link.net</a><p>
<b>See you next month!</b></center>
<!--===================================================================-->
<P> <hr> <P>
<center><H5>Copyright &copy; 1998, Mike List<BR>
Published in Issue 26 of <i>Linux Gazette</i>, March 1998</H5></center>
<!--===================================================================-->
<P> <hr> <P>
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<H4>
"Linux Gazette...<I>making Linux just a little more fun!</I>"
</H4>
<P> <HR> <P>
<!--===================================================================-->
<center>
<h1>EMACSulation</h1>
<h4>by
<a href="mailto:emarsden@mail.dotcom.fr">Eric Marsden</a>
</h4>
</center>
<P> <HR> <P>
<blockquote><small>
This column is devoted to making the best use of Emacs, text editor
extraordinaire. Each issue I plan to present an Emacs extension
which can improve your productivity, make the sun shine more brightly
and the grass greener.
</small></blockquote>
<h2>Internet-ready!</h2>
<p> You've probably heard the hype about ``Internet-ready'' operating
systems where you can access the Internet with a click of your mouse.
Well, users of the customizable <a
href="http://www.jimpick.com/gnome/ui-proposal/">Emacs user
interface</a> have had the Net only a keypress away since as early as
1989!
<p> Emacs has built-in networking capability, which it uses for connecting
to news or SMTP servers and for web browsing. To illustrate its use,
here is a bit of code which opens a TCP connection to port 13 of your
local machine to request the current time&nbsp;:
<pre>
;; usage: M-x display-date
(defun display-date ()
(interactive)
(let ((stream (open-network-stream "DAYTIME" nil "localhost" "daytime")))
(set-process-filter stream 'my-process-filter))
(defun my-process-filter (proc string)
(message "Current date is %s" (substring string 0 -1)))
</pre>
<p> This code --which assumes you're running inetd-- should display
something like the format of <code>date</code> in the minibuffer. The
rich set of primitives and the integrated error management provided by
Emacs make it easy to program useful utilities; consider how many
lines of code would have been required to provide the equivalent
functionality in C.
<h3>Ange-ftp</h3>
<p> <b>Ange-ftp</b> is a package by <a
href="http://hplbwww.hpl.hp.com/people/ange/">Andy Norman</a> which
allows Emacs to see the entire Internet as a virtual filesystem. It
adds remote editing capability by mapping requests for remote files to
FTP commands. For example, if you ask Emacs to open a file named
<pre>
/marsden@ondine.cict.fr:~/.emacs
</pre>
<p> then ange-ftp will spawn an FTP process, connect to the host
<tt>salines.cict.fr</tt> as user <tt>marsden</tt>, CWD to my home
directory, GET my Emacs initialization file and display the file as if
it were on your local filesystem. If ange-ftp needs a password it will
read one from the minibuffer. If you make changes to the file and save
it, it will be PUT back to the server for you. You can even copy files
from one remote machine to another by typing <code>M-x copy-file RET
/user1@host1:/path/to/file1 RET /user2@host2:/path/file2</code>&nbsp;;
ange-ftp looks after opening two ftp connections for you.
<p> Ange-ftp comes pre-installed with Emacs (XEmacs features <b>efs</b>, a
complete rewrite by the same author). The only customization you might
need to make is to configure a gateway, if you don't have direct
Internet access. You can use <tt>~/.netrc</tt> to configure default
logins for oft used hosts in the traditional way (and even passwords if
you're foolhardy).
<p> Perhaps the most elegant feature of ange-ftp is its seamless
integration with Emacs; the only visible change it introduces is the
extended filename syntax. Filename completion (by pressing <tt>TAB</tt>
in the minibuffer) is available on remote hosts in the same way as on
your local machine. Ange-ftp works well with Dired, the directory
editor, allowing you to browse though distant machines, operate on
several remote files at once, etc. It also works with <a
href="http://www.cl.cam.ac.uk/texinfodoc/emacs_14.html#SEC71">bookmarks</a>,
so you can memorize an interesting spot on your favorite ftp server,
and jump back to the same spot next week with ease. Take a typical
usage: ask Emacs to open the following directory (with <code>C-x
C-f</code> or from the Files menubar)&nbsp;:
<pre>
/anonymous@ftp.kernel.org:/pub/linux/kernel/
</pre>
<p> You will be presented with a directory listing many different releases
of Linux kernels (if you have a line like <code>default login anonymous
password user@site</code> in <tt>~/.netrc</tt> then ange-ftp can infer
the <tt>anonymous@</tt> for you automatically). Type <code>C-x r
m</code> to bookmark the location. There's more on bookmarks in Jesper
Pedersen's <a
href="http://www.linuxgazette.com/issue01to08/emacs_mar96.html">article</a>
in issue 7 of the <i>Linux Gazette</i>.
<h3>Web browsing</h3>
<p> <a href="http://www.cs.indiana.edu/elisp/w3/docs.html">Emacs-w3</a>
(also referred to by some as <i>Gnuscape</i>) is a web browser written
by William Perry in Emacs Lisp. It is fairly sophisticated in certain
respects, having been the first production browser to support cascading
style sheets. It understands tables, and can display images inline
under <a href="http://www.XEmacs.org/">XEmacs</a>, or by invoking
external viewers when hosted by GNU Emacs. Its author notes that
Emacs-w3 is yet another reason never to leave the comfort of the One
True Editor, but to me it serves more as a reminder of the deficiencies
of Emacs Lisp : it is slow, and has a tendency to block while waiting
on a slow link (unfortunately Emacs is not multi-threaded, though you
can set the variable <tt>url-be-asynchronous</tt> to t to reduce this
annoyance). If you want to try it out get the latest version from the
<a href="ftp://ftp.cs.indiana.edu/pub/elisp/w3/.betas/">betas
directory</a>, which has many improvements over the version distributed
on most Linux CDROMs.
<p> <b>browse-url</b> is an nifty Emacs extension which can dispatch
references to URLs to Mozilla or to Emacs-w3. It does this by using
Netscape's <a
href="http://home.netscape.com/newsref/std/x-remote.html">remote
invocation protocol</a>, which as a side note even works when you're
running the browser on a distant machine (the implementation uses the
X11 inter-application communication protocol). Emacs features its own
remote control mechanism which lets you send commands to a running Emacs
(even on another machine), called gnuserv/emacsclient, which I might
talk about another time.
<p> Recent versions of Emacs are set up to use browse-url in mail and news
reading modes. URLs should be highlighted when you pass the mouse over
them, and you can click on them with the middle mouse button to invoke
your favorite browser. Here's how you can set up browse-url to use
Mozilla when you're running X11 and Emacs-w3 otherwise&nbsp;:
<pre>
(if (eq window-system 'x)
(setq browse-url-browser-function 'browse-url-netscape
browse-url-new-window-p t)
(setq browse-url-browser-function 'browse-url-w3))
</pre>
<p> Another more indirect use of browse-url is <a
href="http://nwv.www.media.mit.edu/people/nwv/projects/webjump/">WebJump</a>
by Neil W. Van Dyke. This Emacs plugin provides a programmable hotlist
of interesting web sites with which to feed your browser. Perhaps its
most interesting feature is the ability to send a query to Internet
search engines such as <a
href="http://www.altavista.digital.com/">AltaVista</a> and <a
href="http://www.yahoo.com/">Yahoo!</a> without having to load the
first page of ads, but it also includes features for dispatching
searches to FAQ and RFC archives, to the <a
href="http://www.m-w.com/dictionary.htm">online Webster</a> or <a
href="http://www.thesaurus.com/">Thesaurus</a>, or to bring up an
appropriate page of the Java API. Naturally (this is Emacs) you can
extend it to include your own favorite sites. You might find yourself
using it more than your browser's bookmarks.
<h3>Files at your Fingertips</h3>
<p> <b>ffap</b> is a powerful package which extends the
<code>find-file</code> command (the one which prompts for a file name
in the minibuffer, normally bound to <code>C-x C-f</code>). It searches
the text around the cursor position for something which might represent
a filename -- a file in the current directory, a C #included file, a
newsgroup reference, an ange-ftp style reference to a file on a remote
machine or an URL -- and prompts you either to open that file, or to
send the URL to a browser (via browse-url). Once experiencing this you
quickly get sick of typing filenames into the minibuffer, and may find
yourself inserting ``hyperlinks'' in strategic places in your files to
save typing. ffap is distributed with both Emacs and XEmacs; I bind it
to the F3 key as follows&nbsp;:
<pre>
(autoload 'find-file-at-point "ffap" nil t)
(define-key global-map [(f3)] 'find-file-at-point)
</pre>
<p> or if you prefer you can simply override the traditional
<tt>find-file</tt> by saying
<pre>
(autoload 'find-file-at-point "ffap" nil t)
(define-key global-map [(control x) (control f)] 'find-file-at-point)
</pre>
<p> ffap is pretty good at determining interesting filenames; it even knows
how to recognize RFC names, and from which server they may be obtained.
It goes to the trouble of pinging remote machines to determine whether
they are alive, and can naturally be extended to recognize personal
types of filename references. To conclude on filename shortcuts, you
might enjoy Noah Friedman's <a
href="http://www.splode.com/users/friedman/software/emacs-lisp/index.html#fff">fff</a>
(Fast File Finder) which helps you find files hidden somewhere deep in
inode-space by querying your <tt>locate</tt> database (part of the GNU
findutils).
<h2>Feedback</h2>
<p> Several people wrote to me with comments on last month's article on
<b>jka-compr</b>. <a href="mailto:cbbrowne@hex.net">Chistopher B.
Browne</a> told me he prefers <a
href="ftp://archive.cis.ohio-state.edu/pub/gnu/emacs/elisp-archive/misc/crypt++.el.Z">crypt++</a>,
which provides on-the-fly decryption and encryption as well as
automatic compression and decompression. Whereas jka-compr trusts the
filename extension, crypt++ reads the first few bytes of the file to
determine its type. The package also has functions for dealing with
DOS-style linefeeds which you might find useful if you have to exchange
files with other operating systems, although you could just as well say
<code>(standard-display-ascii 13 "")</code>, which simply hides those
<tt>^M</tt> characters. Crypt++ is not a standard part of Emacs (it's
not included in the GNU Emacs distribution, though it is bundled with
XEmacs). I haven't tested its cryptographic capabilities, because
<blockquote>
<tt>&lt;POLITICS&gt;</tt> <br>
As a French citizen I am <a
href="http://cwis.kub.nl/~frw/people/koops/cls2.htm#fr">prohibited</a>
from using any form of encryption. In France encryption requires
authorization from the <a
href="http://www.elysee.fr/pdt/pdt.htm">President</a>, which is
accorded only to large military companies and to financial institutions
(and then only if the keys are held in escrow). These laws are <a
href="http://www.uwsg.indiana.edu/hypermail/linux/kernel/9611/0396.html">one
of the reasons</a> holding back the incorporation of kernel-level
support for encryption in Linux. Before accusing France of being
backward, please consider the fact that countries such as Iran, China
and Russia impose similar restrictions on the freedom of their
citizens.
<br> <tt>&lt;/POLITICS&gt;</tt>
</blockquote>
<p> If you're using the latest version of XEmacs (20.3 stable as of this
writing), the suggestion I make last month for enabling
<b>jka-compr</b> won't work. The XEmacs maintainers have decided that
the behaviour of your editor shouldn't be modified by loading an
extension module, but by calling an appropriate initialization
function. The correct way of enabling jka-compr is to say
<code>(toggle-auto-compression 1 t)</code>. Sorry 'bout that, folks.
<h2>Next time ...</h2>
<p> In the next issue I'll review ediff, a powerful interface to diff
and patch. Don't hesitate to contact me at
<tt>&lt;emarsden@mail.dotcom.fr&gt;</tt> with comments, corrections or
suggestions (what's <em>your</em> favorite couldn't-do-without Emacs
extension package?). <code>C-u 1000 M-x hail-emacs</code> !
<p> <b>PS</b> : Emacs isn't in any way limited to Linux, since
implementations exist for many other operating systems. However, as one
of the leading bits of <a
href="http://earthspace.net/~esr/open-source.html">open-source</a>
software, one of the most powerful, complex and customizable, I feel it
has its place in the <i>Linux Gazette</i>.
<!--===================================================================-->
<P> <hr> <P>
<center><h5>Copyright &copy; 1998, Eric Marsden<br>
Published in Issue 26 of <i>Linux Gazette</i>, March 1998</H5></center>
<!--===================================================================-->
<P> <hr> <P>
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<H4>
"Linux Gazette...<I>making Linux just a little more fun!</I>"
</H4>
<P> <HR> <P>
<!--===================================================================-->
&nbsp;<!-- =============================================================
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.
============================================================= !--><!-- The Button box as a client side imagemap -->&nbsp;<MAP NAME="nav-main"><AREA SHAPE="rect" HREF="#mews" coords="20,18 185,40"><AREA SHAPE="rect" HREF="#webwonderings" coords="10,60 185,83"><AREA SHAPE="rect" HREF="#musings" coords="90,102 185,130"><AREA SHAPE="rect" HREF="#resources" coords="70,152 185,180"></MAP>
<TABLE BORDER=0 COLS=2 WIDTH="100%" >
<TR>
<TD><IMG SRC="../gx/hammel/gm3.gif" ALT="Welcome to the Graphics Muse" NOSAVE HEIGHT=216 WIDTH=441 ALIGN=LEFT></TD>
<TD VALIGN=BOTTOM>
<CENTER><FONT SIZE=-1>Set your browser as wide as you'd like now.&nbsp;
I've fixed the Muse to expand to fill the aviailable space!</FONT></CENTER>
<CENTER><FONT SIZE=-2>&copy; 1998 by <A HREF="mailto:mjhammel@csn.net">mjh</A>&nbsp;</FONT></CENTER>
</TD>
</TR>
</TABLE>
&nbsp;
<HR WIDTH="100%">
<TABLE BORDER=0 COLS=2 WIDTH="100%" >
<TR>
<TD WIDTH="185"><IMG SRC="../gx/hammel/muse-image-map.gif" BORDER=0 ALT="Button Bar" USEMAP="#nav-main" HEIGHT=200 WIDTH=185 ALIGN=LEFT></TD>
<TD VALIGN=TOP><B><FONT SIZE=+1>muse:</FONT></B>&nbsp;
<OL>
<LI>
<I>v;</I> to become absorbed in thought&nbsp;</LI>
<LI>
<I>n;</I> [ fr. Any of the nine sister goddesses of learning and the arts
in Greek Mythology ]: a source of inspiration&nbsp;</LI>
</OL>
&nbsp;<IMG SRC="../gx/hammel/w.gif" ALT="W" HEIGHT=28 WIDTH=36 ALIGN=BOTTOM>elcome
to the Graphics Muse! Why a "muse"? Well, except for the sisters aspect,
the above definitions are pretty much the way I'd describe my own interest
in computer graphics: it keeps me deep in thought and it is a daily source
of inspiration.&nbsp;
<CENTER><FONT SIZE=-1>[<A HREF="#mews">Graphics Mews</A>][<A HREF="#webwonderings">WebWonderings</A>][<A HREF="#musings">Musings</A>]
[<A HREF="#resources">Resources</A>]</FONT></CENTER>
</TD>
</TR>
</TABLE>
&nbsp;
<BR><IMG SRC="../gx/hammel/t.gif" ALT="T" HEIGHT=28 WIDTH=26 ALIGN=LEFT>his column
is dedicated to the use, creation, distribution, and discussion of computer
graphics tools for Linux systems.
<BR>&nbsp;
<BR>Not much to say this month.&nbsp; I've been very busy working on some
things for Linux Journal and a few other projects.&nbsp; I&nbsp;did manager
to get the reviews done that I had promised last month.&nbsp; Well, 2 out
of 3 of them.&nbsp; Thats better than I usually do.
<P>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; In this months column I'll be covering
the following:
<UL>
<LI>
XeoMenu, a Java based menuing program</LI>
<LI>
an update on X server support for 3D cards and the X Input Extension</LI>
<LI>
VRWave, a VRML browser for Linux</LI>
</UL>
<A NAME="mews"></A>
<BR>&nbsp;
<TABLE BORDER=0 COLS=1 WIDTH="100%" >
<TR>
<TD><IMG SRC="../gx/hammel/mews.gif" ALT="Graphics Mews" HEIGHT=53 WIDTH=242 ALIGN=LEFT></TD>
</TR>
</TABLE>
&nbsp;&nbsp;&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>&nbsp;
<TABLE BORDER=0 COLS=3 WIDTH="100%" >
<TR>
<TD COLSPAN="3" WIDTH="100%" BGCOLOR="#000000"><IMG SRC="../gx/hammel/cleardot.gif" ALT="indent" HSPACE=30 VSPACE=2 HEIGHT=1 WIDTH=1 ALIGN=LEFT></TD>
<TD></TD>
</TR>
<TR>
<TD WIDTH="50%">
<H2>
XFPovray 1.3</H2>
<A HREF="mailto:mallozzir@cspar.uah.edu">Robert Mallozzi </A>announces
a new version (1.3) of his XForms interface to the ray tracer POV-Ray.&nbsp;
If you have ever used POV-Ray from the command line, you might find this
program useful.&nbsp; Check&nbsp;
<P>&nbsp;&nbsp; <A HREF="http://cspar.uah.edu/~mallozzir/">http://cspar.uah.edu/~mallozzir/</A>&nbsp;
<P>Source code is available in tgz, bzip2, and rpm formats.&nbsp;
<P>Robert S. Mallozzi&nbsp;
<BR>University of Alabama&nbsp;
<BR>http://cspar.uah.edu/~mallozzir/</TD>
<TD ROWSPAN="3" WIDTH="2" BGCOLOR="#000000"><IMG SRC="../gx/hammel/cleardot.gif" ALT="indent" HSPACE=1 HEIGHT=1 WIDTH=1></TD>
<TD WIDTH="49%">
<H2>
XMRM 2.0 (Alpha release)</H2>
The Institute of Computer Graphics at Vienna University of Technology,
Austria, announce the release of XMRM 2.0alpha&nbsp;
<P>XMRM (multi resolution morphing for X) is an image morphing program
written for XWindows. A special feature of this program, which is not found
in other morphing packages, is the ability to control the morphing speed
of details in relation to the morphing speed of big features.&nbsp;
<P>Check out the XMRM homepage:&nbsp;
<BR><A HREF="http://www.cg.tuwien.ac.at/research/ca/mrm/">http://www.cg.tuwien.ac.at/research/ca/mrm/</A>&nbsp;
<P>For a few animated GIFs visit the Online manual:&nbsp;
<BR><A HREF="http://www.cg.tuwien.ac.at/~xmrm/">http://www.cg.tuwien.ac.at/~xmrm/</A>&nbsp;
<P>For download got to:&nbsp;
<BR><A HREF="ftp://ftp.cg.tuwien.ac.at/pub/linux/xmrm/">ftp://ftp.cg.tuwien.ac.at/pub/linux/xmrm/</A>&nbsp;
<P>Greetings, The XMRM-Team &lt;<A HREF="mailto:xmrm@cg.tuwien.ac.at">xmrm@cg.tuwien.ac.at</A>>&nbsp;
<BR>&nbsp;</TD>
</TR>
<TR>
<TD BGCOLOR="#000000"><IMG SRC="../gx/hammel/cleardot.gif" HSPACE=1 HEIGHT=1 WIDTH=1></TD>
<TD BGCOLOR="#000000"><IMG SRC="../gx/hammel/cleardot.gif" HSPACE=1 HEIGHT=1 WIDTH=1></TD>
</TR>
<TR>
<TD>
<H2>
FREETYPE 1.0 The FREE TrueType Font Engine</H2>
Copyright (C) 1996-1998 The FreeType Development Team&nbsp;
<P>The FreeType engine is a free and portable TrueType font rendering engine,
available in&nbsp; ANSI C and Pascal source&nbsp; code.&nbsp; It has been
developed to&nbsp; provide TrueType support&nbsp; to a great variety&nbsp;
of platforms and environments.&nbsp;
<BR>&nbsp;
<BR>Notice that&nbsp; FreeType is a <I>library</I>.&nbsp;&nbsp; It is not
a font server for your&nbsp; preferred environment, even though it&nbsp;
has been designed to&nbsp; be the&nbsp; basis of&nbsp; many&nbsp; high-level
libraries,&nbsp; tools and font servers.&nbsp;
<P>It's&nbsp; a clean-room&nbsp; implementation that&nbsp; is not&nbsp;
derived&nbsp; from the original&nbsp; TrueType engine developed&nbsp; by
Apple&nbsp; and Microsoft,&nbsp; though it matches it&nbsp; regarding rendering&nbsp;
quality.&nbsp; To our&nbsp; knowledge, it's the only royalty-free complete
TrueType engine available.&nbsp;
<P>For more information, please visit the Freetype web site at:&nbsp;
<BR><A HREF="http://www.physiol.med.tu-muenchen.de/~robert/freetype.html">http://www.physiol.med.tu-muenchen.de&nbsp;</A>&nbsp;
<BR><A HREF="http://www.physiol.med.tu-muenchen.de/~robert/freetype.html">/~robert/freetype.html</A>&nbsp;
<BR>&nbsp;</TD>
<TD>Thats its.&nbsp; Not much in the way of announcments this month.&nbsp;
I had a few more, but lost them pasting them into my XPostitPlus program.&nbsp;
Thats the first time its crashed in that manner - where I lost the data.&nbsp;
Bummer.</TD>
</TR>
<TR>
<TD COLSPAN="3" WIDTH="100%" BGCOLOR="#000000"><IMG SRC="../gx/hammel/cleardot.gif" HSPACE=1 HEIGHT=1 WIDTH=1></TD>
</TR>
</TABLE>
&nbsp;<!--
-- Did You Know Section
-->
<H4>
Did You Know?</H4>
...there is a OpenGL widget for GTK?&nbsp; Take a look at <A HREF="ftp://ftp.gimp.org/pub/gtk/contrib/glgtk-demo.971104.tgz">ftp://ftp.gimp.org/pub/gtk/contrib/glgtk-demo.971104.tgz.</A>
<BR><!--
-- Q and A Section
-->
<H4>
<B><FONT SIZE=+0>Q and A</FONT></B></H4>
<I>Q:</I>&nbsp;&nbsp; <I>How do you use anti-aliasing with POV-Ray?&nbsp;
Do higher values cause more anti-aliasing?</I>
<P>A:&nbsp;&nbsp; Ron Parker responded on the IRTC-L discussion list:&nbsp;
Whenever POV-Ray detects a sufficient change, the <I>threshold</I>, in
colour from one pixel to it's neighbour, it will calculate the in-between
color pixels by shooting multiple rays into the scene, rather than just
one, to determine the colour.&nbsp; The higher the "+A" number is (from
0 to 1), the more rays will be shot into the scene, and the smaller a difference
in colour from one pixel to the next will be needed to cause the anti-aliasing
to be brought into effect.&nbsp; Anti-aliasing is triggered when the threshold
between two pixels is reached. The number of rays is controlled by +R,
and the "spread" is controlled by +J.&nbsp; Setting +A0.1 will trigger
on smaller color differences than +A0.3, so it actually anti-aliases more
than higher values of +A.&nbsp; All this is the description for +AM=1.&nbsp;
Adaptive supersampling (+AM=2) works somewhat differently.
<P>For more information, see section 6.2.5.4 of the POV documentation.
<P>Ron Parker * <A HREF="mailto:parkerr@mail.fwi.com">parkerr@mail.fwi.com</A>
* <A HREF="http://www2.fwi.com/~parkerr">http://www2.fwi.com/~parkerr</A>
<P><I>Q: I took an image to a printer today who requested that I bring
back the image when I have increased the resolution from 72 pixels/inch
to 300 pixels /inch. I cant locate how to do this with the GIMP. Any pointers?</I>
<P>A:&nbsp;&nbsp; You can scale the image, but that will decrease the quality
of the image. The best way to deal with images you plan to print is to
plan to <I>create</I> them using the correct resolution.&nbsp; For example,
if you want an 8.5" by 11" image at 300pixels/inch:
<UL><B><FONT SIZE=-1>width: 8.5*300 = 2550 pixels</FONT></B>
<BR><B><FONT SIZE=-1>height: 11*300 = 3300 pixels</FONT></B></UL>
So you need to start with an image window that is 2550x3300 and work from
there.&nbsp; Keep in mind - doing this sort of image manipulation (with
such large image sizes) is better suited to:
<OL>
<LI>
faster CPU's.</LI>
<LI>
tons of memory</LI>
<LI>
lots of disk space</LI>
</OL>
As to "can I convert from 72 to 300 pixels from my original image": yes,
use the scale option (image->scale) and set the correct size.&nbsp; But
remember - scaling up will reduce image quality, especially going from
72dpi to 300dpi.
<BR>&nbsp;
<TABLE BORDER=0 COLS=1 WIDTH="100%" BGCOLOR="#000000" NOSAVE >
<TR>
<TD><IMG SRC="../gx/hammel/cleardot.gif" HEIGHT=3 WIDTH=1></TD>
</TR>
</TABLE>
<H2>
Reader Mail</H2>
An unnamed reader sent the following information:
<UL>I've recently written 3 Perl scripts which help to distribute the task
of rendering with povray between several CPU's.&nbsp; One script is for
SMP (multiple processor) machines.&nbsp; It will break an image into halves
and start a separate process for each.&nbsp; This utilizes both CPU's in
a dual processor machine, and nearly halves the rendering time.&nbsp; The
other two scripts work together to utilize multiple machines on a network.&nbsp;
The server script tells each client script how much of an image to render
(also sending the .pov file and any necessary files to each client).
<P>These scripts were created using Perl 5.004, Linux 2.0.32, and POVRay
3.0. I'd be honored if you would like to include a link from your excellent
graphics site to my page at <A HREF="http://www.frozenwave.com/~hixson/projects.html">http://www.frozenwave.com/~hixson/projects.html</A>.</UL>
<FONT COLOR="#993300"><B><I>'Muse</I></B>:</FONT>&nbsp; I really need to
update the LGH and UGU pages.&nbsp; Anyway, if any of my readers tries
these scripts, let me know what you think of them.&nbsp; I don't have any
multiprocessor boxes, although I do have a network.&nbsp; I just don't
have time right now to experiment with these scripts.
<P><A HREF="mailto:slogan@cts.com">Syd Logan</A>, Senior Software Engineer
@ NetManage, Inc., writes:
<UL>I was perusing an old copy of <A HREF="http://www.linuxjournal.com">The
Linux Journal</A> in preparation to do an article or two for them on the
X Image Extension when I came across your article in the November 1996
issue. This isn't so much about the article, but I just thought I'd drop
you a line to make you aware of my home page which is devoted to XIE at
<A HREF="http://www.users/cts.com/crash/s/slogan">http://www.users/cts.com/crash/s/slogan.</A>
Feel free to point any queries you may hear about or receive regarding
XIE or XIElib to my home page, or to me directly at <A HREF="mailto:slogan@cts.com">slogan@cts.com</A>.</UL>
'<B><I><FONT COLOR="#993300">Muse:&nbsp;</FONT></I></B> Thanks for the
note.&nbsp; While working for Xi Graphics I had read the XIE specification
and wondered why it hadn't been used much.&nbsp; Perhaps its like X Input
- it just needed a market to drive its use.&nbsp; Well, the exposure Linux
will give X Windows may be that driving force.&nbsp; We'll have to wait
and see.
<P><A HREF="mailto:tvaughan@mail.diac.com">Thomas Vaughan</A> writes:
<UL>My work involves writing code in Iris GL and OpenGL.&nbsp; I am particularly
interested in accelerated 3D graphics, as I just bought a ViRGE 3D accelerator
for my home PC which runs linux 24 hours a day.&nbsp; I have played with
Mesa, but there is apparently no real free hardware support yet.</UL>
<B><I><FONT COLOR="#993300">'Muse:</FONT></I></B>&nbsp; No free support,
but <A HREF="http://www.xi.com">Xi Graphics</A> has recently announced
ViRGE 3D support in their commercial Accelerated X server.
<UL>The GGI project sounds interesting, but I don't really know whether
it's worth investigating seriously yet.</UL>
<B><I><FONT COLOR="#993300">'Muse:</FONT></I></B>&nbsp; I don't really
like the idea of GGI, partly because I don't think sticking the graphics
driver in the kernel is a good idea but also because I don't want to see
the desktop interface splintered into seperate camps.&nbsp; X is just really
coming into its own on the desktop and I'd like to see it continue.
<UL>At work my supervisor has, on my advice, just made a capital request
for a graphics card based on the 3D Labs Permedia chip which comes with
accelerated OpenGL support for Windows NT.&nbsp; In the back of my mind,
I am hoping that I can convince people at work to give linux a serious
look as a low-cost alternative to the SGI platform. After all, even with
GNU/Win32, the NT platform is not nearly as nice as real Linux.&nbsp; Unfortunately,
however, this seems just a little out-of-reach at the moment, because of
the apparent lack of 3D hardware support on Linux.&nbsp; Any news on this
front would be heartily appreciated, and I would love to write bug reports
and use either machine as a test platform.</UL>
<B><I><FONT COLOR="#993300">'Muse:</FONT></I></B>&nbsp; I got a similar
request from <A HREF="mailto:anand@noodle.med.yale.edu">Anand Rangarajan</A>:
<UL>I noticed that SuSE <A HREF="http://www.suse.de/XSuSE/XSuSE_E.html">http://www.suse.de/XSuSE/XSuSE_E.html</A>
has developed a bunch of drivers for the ELSA Gloria family of 3D graphics
cards. Will their drivers accelerate Open GL or Mesa? Also, these drivers
are free and will be integrated into the XFree 4 release.</UL>
<B><I><FONT COLOR="#993300">'Muse:</FONT></I></B>&nbsp; Well, I thought
it was about time I did a little survey of the various graphics card vendors.&nbsp;
See the <A HREF="#update_servers">X Server Update</A> article below.
<P><A HREF="mailto:mjensen@metronet.com">Marc S. Jensen</A> writes to the
<A HREF="http://www.gimp.org">GIMP User mailing list:</A>
<UL>When I run xscanimage, it complains about my system not having a /dev/scanner
device.&nbsp; So, here's my question:&nbsp; What do I do to my Red Hat
5.0 system to get a /dev/scanner device installed.&nbsp; I'm using an Adaptec
2940 SCSI adapter, and my kernel is compiled with SCSI support.&nbsp; What's
wrong here?</UL>
<B><I><FONT COLOR="#993300">'Muse:</FONT></I></B>&nbsp; Assuming your scanner
is the only deviced attached to your scsi card:
<CENTER><B><FONT SIZE=-1>ln -s /dev/sga /dev/scanner</FONT></B></CENTER>
<P>and you're all set.&nbsp; If you have more than one device connected
to the scsi bus (re: cable) then you'll need to figure out which one of
the /dev/sg[x] devices maps to your scanner.&nbsp; Then link that one to
/dev/scanner.
<P><A HREF="mailto:jlbec@ocala.cs.miami.edu">Joel Becker</A> also wrote
to the GIMP User mailing list:
<UL>Just a quick question.&nbsp; What is a reccomened drawing tablet, for
best use and easiest XInput setup?&nbsp; I think I heard the Wacom ArtPad
thrown around here.&nbsp; Also, what is a good scanner to work with SANE?&nbsp;
I mean ease of setup as well as quality of image.</UL>
<B><I><FONT COLOR="#993300">'Muse:</FONT></I></B>&nbsp; Can't answer about
the tablet, but I just happened to install a scanner recently.&nbsp; I
bought a Adaptec 2940 SCSI card and a UMAX 1200S scanner.&nbsp; The Adaptec
dropped right in on my Pentium 200MMX board with no hardware config necessary.&nbsp;
The RH 4.2 distribution I use already had the necessary scsi module prebuilt
in /lib/modules (the module name is aic7xxx.o).&nbsp; I ran <B><FONT SIZE=-1>insmod
aic7xxx</FONT></B> and up it came.
<P>The scanner I chose from the list of scanners I reviewed last year for
my <A HREF="http://www.graphics-muse.org/muse/muse.html">Graphics Muse</A>
column in the Linux Gazette.&nbsp; I first tried a 610s, but it only worked
in greyscale modes.&nbsp; So I exchanged it for the more expensive (about
$250) 1200s.&nbsp; Works quite well with the Umax drivers.&nbsp; Image
quality is excellent.&nbsp; I've been scanning hardware (twisted pair and
thinnet cables), and my hand once, and the scans were quite good although
very dark.&nbsp; I just brightened them up with xv and the GIMP and all
was well.
<P>However, I haven't tried the scanner and drivers in conjunction with
SANE.
<P>Marco Iannacone wrote:
<UL>First of all I want to say thanks for all the great stuff you wrote
(and still write) about Linux &amp; Graphics.</UL>
<B><I><FONT COLOR="#993300">'Muse:</FONT></I></B>&nbsp; No problem.
<UL>Since a friend of mine uses Photoshop on Mac, I wanted to show how
powerfull is Linux, so I installed RedHat 5.0 on a Pentium 166 with 64Mb
of RAM, with a Matrox Mystique.&nbsp; When I showed him GIMP he was REALLY
impressed but he found it quite slowly compared to Photoshop. I told him
that the reason was probably that XFree86 was using the generic SuperVGA
driver since it doesn't have a native driver for it.</UL>
<B><I><FONT COLOR="#993300">'Muse:</FONT></I></B>&nbsp; Possibly, but that
would only make a difference in screen updates.&nbsp; The majority of the
GIMP's processing is done before it updates the screen.
<UL>Is that true or maybe GIMP is only slower that Photoshop?</UL>
<B><I><FONT COLOR="#993300">'Muse:</FONT></I></B>&nbsp; Define "slower"?&nbsp;
Slower loading the same file?&nbsp; Slower in computing a new brightness
or contrast?&nbsp; Slower how?
<P>What he might be talking about is the use of tiles, which may appear
to update slowly, wherease in Photoshop they may all appear almost at once
(I've never used Photoshop, so I don't know if this is true or not).&nbsp;
So before I can answer "is GIMP slower than Photoshop" I need to know by
what means you've been measuring the two.
<UL>More than this I was not able to open any GIF, JPG or TIFF coming from
Photoshop... do you know the reason?</UL>
<B><I><FONT COLOR="#993300">'Muse:</FONT></I></B>&nbsp; You may not have
installed the proper image libraries.&nbsp; Download the <A HREF="ftp://ftp.ctd.comsat.com/pub/linux/ELF">libgr</A>
package and install it, then try again.&nbsp; You may want to build the
GIMP from the sources, after you install the libraries in the libgr package.&nbsp;
Or, if you installed GIMP from one of the distributions (Red Hat, Debian,
etc) you may want to verify you installed all the graphics libraries that
came with that distribution too.
<P><A HREF="mailto:ta3153@turkuamk.fi">Tero Auvinen</A> wrote:
<UL>In a past Graphics Muse you wrote:
<UL>...from the archive of shaders from Guido Quaroni. This archive includes
shaders from the RenderMan Companion by Steve Upstill, from Texturing and
Modeling by Ebert, Musgrave, et al, Larry Gritz, and various other places.</UL>
Where could I get this semi-wonderous package? Found one link from BMRT
homepage, but it was defunct (anonymous ftp access denied). If you'd happen
to have it somewhere, I'd appreciate a copy, otherways I'll just go and
grab everything from the aforementioned fellows homepages etc.</UL>
<B><I><FONT COLOR="#993300">'Muse:&nbsp;</FONT></I></B> If the link from
Larry's page (<A HREF="http://www.seas.gwu.edu/student/gritz/bmrt.html">the
BMRT home page</A>) is not working I'm not certain where this package can
be found.&nbsp; Try the Renderman Repository: <A HREF="http://rmr.spinne.com/">http://rmr.spinne.com/</A>.
<UL>Also hmm, I might've missed it, highly possible, but I remember that
you 'promised' a 3 part BMRT special,&nbsp; seen 2 so far(issues 15&amp;17),
maybe in march issue?</UL>
<B><I><FONT COLOR="#993300">'Muse:</FONT></I></B>&nbsp; No, there wasn't
a third part.&nbsp; I wanted to do one but I'm not that experienced with
it and I had too many other things come up.&nbsp; I've never had a chance
to go back and revisit it.
<UL>Re: Modellers:&nbsp; I can't seem to find one GOOD one, if it's nice
to look and use at, then it won't export RIB, or does it in a silly way,
using polygons and whatnot, one'd prefer RMan primitives huh? Sure I can
do the basic primitives in a non-wysiwyg way, the ascii way. But anything
more complex, no thanks.</UL>
<B><I><FONT COLOR="#993300">'Muse:</FONT></I></B>&nbsp; No modellers are
available for Linux which export RIB primitives.&nbsp; All of the ones
I know of export polygons only.
<UL>I've been thinking on getting another computer, running only MSWindows,
networked together with linux, I could edit [3D models] using Rhino or
equivalent free Win95/NT modeler and render in Linux. (oh yeah, now there's
Win32 port of BMRT even...but Linux I will NOT leave, Windows generally
drives me nuts). Only if I had the money.</UL>
<B><I><FONT COLOR="#993300">'Muse:</FONT></I></B>&nbsp; You couldn't pay
me to run MS on anything.&nbsp; But thats just me.
<UL>You happen to know what Larry uses for modeling? (besides Alias on
SGI sighs..)</UL>
<B><I><FONT COLOR="#993300">'Muse:</FONT></I></B>&nbsp; I think he's got
some big boxes, SGI's and Sun's probably.&nbsp; I'm sure Pixar feeds him
well.&nbsp; On Linux he may be using AC3D (as do I).&nbsp; Its a pretty
good modeller, but still exports everything as polygons only.&nbsp; It
does import 3DS and Lightwave files, though.&nbsp; Thats quite useful for
using the canned models from the various model sites and CDs that are available.&nbsp;
AC3D - <A HREF="http://www.comp.lancs.ac.uk/computing/users/andy/ac3dlinux.html">http://www.comp.lancs.ac.uk/computing/users/andy/ac3dlinux.html</A>.
<P><A HREF="mailto:marsel@lex.infi.net">Marsel Osipov</A> writes:
<UL>I am starting a project called Virtuoso.&nbsp; It's a 3D Modeling/Animation/Rendering
package for Linux.&nbsp;&nbsp; I am sure that I would not be able to create
a high quality package by myself, so if you would like to join, visit my
home page for more info. <A HREF="http://www.geocities.com/SiliconValley/Lakes/7705/">http://www.geocities.com/SiliconValley/Lakes/7705/</A></UL>
<B><I><FONT COLOR="#993300">'Muse:&nbsp;</FONT></I></B> We can never have
too many modellers.
<BR>&nbsp;
<P>
<HR WIDTH="100%">
<BR><A NAME="webwonderings"></A>
<BR><IMG SRC="../gx/hammel/webwonderings.jpg" HEIGHT=57 WIDTH=246>
<H2>
XeoMenu 1.1</H2>
One of the problems with pages based around standard HTML constructs is
the inability to easily modify navigation aides.&nbsp; A navigation aid
can be a set of text links, a set of images with individual links or it
can be an image map using hot spots for links.&nbsp; These tools allow
readers of a page to move around a Web site easily.&nbsp; Properly done,
they can remove the linearity (the hierarchical structure) of a Web site
and allow the reader to move freely between pages.
<P>Adding an text links is fairly easy to do and updating them simply requires
editing the HTML.&nbsp; But text links lack pizazz.&nbsp; Images used as
text links are better, but aside from using JavaScript to do image rollovers,
the images are fairly static.&nbsp; They lack the feel of a real user interface.&nbsp;
Image maps are no better and, in fact, don't even allow rollover changes
as easily making them even more static than individual images used as links.
<P>Fortunately, issues such as this is part of why Java exists.&nbsp; Java
allows for more programmatic interfaces.&nbsp; These interfaces can take
on the more familiar menu-based interfaces that readers will be accustomed
to.&nbsp; Although it can be argued that such interfaces are not any better
than static image maps, for the sake of this article we'll assume that
menuing systems are a good thing.
<P><B><FONT COLOR="#CC6600">XeoMenu</FONT></B> is a simple Java program
from Patrick Chan at Xeo (<A HREF="http://www.xeo.com">www.xeo.com</A>)
that overlays a menuing system over an image in a Web page.&nbsp; The program
is run as an applet and is used by embedding it within HTML source code.&nbsp;
Readers can retrieve a copy from <A HREF="http://java.sun.com:81/share/classes/menu/source/source.html">http://java.sun.com:81/share/classes/menu/source/source.html.&nbsp;
</A>Java source code is included, along with an example HTML file, sample
images, a users manual (a sort of man page in HTML) and the compiled Java
byte code.&nbsp; There is also a second version of the code, called horizMenu,
that permits menus to be layed out horizontally instead of vertically.&nbsp;
Since I can't seem to get Java working on my Red Hat 4.2 system (neither
through the javac compiler nor through my version of Vibe - something about
my CLASSPATH is not set up right I think), I won't be able to provide information
on compiling the source in this article.&nbsp; If I do get javac and/or
Vibe working, I'll start talking about how to compile Java programs.&nbsp;
If anyone has a write up of what I need to do to get my stock RH 4.2 version
of the Java compilers working, please drop me a line.
<P>To use XeoMenu you need to first create an image that contains two parts:&nbsp;
The menu as it is displayed without the mouse over the image and the image
as it would look if the mouse were over different parts of the original.&nbsp;
For our example, we'll use the following image:
<P><IMG SRC="./gx/hammel/xeomenu-1.gif" HSPACE=5 VSPACE=5 BORDER=2 HEIGHT=200 WIDTH=300 ALIGN=LEFT>
The image is divided into 2 halves.&nbsp; The left half is the image as
it displays without the mouse over it.&nbsp; The image is actually going
to be subdivided into a top (Linux) and bottom (Gazette) section.&nbsp;
The right side, then, shows how each section will be displayed when the
mouse is over that section.&nbsp; For example, if the mouse is over the
word Linux in the image then the blue Linux text will be displayed.&nbsp;
By default, the red colors (the left half of the image) is displayed.
<P>Now, in order not to annoy readers without Java support, you need to
move to the <A HREF="xeomenu.html">next section of this article,</A> which
will show how the Java application is used and what it looks like when
it runs.&nbsp; You will need a Java compatible browser to view this part
of the article.
<H4>
<BR>
<BR clear="both">
<A NAME="xeomenu-summary"></A></H4>
<H4>
Summary</H4>
This was just a simple example.&nbsp; XeoMenu itself comes with a more
sophisticated example, but there is no real explanation (ie documentation)
of what is going on in the code.&nbsp; Hopefully, between that example,
the user manual, and this article you'll be able to do something useful
with XeoMenu.&nbsp; The <A HREF="http://java.sun.com/applets/index.html">main
applet page</A> for&nbsp; Java.sun.com shows an example of the horizontal
version of XeoMenu running and its quite slick.&nbsp; Although the interface
uses a fairly large number of optional parameters and the format for menu
descriptions is less than ideal, it is still a useful tool that takes only
a little getting used to in order to make a very usable menu-based interface
for your Web pages.
<BR>
<HR WIDTH="100%">
<P><A NAME="musings"></A>
<BR>&nbsp;
<TABLE BORDER=0 COLS=1 WIDTH="100%" >
<TR>
<TD><IMG SRC="../gx/hammel/musings.gif" ALT="Musings" HEIGHT=52 WIDTH=247 ALIGN=LEFT></TD>
</TR>
</TABLE>
&nbsp;
<BR>&nbsp;
<BR>&nbsp;
<TABLE BORDER=0 COLS=1 WIDTH="100%" BGCOLOR="#000000" NOSAVE >
<TR NOSAVE>
<TD NOSAVE><IMG SRC="../gx/hammel/cleardot.gif" HEIGHT=3 WIDTH=3></TD>
</TR>
</TABLE>
&nbsp;
<TABLE BORDER=0 COLS=3 WIDTH="100%" NOSAVE >
<TR NOSAVE>
<TD VALIGN=TOP WIDTH="49%" NOSAVE>
<H2>
<A NAME="update_servers"></A>X Server Update</H2>
&nbsp;&nbsp; I've been doing this column now for over a year and writing
for Linux Journal on and off for another year.&nbsp;&nbsp; In that time
I haven't really addressed one of the more obvious topics related to doing
graphics on Linux - the X server.&nbsp; Part of the reason for that is
that I don't have the resources to test a bunch of different server configurations.&nbsp;
If I got paid to do this it would be a different story, but this column
is born from whatever time and system resources I can spare each month.&nbsp;
<P>&nbsp;&nbsp; Still, I get requests fairly often asking for information
about what 3D video cards are supported under Linux and which ones support
various hardware extensions such as the X Input Extension.&nbsp; Most of
the questions specifically ask "which are supported under XFree86".&nbsp;
But some readers ask about support in general, either free or commercial.&nbsp;
<P>&nbsp;&nbsp; Well, I thought it was time I sent a query to the various
vendors and find out where things stand.&nbsp; The email I sent was fairly
generic.&nbsp; It read as follows:&nbsp;
<BR>&nbsp;
<ADDRESS>
Do you have any information which I may use in my column related to your
current or planned support for 3D hardware acceleration (specifically related
to OpenGL/Mesa, but not necessarily so)?&nbsp; What about support for alternative
input devices via the X Input Extension.&nbsp; The GIMP, and its X toolkit
Gtk, both make use of X Input if available and I expect many other tools
will do so as well in the near future.</ADDRESS>
<P>This query was sent out around the 12th of this month to <A HREF="http://www.xig.com">Xi
Graphics</A>, <A HREF="http://www.metrolink.com">Metro Link</A>, <A HREF="http://www.suse.de">SuSE</A>,
and the <A HREF="http://www.xfree86.org">XFree86</A> project.&nbsp; I received
responses from all 4, however Metro Link did not receive my query immediately
and so their response came in too late for this article.&nbsp; I will cover
Metro Link's response next month.&nbsp;&nbsp; Please note that this article
is intended to <I>list</I> which servers support what features/devices
and is not intended to explain how to use those features.&nbsp;
<P>The responses have been edited to remove what appeared to be editorial
comments, where recognizable.&nbsp; I will refrain from editorializing
on these responses in this article as well.&nbsp;
<P>&nbsp;&nbsp; The first reply was nearly immediate and came from <A HREF="mailto:hohndel@suse.de">Dirk
H Hohndel</A> at SuSE.&nbsp; He sent two emails, one as the Vice President
of The XFree86 Project, Inc. and one as the Lead Developer, S.u.S.E. GmbH.&nbsp;
Dirk wears both hats, and therefore his comments are considered official
responses, one from each organization.&nbsp; Both responses were direct
and to the point.&nbsp; First his XFree86 response:&nbsp;
<BR>&nbsp;
<CENTER><TABLE BORDER=0 COLS=1 WIDTH="95%" NOSAVE >
<TR NOSAVE>
<TD NOSAVE>Well, XSuSE and XFree86 are mostly identical. As far as legally
possible, all work done on XSuSE is integrated into the next XFree86 version.
XFree86 in itself focuses on the X Window System and 2D support for the
different cards. While they are not actively pursuing 3D support, they&nbsp;
are in contact with several groups working in that area.&nbsp;
<P>I do not speak for Metro Link, but I can tell you that Metro Link and
XFree86 are in very positive cooperation on the 2D side of servers.&nbsp;
Metro Link donated lots of code to XFree86 recently, and Metro Link and
XFree86 are working together on many aspects of the design of our future
X servers.&nbsp;
<BR>&nbsp;</TD>
</TR>
</TABLE></CENTER>
Because Dirk's response came quickly, and because responses from the other
vendors provided more detailed information, I thought I should offere XFree86
a chance to expand their reply.&nbsp; When asked to comment on architectural
details and XFree86's relationship to the commercial vendors, Dirk responded:&nbsp;
<BR>&nbsp;
<CENTER><TABLE BORDER=0 COLS=1 WIDTH="95%" NOSAVE >
<TR NOSAVE>
<TD NOSAVE>Why would I bore you or anyone else with architectural details
that no one really cares about.&nbsp;
<BR>&nbsp;</TD>
</TR>
</TABLE></CENTER>
He followed up his XFree86 reply with a response from SuSE:&nbsp;
<BR>&nbsp;
<CENTER><TABLE BORDER=0 COLS=1 WIDTH="95%" NOSAVE >
<TR NOSAVE>
<TD NOSAVE>SuSE is working on hardware 3D support, but there is no release
date for that, yet.&nbsp;
<P>The 2D drivers from SuSE are intended to be integrated into XFree86-4.0,
but we are currently running into some legal problems with that for one
of them (3DLabs GLINT), as some of the docs are under NDA and we have not
been able to get the permission to release sources, yet. We are working
on it, though.&nbsp; All the other drivers from SuSE have already been
included into XFree86-3.3.2</TD>
</TR>
</TABLE></CENTER>
<P>The other replies came from Xi Graphics.&nbsp; Both Thomas Roell, President
of Xi Graphics and technical architect for their servers, and Jeremy Chatfield
responded.&nbsp;
<P>Thomas wrote:&nbsp;
<BR>&nbsp;
<CENTER><TABLE BORDER=0 COLS=1 WIDTH="95%" NOSAVE >
<TR NOSAVE>
<TD NOSAVE>Our next generation X-Server will support additional new input
devices for the XInputExtension. The extension itself is supported since
Accelerated-X 4.1. Planned devices are mainly CAD oriented input systems,
like Tablets, Touchscreens and Space-Balls.&nbsp; As for Hardware 3D, you
can bet that the next generation will have that.</TD>
</TR>
</TABLE></CENTER>
<P>Jeremy Chatfield followed up with the following (edited partially for
length):&nbsp;
<BR>&nbsp;
<CENTER><TABLE BORDER=0 COLS=1 WIDTH="95%" NOSAVE >
<TR NOSAVE>
<TD NOSAVE>Accelerated-X 4.1 supports the XInputExtension, using a small
and fixed list of devices, with very limited device management.&nbsp; Future
releases will support a wider range of devices.&nbsp;
<P>We've been evolving Accelerated-X ever since 1994, to take advantage
of 3D hardware acceleration.&nbsp; Examples of the technology introductions
and the reason for needing them for 3D support:
<UL>
<LI>
Memory allocation and buffer management.&nbsp; 3D uses a lot of memory.&nbsp;
Standard malloc() (as of 1994, when we started this work) did not permit
programs to decrease in size, tended to thrash memory when freeing and
sometimes when allocating, and exhibited other behaviors that were not
suitable to long running processes with a mix of temporary and long term
storage in a wide variety of data sizes.&nbsp; We do things like lazy buffer
allocation, only allocating stencil buffers when needed, and so on.&nbsp;
This improves speed and reduces system impact, seen in total Server size,
and paging demand.</LI>
</UL>
</TD>
</TR>
</TABLE></CENTER>
&nbsp;
<CENTER></CENTER>
<CENTER><A HREF="#next-column">-Top of next column-</A></CENTER>
</TD>
<TD WIDTH="1%" BGCOLOR="#000000" NOSAVE><IMG SRC="../gx/hammel/cleardot.gif" HEIGHT=3 WIDTH=3></TD>
<TD VALIGN=TOP WIDTH="49%" NOSAVE>
<TABLE BORDER=0 COLS=1 WIDTH="100%" NOSAVE >
<TR>
<TD><LH><A NAME="next-column"></A><B>More Musings...</B>&nbsp;</LH>&nbsp;
<LI>
<A HREF="vrwave.html">VRWave 0.9</A></LI>
<BR>--</TD>
</TR>
<TR NOSAVE>
<TD BGCOLOR="#000000" NOSAVE><IMG SRC="../gx/hammel/cleardot.gif" HEIGHT=3 WIDTH=3></TD>
</TR>
<TR NOSAVE>
<TD NOSAVE>
<CENTER><TABLE BORDER=0 COLS=1 WIDTH="95%" NOSAVE >
<TR NOSAVE>
<TD NOSAVE>
<UL>
<LI>
Coprocessor locking.&nbsp; When using the host processor, graphics engine
and 3D engine, all writing in the same memory areas, and when using both
system memory (via AGP) and graphics board memory, fast and correct mutex
locking is essential.&nbsp; [Without locking] this will cause problems
when all three processors (or more) attempt to handle the same memory.&nbsp;
We have continued to refine our mutex locking for several years, though
this is not visible in any product other than multihead, at present.&nbsp;</LI>
</UL>
<UL>
<LI>
Asynchronous I/O&nbsp; When X Servers with high levels of hardware acceleration
are handling buffered drawing requests, keyboard and mouse input is put
into the end of the queue.&nbsp; This results in sluggish response, and
in mouse and keyboard data being handled in bursts.&nbsp; Mouse acceleration
can be triggered inappropriately, so mouse motion becomes very hard to
control, and sequential single button clicks can be misinterpreted as double
clicks.&nbsp; We introduced the "Velvet Mouse" mechanism to permit input
even while the Server was in heavy rendering, as will be typical of 3D
dynamic applications.&nbsp;</LI>
</UL>
<UL>
<LI>
Overlays.&nbsp; Many 3D applications on workstations rely on the presence
of overlays.&nbsp; [Overlays] also benefit from the memory management and
other architectural changes in Accelerated-X.</LI>
</UL>
</TD>
</TR>
</TABLE></CENTER>
Xi Graphics recently announce support for ViRGE 3D (see the <A HREF="http://www.graphics-muse.org">February
1998 Graphics Muse</A>).&nbsp;
<P>Beyond these two vendors, there is also 3D hardware support available
for Mesa for the following video hardware:&nbsp;
<UL>
<LI>
3Dfx Voodoo - Cards based on the 3Dfx Voodoo chipset (such as Diamond Monster
3D and Orchid - Righteous 3D) are supported under Linux and Windows 95.
Look <A HREF="http://www-hmw.caribel.pisa.it/fxmesa/index.shtml">here</A>
for the latest info. This is the best supported 3-D hardware for Linux
at this time.&nbsp;</LI>
</UL>
<UL>
<LI>
3Dfx Voodoo Rush (rendering into window) - Supported under Windows. Linux
support is underway.&nbsp;</LI>
</UL>
<UL>
<LI>
GLINT-based boards - Look <A HREF="http://fantasia.eng.clemson.edu:80/~adamsk/glint_index.html">here</A>
for the latest info.&nbsp;</LI>
</UL>
<UL>
<LI>
Cirrus Mondello - No longer supported- download Mesa 1.2.8 if you're interested
in this driver.&nbsp;</LI>
</UL>
This information was taken directly from the <A HREF="http://www.ssec.wisc.edu/~brianp/Mesa.html">Mesa
Web pages.&nbsp; </A>I ignored any cards for which Linux was not mentioned
except the Cirrus Mondello.&nbsp; I don't know if its for Linux or Windows.&nbsp;
Also, I don't know exactly how Mesa makes use of this hardware without
actually being part of the X server.&nbsp; You will have to investigate
the Mesa pages and its links for more information in that area.&nbsp;
<P>So, now you should know as much as I do with respect to 3D and X Input
support from XFree86/SuSE and Xi Graphics.&nbsp; In summary, most of the
3D work seems to be planned and under development, but no word on when
the support (at least for wide spread 3D support) will be available.&nbsp;
Neither XFree86/SuSE nor Xi specifically mentioned any 3D boards being
supported, although Xi did have the announcement for the ViRGE 3D last
month.&nbsp; Xi stated they support the X Input Extension in their Accelerated-X
4.1 release.&nbsp; Although XFree86 didn't mention it, I know that X Input
is supported in their product as well.&nbsp; Don't forget:&nbsp; I'll be
covering Metro Link's responses to my query next month.&nbsp;
<P>I should mention again that I have worked for Xi Graphics in the past,
and in fact worked with both Thomas and Jeremy at Dell computer and with
Jeremy at Information Foundation (a USL source code licensee back around
1993 or so).&nbsp; I have made every attempt to remove all editorial comments,
both my own and any from the respondents, from this article.
<H4>
Contact Information</H4>
<B>XFree86</B>:
<UL>
<LI>
Announcements:&nbsp; <A HREF="news:comp.os.linux.announce">comp.os.linux.announce</A>
and other announcement groups</LI>
<LI>
Web site:&nbsp; <A HREF="http://www.xfree86.org">http://www.xfree86.org</A></LI>
<LI>
Support:&nbsp; <A HREF="mailto:XFree86@XFree86.Org">XFree86@XFree86.Org</A></LI>
<LI>
Business: <A HREF="mailto:BOD@XFree86.Org">BOD@XFree86.Org</A></LI>
<BR><A HREF="http://www.xfree86.org"></A>&nbsp;</UL>
<B>S.u.S.E</B>.:
<UL>
<LI>
Announcements: <A HREF="news:comp.os.linux.announce">comp.os.linux.announce</A></LI>
<LI>
Web site:&nbsp; <A HREF="http://www.suse.de/XSuSE/XSuSE_E.html">http://www.suse.de/XSuSE/XSuSE_E.html</A></LI>
<LI>
Support:&nbsp; <A HREF="mailto:x@suse.de">x@suse.de</A></LI>
<LI>
Business: <A HREF="mailto:x@suse.de">x@suse.de</A></LI>
</UL>
Dirk reports:&nbsp; In both cases we try to keep the web pages up to date
and XFree86 has a FAQ online that contains workarounds for known bugs.
<P><B>Xi Graphics</B>:
<UL>
<LI>
Announcements: <A HREF="mailto:accelx-announce-request@xig.com">accelx-announce-request@xig.com
</A>with the one word message "subscribe"</LI>
<LI>
Web: <A HREF="http://www.xig.com">http://www.xig.com</A></LI>
<LI>
User-to-User mailing list:&nbsp; <A HREF="mailto:accelx-users-request@xig.com">accelx-users-request@xig.com</A>
with the one word message "subscribe"</LI>
<LI>
Email:&nbsp; <A HREF="mailto:sales@xig.com">sales@xig.com</A>&nbsp;&nbsp;
- automated initial response, but a human reader.</LI>
<LI>
Phone:&nbsp; +1 800 946-7433 (US), +1 303 298-7478 (Int'l).</LI>
<LI>
Fax:&nbsp;&nbsp;&nbsp; +1 303 298-1406</LI>
</UL>
Jeremy added:&nbsp; We keep the web site up to date.</TD>
</TR>
</TABLE>
&nbsp;</TD>
</TR>
</TABLE>
&nbsp;
<TABLE BORDER=0 COLS=1 WIDTH="100%" BGCOLOR="#000000" NOSAVE >
<TR NOSAVE>
<TD NOSAVE><IMG SRC="../gx/hammel/cleardot.gif" HEIGHT=3 WIDTH=3></TD>
</TR>
</TABLE>
&nbsp;
<TABLE BORDER=0 COLS=1 WIDTH="100%" >
<TR>
<TD><IMG SRC="../gx/hammel/resources.gif" ALT="Resources" HEIGHT=57 WIDTH=246 ALIGN=LEFT></TD>
</TR>
</TABLE>
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>&nbsp;
<TABLE BORDER=0 COLS=2 WIDTH="100%" NOSAVE >
<TR NOSAVE>
<TD NOSAVE><A HREF="http://www.csn.net/~mjhammel/linux/lgh.html">Linux
Graphics mini-Howto</A>&nbsp;
<BR><A HREF="http://www.csn.net/~mjhammel/ugu/ugu.html">Unix Graphics Utilities</A>&nbsp;
<BR><A HREF="http://www.digiserve.com/ar/linux-snd/">Linux Multimedia Page</A>&nbsp;
<P>Some of the Mailing Lists and Newsgroups I keep an eye on and where
I get much of the information in this column:&nbsp;
<P><A HREF="http://www.gimp.org">The Gimp User and Gimp Developer Mailing
Lists</A>.&nbsp;
<BR><A HREF="http://www.irtc.org">The IRTC-L discussion list</A>&nbsp;
<BR><A HREF="news:comp.graphics.rendering.raytracing">comp.graphics.rendering.raytracing</A>&nbsp;
<BR><A HREF="news:comp.graphics.rendering.renderman">comp.graphics.rendering.renderman</A>&nbsp;
<BR><A HREF="news:comp.graphics.api.opengl">comp.graphics.api.opengl</A>&nbsp;
<BR><A HREF="news:comp.os.linux.announce">comp.os.linux.announce</A>&nbsp;</TD>
<TD><IMG SRC="../gx/hammel/gmuse.jpg" HSPACE=10 HEIGHT=270 WIDTH=190></TD>
</TR>
</TABLE>
<A NAME="future"></A>
<H2>
Future Directions</H2>
Next month:&nbsp;&nbsp; Unknown.&nbsp; I've got some prior obligations
(paying ones, that is) that I absolutely <B><I>must</I></B> get done.&nbsp;
And soon.
<P><A HREF="mailto:mjhammel@csn.net">Let me know what you'd like to hear
about!</A>
<P>
<HR WIDTH="100%">
<DIV ALIGN=right><FONT SIZE=-1>&copy; 1998 <A HREF="mailto:mjhammel@csn.net">Michael
J. Hammel</A></FONT></DIV>
<!--===================================================================-->
<P> <hr> <P>
<center><H5>Copyright &copy; 1998, Michael J. Hammel <BR>
Published in Issue 26 of <i>Linux Gazette</i>, March 1998</H5></center>
<!--===================================================================-->
<P> <hr> <P>
<A HREF="./index.html"><IMG ALIGN=BOTTOM SRC="../gx/indexnew.gif"
ALT="[ TABLE OF CONTENTS ]"></A>
<A HREF="../index.html"><IMG ALIGN=BOTTOM SRC="../gx/homenew.gif"
ALT="[ FRONT PAGE ]"></A>
<A HREF="./marsden.html"><IMG SRC="../gx/back2.gif"
ALT=" Back "></A>
<A HREF="./kapok/kapok-nonote.html"><IMG SRC="../gx/fwd.gif" ALT=" Next "></A>
<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"></A>
<TABLE BORDER=0 NOSAVE >
<TR NOSAVE>
<TD NOSAVE>
<H2>
More...</H2>
<IMG SRC="../gx/hammel/musings.gif" ALT="Musings" HEIGHT=52 WIDTH=247 ALIGN=LEFT>&nbsp;</TD>
</TR>
</TABLE>
&nbsp;
<TABLE>
<TR>
<TD></TD>
</TR>
</TABLE>
<IMG SRC="../gx/hammel/cleardot.gif" ALT="indent" VSPACE=5 HEIGHT=1 WIDTH=1 ALIGN=LEFT>
<TABLE BORDER=0 WIDTH="100%" NOSAVE >
<TR NOSAVE>
<TD ALIGN=RIGHT WIDTH="100%" NOSAVE><FONT SIZE=-2>&copy; 1998 <A HREF="mailto:mjhammel@csn.net">Michael
J. Hammel</A>&nbsp;</FONT></TD>
</TR>
<TR>
<TD VALIGN=TOP BGCOLOR="#000000" cellpadding="0" cellspacing="0"><IMG SRC="../gx/hammel/cleardot.gif" ALT="indent" ALIGN=LEFT></TD>
</TR>
</TABLE>
<H2>
VRWave 0.9</H2>
Quite some time ago a reader, a fellow named Paulo, had sent me email asking
if I had taken a look at <B><FONT COLOR="#CC6600">VRWave</FONT></B> yet.&nbsp;
This is a VRML 2.0 browser available from the Institute for Information
Processing and Computer Supported New Media (IICM), GrazUniversity of Technology,
Austria.&nbsp; The program is freely available for private use and includes
source code.&nbsp; The current version, 0.9, includes a Java-based port
of the code, although all rendering code is still in C using either OpenGL
or Mesa.
<P>Looking through my backlog of things to do for the Muse, I decided to
take a look at VRWave.&nbsp; At a minimum I wanted to see if I could simply
get it to run.&nbsp; Hopefully, I would be able to say something intelligent
about the source code and build environment as well.&nbsp; I jumped on
the Internet and went off to grab a copy of the package from a US mirror
of the VRWave Home Page (<A HREF="http://www.iicm.edu/vrwave">http://www.iicm.edu/vrwave</A>).&nbsp;
The first thing I noticed was that there were both source and binary distributions
available.&nbsp; The binary distributions cover a few flavors of Unix,
including ports for Linux 2.0.&nbsp; There are actually two versions of
the binary distribution - a Java 1.1.3 based version and a Mesa version
which uses Java 1.0.2.&nbsp; These are actually the platform specific libraries
needed by VRWave.&nbsp; I grabbed both along with the gzipped Common tar
file which must accompany any binary version that is downloaded.&nbsp;&nbsp;
The Mesa version is not compiled with any of the hardware accelerated drivers
available for Mesa.&nbsp; If you want to use those drivers you need to
recompile the source with the Mesa package properly built with the drivers
of interest.&nbsp; Also, the Mesa code is statically linked into the platform
specific libraries, so you shouldn't need any other libraries or files
outside of those contained in the&nbsp; Common tar file and the platform
specific tar file.
<P>The directions say to unpack the Common file first, then cd into the
vrwave-0.9 directory this process creates and unpack the platform specific
files.&nbsp; The first time I did this I didn't do it in the right order
and got myself confused.&nbsp; So I redid the unpacking, following the
directions.&nbsp; Its true - men never read the directions.&nbsp; The instructructions
in the INSTALLATION file for running VRWave are quite complete so I won't
rehash them here.&nbsp; Just be sure you actually read the file!&nbsp;
In my environment I use Java 1.0.2, the default installation of Java on
Red Hat 4.2, so I set my CPU environment variable to LINUX_ELF.&nbsp; You
may need to set it to LINUX_J113 if you have the Java 1.1.3 package installed
on your system.
<P>Once you set up a couple of environment variables you're ready to start
vrwave.&nbsp; Since VRWave uses your Java runtime environment, be sure
your CLASSPATH&nbsp;is set correctly first.&nbsp; On my Red Hat 4.2 system
I&nbsp;have it set as follows:
<UL><B><FONT SIZE=-1>CLASSPATH=/usr/lib/java/lib:/usr/lib/java/lib/classes:/home/mjhammel/src/graphics/vrwave-0.9/classes</FONT></B></UL>
Type <B>vrwave </B>and the interface opens a window.&nbsp; On my system
I got messages like the following:
<P><B>java.lang.InternalError: unsupported screen depth</B>
<BR><B>VRwave: could not load icons at /home/mjhammel/src/graphics/vrwave2/vrwave-0.9/icons.gif</B>
<BR><B>VRwave: could not load logo at /home/mjhammel/src/graphics/vrwave2/vrwave-0.9/logo.gif</B>
<BR><B>java.lang.InternalError: unsupported screen depth</B>
<BR><B>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; at sun.awt.image.ImageRepresentation.setPixels(ImageRepresentation.java:170)</B>
<BR><B>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; at sun.awt.image.InputStreamImageSource.setPixels(InputStreamImageSource.java:459)</B>
<BR><B>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; at sun.awt.image.GifImageDecoder.sendPixels(GifImageDecoder.java:243)</B>
<BR><B>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; at sun.awt.image.GifImageDecoder.readImage(GifImageDecoder.java:295)</B>
<BR><B>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; at sun.awt.image.GifImageDecoder.produceImage(GifImageDecoder.java:155)</B>
<BR><B>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; at sun.awt.image.InputStreamImageSource.doFetch(InputStreamImageSource.java:215)</B>
<BR><B>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; at sun.awt.image.ImageFetcher.run(ImageFetcher.java:98)</B>
<BR><B>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; at sun.awt.image.ImageRepresentation.setPixels(ImageRepresentation.java:170)</B>
<BR><B>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; at sun.awt.image.InputStreamImageSource.setPixels(InputStreamImageSource.java:459)</B>
<BR><B>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; at sun.awt.image.GifImageDecoder.sendPixels(GifImageDecoder.java:243)</B>
<BR><B>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; at sun.awt.image.GifImageDecoder.readImage(GifImageDecoder.java:295)</B>
<BR><B>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; at sun.awt.image.GifImageDecoder.produceImage(GifImageDecoder.java:155)</B>
<BR><B>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; at sun.awt.image.InputStreamImageSource.doFetch(InputStreamImageSource.java:215)</B>
<BR><B>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; at sun.awt.image.ImageFetcher.run(ImageFetcher.java:98)</B><B></B>
<P>These may be due to either an incorrect Java configuration on my system
or because the Java 1.0.2 libraries do not support the TrueColor (24 bit
depth) visual I'm running with my X server.&nbsp; In either case it didn't
seem to matter, as the window opened and I was able to begin playing with
VRWave.&nbsp; Also, during all my experimentation I&nbsp;had no display
or color problems at all.
<P>The first thing I should say at this point is that I know very little
about VRML other than its a language for describing navigable 3D worlds.&nbsp;
VRML 2.0 includes features such as spatial sound, where the sound of an
object in the distance can grow louder as the object is moved closer.&nbsp;
To my knowledge VRWave does not yet support sounds, but I didn't test any
VRML worlds in which sound was availalble.&nbsp; In any case, what I'll
describe here is what an casual user might encounter, what someone who
is just beginning to explore VRML might find interesting and useful.&nbsp;&nbsp;
Also please note that the slight blur in the images is due to reducing
them from the screen captures in order to fit the image in a 640 pixel
wide Web browser.
<H4>
The interface</H4>
<CENTER>
<H4>
<IMG SRC="./gx/hammel/vrwave-1.jpg" HSPACE=10 VSPACE=10 HEIGHT=370 WIDTH=459></H4></CENTER>
&nbsp;
<P>The image above show the initial window if no input file is provided
on the command line.&nbsp; You can specify any VRML file as an input file.&nbsp;
These carry the .<B>wrl </B>extension in the file name and you can find
numerous example in the <B><FONT SIZE=-1>examples</FONT></B> directory
in the distribution.&nbsp;&nbsp; Scene files are ordinary text files, not
unlike the POV-Ray programming language in a sense.&nbsp; The look like
the sample code below, which is the code for the convexify.wrl example:
<UL>#VRML V2.0 utf8
<P># sample for applying perface materials onto non-convex shape
<BR># kwagen/mpichler
<P>Viewpoint
<BR>{
<BR>&nbsp; position 5 5.25 10
<BR>&nbsp; orientation -0.6 0.8 0.1 0.5
<BR>}
<BR>Shape
<BR>{
<BR>&nbsp; geometry IndexedFaceSet
<BR>&nbsp; {
<BR>&nbsp;&nbsp;&nbsp; coord Coordinate
<BR>&nbsp;&nbsp;&nbsp; {
<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; point [ 0 0 1, 1 0 1, 3 4 1, 2 4 1,
1 2 1, 1 4 1, 0 4 1,
<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
0 0 0, 1 0 0, 3 4 0, 2 4 0, 1 2 0, 1 4 0, 0 4 0 ]
<BR>&nbsp;&nbsp;&nbsp; }
<BR>&nbsp;&nbsp;&nbsp; coordIndex
<BR>&nbsp;&nbsp;&nbsp; [
<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0 1 2 3 4 5 6 -1&nbsp;&nbsp; # front,
lt. green
<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0 7 8 1 -1&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
# red
<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 1 8 9 2 -1&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
# blue
<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 2 9 10 3 -1&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
# yellow
<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 3 10 11 4 -1&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
# cyan
<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 4 11 12 5 -1&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
# magenta
<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 5 12 13 6 -1&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
# dk. cyan
<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 6 13 7 0 -1&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
# dk. magenta
<BR>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 13 12 11 10 9 8 7&nbsp; # back, dk.
green
<BR>&nbsp;&nbsp;&nbsp; ]
<BR>&nbsp;&nbsp;&nbsp; color Color { color [ 0 1 0, 1 0 0, 0 0 1, 1 1 0,
0 1 1, 1 0 1, 0 0.5 0.5, 0.5 0 0.5, 0 0.5 0 ] }
<BR>#&nbsp;&nbsp; colorIndex [ 8 7 6 5 4 3 2 1 0 ]&nbsp; # reverse color
binding
<BR>&nbsp;&nbsp;&nbsp; colorPerVertex FALSE
<BR>&nbsp;&nbsp;&nbsp; convex FALSE
<BR>&nbsp; }
<BR>}</UL>
&nbsp;
<P>The following table summarizes most of the features in the VRWave main
window:
<BR>&nbsp;
<CENTER><TABLE BORDER COLS=2 WIDTH="100%" NOSAVE >
<TR BGCOLOR="#FFCC00" NOSAVE>
<TD WIDTH="20%" NOSAVE><B><FONT SIZE=+1>Window Feature</FONT></B></TD>
<TD><B><FONT SIZE=+1>Description</FONT></B></TD>
</TR>
<TR NOSAVE>
<TD BGCOLOR="#33CCFF" NOSAVE>File&nbsp;</TD>
<TD>Basic file input/output functions, plus camera information.</TD>
</TR>
<TR NOSAVE>
<TD BGCOLOR="#33CCFF" NOSAVE>Navigate&nbsp;</TD>
<TD>Set mode for movement through VRML world; reset and align functions
for current view.</TD>
</TR>
<TR NOSAVE>
<TD BGCOLOR="#33CCFF" NOSAVE>Display&nbsp;</TD>
<TD>Lighting, rendering (static and interative) methods, colors, background,
transparency, etc.</TD>
</TR>
<TR NOSAVE>
<TD BGCOLOR="#33CCFF" NOSAVE>Help&nbsp;</TD>
<TD>HTML based help system that relies on Netscape.&nbsp; Netscape must
be in your path for this to function properly.</TD>
</TR>
<TR NOSAVE>
<TD BGCOLOR="#33CCFF" NOSAVE>Flip</TD>
<TD>Navigation mode;&nbsp; Scene translation around origin and zoom.</TD>
</TR>
<TR NOSAVE>
<TD BGCOLOR="#33CCFF" NOSAVE>Walk</TD>
<TD>Navigation mode;&nbsp; move forward, backwards, sideways pan and move
"eyes".</TD>
</TR>
<TR NOSAVE>
<TD BGCOLOR="#33CCFF" NOSAVE>Fly To</TD>
<TD>Navigation mode;&nbsp; sets a Point of Interest from which all other
movements in this mode are relative.</TD>
</TR>
<TR NOSAVE>
<TD BGCOLOR="#33CCFF" NOSAVE>Heads Up</TD>
<TD>Places a "heads up display" in the center of the viewing area;&nbsp;
3 navigation types in display:&nbsp; eyes, body and pan.&nbsp; These correspond
to the same types of movements that Walk provides but gives visual cues
to movement settings.</TD>
</TR>
<TR NOSAVE>
<TD BGCOLOR="#33CCFF" NOSAVE>Behaviour</TD>
<TD>Purpose unknown</TD>
</TR>
<TR NOSAVE>
<TD BGCOLOR="#33CCFF" NOSAVE>Interaction</TD>
<TD>Purpose unknown</TD>
</TR>
</TABLE></CENTER>
&nbsp;
<H4>
Navigation</H4>
In the following example, the sample scene <B><FONT SIZE=-1>examples/office2.wrl</FONT></B>
was opened (File->Open) into the default window (ie the window was not
resized or adjusted in any way).&nbsp; To move around this scene you can
use the mouse or keyboard.&nbsp; Keyboard bindings are described in the
<B><FONT SIZE=-1>help/mouse.html </FONT></B>file, which will also give
you a little more information about what kind of movements within a scene
are available.
<P>An example of movement through this scene would be to hold down the
middle mouse button (with the Flip button pressed as it is in the example
image below) and drag it around the viewing area.&nbsp; This would rotate
the entire room and its contents around the origin, which is positioned,
but not visible, in the middle of the viewing area.&nbsp; When this movement
is started the image will change to a wireframe view to speed processing.&nbsp;
The use of wireframe, flat shaded, smooth shaded and textured objects during
navigation and static display (when you aren't moving the scene around)
can be controlled from the <B>Display</B> option in the menu bar.
<BR>&nbsp;
<CENTER><IMG SRC="./gx/hammel/vrwave-3.jpg" HSPACE=10 VSPACE=10 HEIGHT=416 WIDTH=516><BR clear="both"></CENTER>
<CENTER><B>examples/office2.wrl example scene</B></CENTER>
<CENTER><IMG SRC="./gx/hammel/vrwave-4.jpg" HSPACE=10 VSPACE=10 HEIGHT=412 WIDTH=510><BR clear="both"></CENTER>
<CENTER><B>examples/office2.wrl example scene in wireframe mode</B></CENTER>
<P>This scene is probably the nicest image, asthetically speaking, of all
the examples.&nbsp; The image fills the viewable area and is a complete
room.&nbsp; If you navigate around the room you quickly learn that the
walls to the room disappear if you're viewing area would be blocked by
those walls&nbsp; For example, tilt the room down, then rotate it to the
left.&nbsp; You're view of the room is now outside of the right wall, but
in order to view the inside of the room the right wall is not drawn.&nbsp;
You can change this behaviour by using the <B><FONT SIZE=-1>Display->Two-sided
Polygons</FONT></B> option and setting this option <I>"On"</I>.&nbsp; The
default setting, <I>Auto</I>, will not display the wall if it gets in your
way.&nbsp; Turning this option on causes the back sides of the walls to
become visible, and so your view inside the room is blocked.
<CENTER><IMG SRC="./gx/hammel/vrwave-2.jpg" HSPACE=10 VSPACE=10 HEIGHT=412 WIDTH=510><BR clear="both"></CENTER>
<CENTER><B>examples/sensors/touchsensor.wrl, with the Display->Background</B></CENTER>
<CENTER><B>set to gray and the Heads Up Navigation button set.</B></CENTER>
<P>In this next example the Heads Up option is selected and you can see
the three view functions displayed in the middle of the viewing area.&nbsp;
These small boxes don't move with the rest of the scene as you drag it
around the viewing window.&nbsp; They stay centered in that window.&nbsp;
A red line is drawn from the center of one of these boxes to the current
cursor location showing direction and speed (longer lines give faster speed).
<P>The movement of the small sphere in this image is managed through the
use of the left mouse button, but only when the cursor is over the large
green box.&nbsp; Moving the cursor, left mouse button held down, moves
the sphere around the viewing area.&nbsp; If the mouse leaves the area
of the box then the sphere stops moving.&nbsp; Note that the area of the
box does not mean just a side of the box - it means what ever region of
the box is actually visible to the user.
<BR>&nbsp;
<BR>If you have a fast enough computer and enough memory you can turn on
interactive texturing.&nbsp; This allows you to view the the objects in
the scene with their full textures displayed while you move the scenes
and objects around the viewing area.&nbsp; Although I&nbsp;can't show this
feature here, I can show you another example scene which has a texture
map applied to the sides of a cube.&nbsp; The first example shows the texturing
on a cube with Two-sided Polygons turned off.&nbsp; The next example, which
is a full sized capture so you can see the details a little better, shows
the same image with Two-sided Polygons turned on.
<CENTER><IMG SRC="./gx/hammel/vrwave-5.jpg" HSPACE=10 VSPACE=10 NOSAVE HEIGHT=416 WIDTH=516><BR clear="both"></CENTER>
<CENTER><B>examples/isub/cube.wrl, with static texturing turned on</B></CENTER>
<CENTER>
<H4>
<IMG SRC="./gx/hammel/vrwave-6.jpg" HSPACE=10 VSPACE=10 HEIGHT=330 WIDTH=348><BR clear="both"></H4></CENTER>
<CENTER><B>Same image, but with two sided polygons turned on so</B></CENTER>
<CENTER><B>you can see the transparent parts of the image better.</B></CENTER>
<H4>
Visiting VRML 2.0 URLs</H4>
VRWave's beta Netscape plug-in does not work with Netscape 4.0 due to changes
from 3.0 to 4.0 in Netscapes security code.&nbsp; Since I&nbsp;use the
4.03 release at home I was not able to test the plug-in.&nbsp; Also, since
all of the VRML&nbsp;sites I visited used VRML&nbsp;embedded in HTML, and
since those pages caused my 4.03 version of Netscape to crash when I tried
to load them, I wasn't able to test the mime/type installation that would
launch VRWave as an external viewer.&nbsp; I also tried to download a newer
version of Netscape, but my connection kept timing out during the download
(its about 10Mb now).&nbsp; This is what I get for waiting till the last
few days before my deadline for this column before trying to get this all
working.&nbsp; Its my fault - not VRWaves.
<H4>
Getting Help&nbsp; and other information</H4>
There is a Help option in the menu bar at the top of the interface.&nbsp;
This requires that Netscape be in your path so that VRWave can launch it.&nbsp;
If Netscape is already running, it won't matter, since VRWave still needs
to try to run Netscape first, so it still must be in your PATH&nbsp;before
running VRWave.&nbsp; I'm not sure if I prefer this or would rather see
them use the NetHelp inteface for Netscape.&nbsp; I&nbsp;think I prefer
the latter, although NetHelp may not be accessible from Java (I&nbsp;use
an Xlib based API for it).
<P>The README file that comes with the binary distribution states that
an online users guide for VRWeb (VRWave's predecessor) is available from
http://www.iicm.edu/vrweb/help.&nbsp; However, this link doesn't seem to
work any more.&nbsp; I&nbsp;browsed the main VRWave web site and found
a link to <A HREF="http://www.iicm.edu/vrwave/release">http://www.iicm.edu/vrwave/release</A>,
which contains various online documentation.&nbsp; Unfortunately, I didn't
find a users guide per se.&nbsp; The best&nbsp; printed help available
will be the help/install.html and help/mouse.html files in the runtime
directories from the binary distribution.&nbsp; In particular, the mouse.html
file contains detailed information about mouse and keyboard bindings for
scene navigation.
<H4>
Compiling from source</H4>
The bad news here is that my Java development environment just doesn't
seem to be working and so I can't talk intelligently about building VRWave
from the source distribution.&nbsp; I had my Java environment marginally
working in Denver, but when I moved to Dallas I must have changed something
because neither javac nor Vibe seem to be working any more.&nbsp; It may
be time to upgrade to Red Hat 5.0 anyway, so maybe I'll fix it then.
<BR>&nbsp;
<H4>
To Wave or not to Wave</H4>
The question remains:&nbsp; is VRWave a good tool for viewing and learning
about VRML?&nbsp; Yes, absolutely.&nbsp; Its still early in its development
but the tool is very stable, it didn't crash at all on any test files I
loaded (although I was only able to use the example files in the distribution).&nbsp;
Some things I'd like to see is a little better help system or at least
one that can allow me to configure where Netscape is (since I used to upgrade
often I&nbsp;didn't have it in my path, I&nbsp;have a script that knows
how to find it).&nbsp; The URL&nbsp;feature is handy but it would be nice
to be able to select from a list of URLs.&nbsp; Such a feature is more
the realm of a browser than a VRML&nbsp;viewer.&nbsp; I suppose it depends
on which VRWave wants to be in the long run.
<P>If you are just getting started with VRML&nbsp;and would just like to
look at a few examples, this is a good place to start.&nbsp; You will need
to have a working Java environment - one that can run Java applets if not
compile Java code.&nbsp; Other than that, installation is a breeze and
there are enough example files to keep you at least midly entertained until
you can write your own VRML&nbsp;worlds.
<BR>&nbsp;
<TABLE WIDTH="100%" >
<TR>
<TD VALIGN=TOP COLSPAN="4" BGCOLOR="#000000" cellpadding="0" cellspacing="0"><IMG SRC="../gx/hammel/cleardot.gif" ALT="indent" ALIGN=LEFT></TD>
</TR>
</TABLE>
&nbsp;
<TABLE WIDTH="100%" >
<TR>
<TD ALIGN=RIGHT><FONT SIZE=-2>&copy; 1998 by <A HREF="mailto:mjhammel@csn.net">Michael
J. Hammel</A>&nbsp;</FONT></TD>
</TR>
</TABLE>
&nbsp;
<!-- =============================================================
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"></A>
<TABLE>
<TR>
<TD>
<H2>
More...</H2>
<IMG SRC="../gx/hammel/musings.gif" ALT="Musings" HEIGHT=52 WIDTH=247 ALIGN=LEFT>&nbsp;</TD>
</TR>
</TABLE>
&nbsp;
<TABLE>
<TR>
<TD></TD>
</TR>
</TABLE>
<IMG SRC="../gx/hammel/cleardot.gif" ALT="indent" VSPACE=5 HEIGHT=1 WIDTH=1 ALIGN=LEFT>
<TABLE WIDTH="100%" >
<TR>
<TD ALIGN=RIGHT WIDTH="100%"><FONT SIZE=-2>&copy; 1998 <A HREF="mailto:mjhammel@csn.net">Michael
J. Hammel</A>&nbsp;</FONT></TD>
</TR>
<TR>
<TD VALIGN=TOP BGCOLOR="#000000" cellpadding="0" cellspacing="0"><IMG SRC="../gx/hammel/cleardot.gif" ALT="indent" ALIGN=LEFT></TD>
</TR>
</TABLE>
<H4>
...XeoMenu (continued)</H4>
&nbsp;<APPLET CODEBASE="." CODE="XeoMenu" WIDTH=150 HEIGHT=200><PARAM NAME=copyright VALUE="(c) 1997 Sun Microsystems Inc. All Rights Reserved."><PARAM NAME=author value="Patrick Chan. www.xeo.com"><PARAM NAME=bg-color value="206 114 28"><PARAM NAME=image VALUE="./gx/hammel/xeomenu-1.gif"><PARAM NAME=separator VALUE="|"><PARAM NAMe=newline VALUE="^"><PARAM NAME=font VALUE="Helvetica"><PARAM NAME=font-height VALUE="18"><PARAM NAME=marginh VALUE=2><PARAM NAME=marginv VALUE=2><PARAM name=fg-menu-color value="0 0 0"><PARAM name=bg-menu-color value="206 114 28"><PARAM name=fg-hi-menu-color value="232 221 18"><PARAM name=bg-hi-menu-color value="206 114 28"><!-- param name=target value="_self" --><PARAM NAME=menu0
VALUE="0 0 150 100|151 0 150 100|0 0|d|/path/to/file-1.html|What is Linux?|/path/to/file-2.html|How can I get it?|/path/to/file-3.html"><PARAM NAME=menu1 VALUE="0 101 150 100|151 101 150 100|0 101|d|/path/to/file-4.html"></APPLET>
<P>This first example shows the basic workings of XeoMenu.&nbsp; Note that
when you place the mouse over either word in the image it changes colors
and shifts slightly in position.&nbsp; The latter was originally just a
typo but I liked it the effect so much I left it in.&nbsp; The "Linux"
text also provides a drop down menu when you place your cursor over it.&nbsp;
The menu contains two simple entries.&nbsp; Moving the mouse over either
entry would take you to another page (although the links in this source
are fictitious - they don't really exist).
<P>The applet code for this first example looks like this:
<UL><B><FONT SIZE=-1>&lt;APPLET CODEBASE="." CODE="XeoMenu" WIDTH=150 HEIGHT=200></FONT></B>
<BR><B><FONT SIZE=-1>&lt;PARAM NAME=copyright VALUE="(c) 1997 Sun Microsystems
Inc.&nbsp; All Rights Reserved."></FONT></B>
<BR><B><FONT SIZE=-1>&lt;PARAM NAME=author value="Patrick Chan.&nbsp; www.xeo.com"></FONT></B>
<BR><B><FONT SIZE=-1>&lt;PARAM NAME=bg-color value="206 114 28"></FONT></B>
<BR><B><FONT SIZE=-1>&lt;PARAM NAME=image VALUE="./gx/hammel/xeomenu-1.gif"></FONT></B>
<BR><B><FONT SIZE=-1>&lt;PARAM NAME=separator VALUE="|"></FONT></B>
<BR><B><FONT SIZE=-1>&lt;PARAM NAMe=newline VALUE="^"></FONT></B>
<BR><B><FONT SIZE=-1>&lt;PARAM NAME=font VALUE="Helvetica"></FONT></B>
<BR><B><FONT SIZE=-1>&lt;PARAM NAME=font-height VALUE="18"></FONT></B>
<BR><B><FONT SIZE=-1>&lt;PARAM NAME=marginh VALUE=2></FONT></B>
<BR><B><FONT SIZE=-1>&lt;PARAM NAME=marginv VALUE=2></FONT></B>
<BR><B><FONT SIZE=-1>&lt;param name=fg-menu-color value="0 0 0"></FONT></B>
<BR><B><FONT SIZE=-1>&lt;param name=bg-menu-color value="206 114 28"></FONT></B>
<BR><B><FONT SIZE=-1>&lt;param name=fg-hi-menu-color value="232 221 18"></FONT></B>
<BR><B><FONT SIZE=-1>&lt;param name=bg-hi-menu-color value="206 114 28"></FONT></B>
<BR><B><FONT SIZE=-1>&lt;!-- param name=target value="_self" --></FONT></B>
<P><B><FONT SIZE=-1>&lt;PARAM NAME=menu0</FONT></B>
<BR><B><FONT SIZE=-1>&nbsp; VALUE="0 0 150 100|151 0 150 100|0 0|d|/path/to/file-1.html|What
is Linux?|/path/to/file-2.html|How can I get it?|/path/to/file-3.html"></FONT></B>
<P><B><FONT SIZE=-1>&lt;PARAM NAME=menu1</FONT></B>
<BR><B><FONT SIZE=-1>&nbsp;&nbsp; VALUE="0 101 150 100|151 101 150 100|0
101|d|/nav/new/index.html"></FONT></B>
<P><B><FONT SIZE=-1>&lt;/APPLET></FONT></B></UL>
We'll step through these one time to explain briefly what each line does.&nbsp;
The first line starts the applet code and establishes the current directory
(the one from which this page was taken) as the location for the applet
code.&nbsp; The CODE argument gives the name of the Java program.&nbsp;
Note that you don't have to include the ".class" extension (all Java programs,
once compiled, have a .class extension in the filename).&nbsp; The width
and height arguments give the dimensions in which the applet will live
in the page.&nbsp; Note that this code was placed right after a table,
inside the BODY section of the HTML document.&nbsp; After this line come
the set of applet parameters, each of which is specified using the HTML
PARAM tag.
<P>The next two lines give the copyright and program author, giving credit
to Sun Microsystems and Patrick Chan for this code.&nbsp; Sun paid Xeo
for its development, I believe, for use on the Java Web site.
<P>The next line gives a background color to use in the transparent regions
of the image.&nbsp; This particular example does not have any transparent
areas, however the next one does.
<P>The image to use is specified with the image parameter line.&nbsp; The
VALUE can be any valid URL.
<P>The seperator is a single character used to delimit fields in the menu
parameters.&nbsp; The menu parameters are the last two PARAM entries which
we'll cover in a moment.&nbsp; For now, just note that the seperator is
used in the VALUE argument for the menu parameters.
<BR>&nbsp;
<BR>Menu items can have multiple lines using this program.&nbsp; In order
for XeoMenu to recognize a line break, the text uses a caret (^) to denote
a newline.&nbsp; These are not used in these examples, but the caret would
be embedded in the menu text in the menu parameters.
<P>The next two lines specify the font and font height to use for the menu
text.&nbsp; According to the man page for XeoMenu there are only 3 possible
font types:&nbsp; Helvetica, TimesRoman, and Courier.&nbsp; This is probably
a limitation in the early Java class libraries, but I'm not certain of
that.
<P>Marginh and marginv are used to pad the region around the menu text
with empty space.&nbsp; The values are given in pixels.
<P>Now come the text color parameters.&nbsp; First are the foreground and
background colors to use for the text when the cursor has not been moved
over the text, ie the default text colors.&nbsp; The latter two specify
the colors to use when the cursor is placed over a menu entry.&nbsp; Note
that in the first example the background colors are the same but the foreground
colors are changed.&nbsp; This isn't a recommended method - the results
are somewhat unappealing - but it does give you an idea of how the colors
can provide variations of effects.
<P>The last line before the two menu parameteers is actually commented
out, but is given for the sake of completeness.&nbsp; This parameter is
recognized by XeoMenu as the frame to display a menu items targe URL if
it is selected.
<P>Finally, we have the two menu parameters.&nbsp; XeoMenu recognizes any
parameter prefixed with the word "menu" and suffixed with a numeric value
as a menu item.&nbsp; This parameters value field contains a set of seperator
delimited values that define the display location, contents, and URLs for
each menu.&nbsp; The first set of 4 numbers is the <I>hotspot</I>.&nbsp;
This is the region, specified by an x,y location and its width and height,
in which the mouse must enter for XeoMenu to begin handling the menu features
of the image.&nbsp; The next 4 numbers specify a secondary region of the
image to overlay on the image when the mouse enters the hotspot.&nbsp;
The next two numbers specify the offset into the image to place the overlay.&nbsp;
In this example the offsets are specified so the overlay is place over
the hotspot, blotting it out as it were.&nbsp; This is not the only way
to use this feature, since the overlay can be placed anywhere on the image.&nbsp;
Note that all of the x,y coordinates are given as pixel coordinates in
the image.
<P>After the offset comes a single character.&nbsp; This can either be
a "d" or a "u".&nbsp; The "d" is used to post menus in a downward direction
and the "u" draws them upward.&nbsp; The location of the upper left corner
for the downward menus (and the lower left corner for upperward menus)
is also the offsets specified for the overlay location (ie the two numbers
that preceeded the "d" or "u").
<P>Next comes the default URL.&nbsp; This is the URL that will be used
if the user simply clicks in the hotspot without actually using a menu.&nbsp;
After this comes the menu definitions.&nbsp; These are the text of the
menu entries paired with a URL that follows immediately after it.&nbsp;
Note that in the second menu parameter there is only one URL specified
- the default URL.&nbsp; That means that no drop down menus are displayed
when you place the mouse over the Gazette hotspot, but the overlay is still
used.
<P>In this next example, both regions of text use menus.&nbsp; One uses
an upward menu and the other uses an overlay that is not directly over
the original hotspot.&nbsp; Also, this image has a transparent region.&nbsp;
Can you guess how to create this example?&nbsp; Try it first, before looking
at the <A HREF="applet.txt">source code</A>.
<BR>&nbsp;
<BR>&nbsp;<APPLET CODEBASE="." CODE="XeoMenu" WIDTH=150 HEIGHT=200><PARAM NAME=copyright VALUE="(c) 1997 Sun Microsystems Inc. All Rights Reserved."><PARAM NAME=author value="Patrick Chan. www.xeo.com"><PARAM NAME=bg-color value="206 114 28"><PARAM NAME=image VALUE="./gx/hammel/xeomenu-2.gif"><PARAM NAME=separator VALUE="|"><PARAM NAMe=newline VALUE="^"><PARAM NAME=font VALUE="Helvetica"><PARAM NAME=font-height VALUE="14"><PARAM NAME=marginh VALUE=2><PARAM NAME=marginv VALUE=2><PARAM name=fg-menu-color value="0 0 0"><PARAM name=bg-menu-color value="206 114 28"><PARAM name=fg-hi-menu-color value="232 221 18"><PARAM name=bg-hi-menu-color value="206 114 28"><!-- param name=target value="_self" --><PARAM NAME=menu0 VALUE="0 0 150 100|151 0 150 100|0 0|u|/path/to/file-1.html|What is Linux?|/path/to/file-2.html|How can I get it?|/path/to/file-3.html"><PARAM NAME=menu1 VALUE="0 101 150 100|151 101 150 100|0 70|d|/path/to/file-4.html|To Err is Human^To Forgive, Devine|/path/to/file-5.html|I think|/path/to/file-6.html"></APPLET>
<P><A HREF="./gm.html#xeomenu-summary">Back to the main Muse page.</A>
<BR>&nbsp;
<TABLE WIDTH="100%" >
<TR>
<TD VALIGN=TOP COLSPAN="4" BGCOLOR="#000000" cellpadding="0" cellspacing="0"><IMG SRC="../gx/hammel/cleardot.gif" ALT="indent" ALIGN=LEFT></TD>
</TR>
</TABLE>
&nbsp;
<TABLE WIDTH="100%" >
<TR>
<TD ALIGN=RIGHT><FONT SIZE=-2>&copy; 1998 by <A HREF="mailto:mjhammel@csn.net">Michael
J. Hammel</A>&nbsp;</FONT></TD>
</TR>
</TABLE>
&nbsp;
<H4>
"Linux Gazette...<I>making Linux just a little more fun!</I>"
</H4>
<P> <HR> <P>
<!--===================================================================-->
<A NAME="tex2html3" HREF="./kapok/node1.html"><IMG WIDTH=37 HEIGHT=24
ALIGN=BOTTOM ALT="next"
SRC="http://wwwcn.cern.ch/icons/next_motif.gif"></A> <IMG WIDTH=26
HEIGHT=24 ALIGN=BOTTOM ALT="up"
SRC="http://wwwcn.cern.ch/icons/up_motif_gr.gif"> <IMG WIDTH=63 HEIGHT=24
ALIGN=BOTTOM ALT="previous"
SRC="http://wwwcn.cern.ch/icons/previous_motif.gif"> <BR>
<B> Next:</B> <A NAME="tex2html4" HREF="./kapok/node1.html">Characteristics and
chipset</A>
<BR> <P>
<b>Linux on a Kapok 7200</b> <BR> 4.2.98 version 1.0
<P>
<P>
Alessandro Usseglio Viretta <BR> Lab for EM 1 <BR>
Schmelzbergstrasse 7, CH-8092 Zurich
<BR> e-mail: <A HREF="mailto:usseglio@biol.ethz.ch">usseglio@biol.ethz.ch</A>
<BR> Fax + 41 1 6321103
<P>
<H3 CLASS=ABSTRACT>Abstract:</H3>
<P CLASS=ABSTRACT>The Kapok 7200 is a portable computer, Intel-based,
manufactured by
Kapok - <i>http://www.kapok.com.tw</i> - in Taiwan. It is sold under a
variety of names is USA and Europe. BSI
<i>http://www.bsicomputer.com</i>,
ATC <i>http://www.at-computers.com</i>, NewChip
<i>http://www.newchip.it</i>,
AJP <i>http://www.ajp.co.uk</i>, JET <i>http://www.jet.ch</i>,
A&amp;O <i>http://www.aocomputer.com</i>, Computer Direct <i>
http://www.direct.ch</i>, Gericom <i>http://www.gericom.com</i>, Pro
Star<i> http://www.pro-star.com</i>, Megashop <i>http://www.megashop.ch</i>
are just a few vendors of this computer. It's a bulky and heavy
computer, but it's provided with a big nice TFT screen - up to 14.1&quot;
-
and a easily upgradable Pentium MMX processor. It is usually
delivered with Windows 95 already installed. The aim of this
document is to explain
how to install Linux on such a machine. If you want to keep Windows,
please refer to the HOWTOs available, for example, at
<i>http://sunsite.unc.edu/pub/Linux/docs/</i>. This document is
aimed to absolute beginners and is not intended to provide a deep
insight into the Linux operating system. After reading it, the newby
should be ready to successfully install a RedHat Linux system on
his/her laptop and start working with it.
</P><P>
<P>
<BR> <HR>
<UL><A NAME="CHILD_LINKS">&#160;</A>
<LI> <A NAME="tex2html5"
HREF="./kapok/node1.html#SECTION00010000000000000000">Characteristics and
chipset</A>
<LI> <A NAME="tex2html6"
HREF="./kapok/node2.html#SECTION00020000000000000000">Installing Linux</A>
<UL>
<LI> <A NAME="tex2html7"
HREF="./kapok/node3.html#SECTION00021000000000000000">Where to get RedHat Linux</A>
<LI> <A NAME="tex2html8"
HREF="./kapok/node4.html#SECTION00022000000000000000">Partitions</A>
<LI> <A NAME="tex2html9"
HREF="./kapok/node5.html#SECTION00023000000000000000">Which packages?</A>
</UL>
<LI> <A NAME="tex2html10" HREF="./kapok/node6.html#SECTION00030000000000000000">X
Window</A>
<UL>
<LI> <A NAME="tex2html11"
HREF="./kapok/node7.html#SECTION00031000000000000000">XF86Config</A>
<LI> <A NAME="tex2html12"
HREF="./kapok/node8.html#SECTION00032000000000000000">Which window manager?</A>
</UL>
<LI> <A NAME="tex2html13"
HREF="./kapok/node9.html#SECTION00040000000000000000">XDM</A>
<LI> <A NAME="tex2html14"
HREF="./kapok/node10.html#SECTION00050000000000000000">PCMCIA</A>
<LI> <A NAME="tex2html15"
HREF="./kapok/node11.html#SECTION00060000000000000000">Networking</A>
<UL>
<LI> <A NAME="tex2html16"
HREF="./kapok/node12.html#SECTION00061000000000000000">Ethernet</A>
<LI> <A NAME="tex2html17"
HREF="./kapok/node13.html#SECTION00062000000000000000">PPP</A>
</UL>
<LI> <A NAME="tex2html18"
HREF="./kapok/node14.html#SECTION00070000000000000000">Kernel</A>
<LI> <A NAME="tex2html19"
HREF="./kapok/node15.html#SECTION00080000000000000000">Copyright notice and
disclaimer</A>
<LI> <A NAME="tex2html20" HREF="./kapok/node16.html#SECTION00090000000000000000">
About this document ... </A>
</UL>
<!--===================================================================-->
<P> <hr> <P>
<center><H5>Copyright &copy; 1998, Alessandro Usseglio Viretta <BR>
Published in Issue 26 of <i>Linux Gazette</i>, March 1998</H5></center>
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<center>
<H2>Low Cost Macintosh-Linux Networking at Home</H2>
<H4>by <A HREF="mailto:rld@erols.com">Dr. Richard L. Dubs</A></H4>
</center>
<P> <HR> <P>
<H3>Contents:</H3>
<ul>
<li><a HREF="./dubs.html#intro">I. Introduction</A>
<li><a HREF="./dubs.html#network">II. Network Overview</A>
<li><a HREF="./dubs.html#hardware">III. Network Hardware and Software</a>
<li><a HREF="./dubs.html#setup">IV. Setting Up</A>
<li><a HREF="./dubs.html#oper">V. Operations</A>
<li><a HREF="./dubs.html#final">VI. Final Comments</A>
</ul>
<A name="intro"></A>
<H3>I. Introduction</H3>
<P>
Only one hour after I taught my wife, Lois, how to access the Internet
with our Macintosh Quadra 605, I knew that my dream of having a Linux-based
home network would be realized. Surely, I reasoned, it would now be
unacceptable for me to "hog" our Internet connection and prevent Lois from
tracking down Star Trek Collector's Cards online. Fortunately I had used
Linux IP Masquerading in a previous life as a LAN administrator and knew
that a Linux solution would allow us both to be on the Internet at the same
time with only a single modem connection and IP address from our Internet
Service Provider.
<P>
There were a couple of constraints, however. First, there was no space in
my family room for another computer; any additional system would have to be
set up in the basement. Second, our Mac did not have an Ethernet card, nor
was I inclined to pull Ethernet cable through my house. Third, any
solution would have to be achieved on a shoestring budget (Did you hear the
one about the guy whose wife had her credit cards stolen, and the guy
didn't report it because the thief spent less than the wife?)
<P>
This article describes the Linux networking solution I came up with - it
consists of my Mac, a Linux Box and a low cost dos-based router. It is not
"state of the art", but it is a solution that works within the constraints
I imposed, it is relatively simple, and it is one that many people haven't
heard about before. As you will see, it heavily leverages software and
information available on the Internet. Mac, DOS, and Linux users will all
find something of interest in the material presented herein.
<P>
The remainder of this article is organized as follows: Section II
presents an overview of my home network; Section III describes the network
hardware and software; Section IV addresses setting up; Section V describes
operations; and Section VI presents final comments, including things to
try.
<A name="network"></A>
<H3>II. Network Overview</H3>
<P>
<center><img src="./gx/dubs/schematic.gif"></center>
<P>
Figure 1 presents a schematic of my home network. My Macintosh (family
room) has connectivity to my Linux box (basement) through a low cost
dos-based router (also basement). The Macintosh-router segment is
LocalTalk and the router-Linux box segment is Ethernet (thinnet). The
Linux box provides the dialup PPP connection to my Internet Service
Provider (ISP) and runs IP Masquerading which allows the Macintosh and the
Linux box to use the Internet at the same time through the single dialup
connection.
<A name="hardware"></A>
<H3>III. Network Hardware and Software</H3>
<H4>LocalTalk</H4>
<P>
LocalTalk seemed the best way to establish connectivity between my family
room (Mac) and my basement (PC's) for two reasons:
<ul>
<li>LocalTalk support is already built into every Macintosh. I didn't have
to buy additional hardware for my Mac.
<li>A LocalTalk network can be run over ordinary phone lines. I used the
free pair of wires in the existing telephone line in my house for the
localtalk segment of my LAN.
</ul>
<P>
Some people might say that LocalTalk, at 230 KB/sec is too slow to be
useful for networking. (Ethernet, in comparison, is 10MB/sec). However, my
modem connection is only 14.4 KB/sec (57.6 KB/sec maximum throughput)
making LocalTalk seem more than adequate.
<H4>Router</H4>
<P>
Having a LocalTalk connection from my Mac to my basement still didn't help
me connect to my Linux box. Linux does offer AppleTalk support, but it
does not yet offer support for LocalTalk (although I understand the hooks
for LocalTalk are now built into the AppleTalk code).
<H4>Figure 1. Schematic of My Mac-Linux Home Network</H4>
<P>
That's where the free router software, PCROUTE by Vance Morrison, comes
in. PCROUTE is dos-based software available on the Internet (PCRTE224.ZIP
at http://www.nova.edu/Inter-Links/simtel/network.html) that routes TCP/IP
packets between LocalTalk and Ethernet networks. PCROUTE can run on a PC
XT or better ( and it doesn't require an AppleTalk - IP Gateway like the
LocalTalk packet driver-based routers such as KA9Q). Once PCROUTE is set
up correctly, you don't even need a keyboard or monitor if your computer
can boot without them. I run PCROUTE on an old 386 PC with 1Meg of Ram and
a 5.25 inch floppy drive.
<P>
PCROUTE comes with excellent instructions on how to compile and configure
it as a LocalTalk/Ethernet router. Of course the router needs both a
LocalTalk PC card and an Ethernet card. The latter I already had and the
former I bought for $27 + shipping from MacResource Computers, a
Texas-based company I found on the Internet
(<A
HREF="http://www.mac-resource.com/mac-resource/">http://www.mac-resource.com/mac-resource/</A>).
<P>
Some more comments about the LocalTalk connection between my Mac and the
router. To use phone lines for LocalTalk, both my Mac and the router
required LocalTalk/RJ-11 adapters. The 8 pin mini-din variety is available
at any computer superstore, however, the LocalTalk PC board required the
older 9 pin variety. Those are easy enough to find for sale on the
Internet, but I found the circuit itself on the Internet instead
(http://www.jura2.uni-hamburg.de/~kai/LAM_HTME/cap1.htm)! It turns out
that you can build the 8 or 9 pin variety with only 5 resistors, 2
capacitors, and some miscellaneous parts - and it all fits in a 35mm film
canister! I built one for my router and it works great. (One word of
caution - the pinouts for the 9 pin adapter or left/right backward in the
figure provided with the circuit.)
<P>
I have a single phone line in my house; it uses the inner red and green
wires of the modular phone plug for the telephone connection. The outer
black and yellow wires are available for LocalTalk. Fortunately,
LocalTalk/RJ-11 adapters are already wired to use the outer wires.
<H4>Linux</H4>
<P>
My Linux box is a 486DX33 PC with 16Megs of Ram, a 270MB hard disk, and a
14.4 baud Modem. It uses a thinnet Ethernet connection to the router. The
only unusual part of installing Linux was that my 486 does not have a
CD-ROM drive. To load the Linux software, I decided I needed to get the
software on the DOS partition of my 486 so I could install Linux from
there.
<P>
To accomplish this I temporarily installed the LocalTalk PC card in the
486 and loaded the software that came with the card. The software allows
you to mount Macintosh folders as letter drives (e.g. f:) on your PC. I
simply copied the Linux installation software off the CD-ROM into a folder
on my Macintosh hard disk, mounted that folder over the LocalTalk network
as drive f: on the 486, and used XCOPY to move all the LINUX software to my
486 (e.g. XCOPY f:*.* c: /s /e).
<A name="setup"></A>
<H3>IV. Setting Up</H3>
<P>
I followed RFC 1597, which allocates certain IP addresses for private
networks, and internally assigned 192.168.1.x for my LocalTalk segment and
192.168.2.x for my Ethernet segment. In the next three sections, I provide
specific instructions for configuring the network.
<H4>Macintosh Setup</H4>
<P>
The Macintosh setup is straightforward. Select MacTCP from the control
panel. In the first MACTCP window, select the "More" button. In the second
window, set the server to "Manual" and the gateway IP to 192.168.1.1 (This
is the IP address for the router's LocalTalk PC card). I leave the DNS
servers the same as I use to access the Internet directly with my Mac's
modem.
<P>
Click "OK" to return to the first MacTCP screen. On the first screen,
change the Mac's IP address to 192.168.1.2 and select the LocalTalk icon.
Make sure that LocalTalk is turned on in the Chooser.
<H4>Router Setup</H4>
<P>
PCROUTE comes with excellent documentation which I will not repeat here.
I set up the LocalTalk interface with an IP address of 192.168.1.1 and the
Ethernet interface with an IP address of 192.168.2.1. For the Ethernet
interface I have successfully compiled and run two different configurations
of PCROUTE, one that uses a direct interface to an 8 bit WD8003 Ethernet
card and one that uses an Ethernet packet driver interface. The nice
feature of the packet driver interface is that it allows you to use any
Ethernet card for which a packet driver exists. I have successfully used
PCROUTE with both the WD8003 card and a 16-bit NE2000 compatible card using
packet drivers.
<P>
In the router, I set a static default route to 192.168.2.2 (the Linux box)
so that any IP address not recognized by the router (e.g. www sites from my
Mac intended for the Internet) will be routed by default to the Linux box.
<P>
A neat feature of PCROUTE is that it allows you to designate the Linux box
as a syslogd host that logs status messages from the router. When the
router starts up, and approximately every 15 minutes thereafter, the router
sends the Linux box a "Router is up" message that is recorded in a file on
the Linux box that you specify.
<H4>Linux Setup</H4>
<P>
I set the IP address for the Linux Ethernet interface to 192.168.2.2 and
designated the router (192.168.2.1) as the gateway for packets addressed to
the LocalTalk segment (192.168.1.x).
<P>
To log syslog messages from the router, edit the /etc/syslog.conf file as
described in the PCROUTE documentation. Then reboot Linux or type kill
-HUP &lt;pid&gt;, where pid is the syslogd process id obtained by typing ps -x.
<H4>IP Masquerading</H4>
<P>
As stated earlier, I use IP Masquerading to give my Mac and Linux box
simultaneous access to the Internet through a single PPP connection to my
ISP. However, because I use Linux 1.2.13, the IP Masquerading capability
has to be built into the kernel as a patch. Fortunately, IP Masquerading
comes with excellent instructions for applying the patch.
<P>
To configure IP masquerading, I use:
<pre>
ipfw a m all from 192.168.2.0/24 to 0.0.0.0/0
ipfw a m all from 192.168.1.0/24 to 0.0.0.0/0
</pre>
<P>
These steps will automatically masquerade my Mac and any future computer I
add to either my LocalTalk segment or my Ethernet segment. If you don't
want to retype these lines each time you reboot your computer, add the
steps to one of the startup scripts executed from the /etc/rc.d
directory.
<P>
I will not describe setting up a PPP connection from my Linux box to my
ISP; good instructions are already provided in the Linux How-To documents.
When the PPP link is up and running and IP Masquerading is set up as
described, my routing table (obtained by typing "route -n") looks like:
<pre>
Destination Gateway Genmask Iface
207.96.96.102 * 255.255.255.255 ppp0
192.168.2.0 * 255.255.255.0 eth0
192.168.1.0 192.168.2.1 255.255.255.0 eth0
127.0.0.0 * 255.0.0.0 lo
default 207.96.96.102 * ppp0
</pre>
<A name="oper"></A>
<H3>V. Operations</H3>
<P>
My setup works great! I can initiate a PPP connection to my ISP by
logging into my Linux box, either by walking down the basement, or
telnetting to the Linux box from my Mac. Best of all, thanks to IP
Masquerading, my wife and I can now both use the Internet at the same time!
<P>
With my new LAN setup, my Internet programs (e.g. my web browser) run
slightly faster now because my Mac no longer has to simultaneously maintain
a modem connection and run MacPPP. Further, when I have to reboot my Mac
(yes, it does happen occasionally with Macs) I don't have to redial my ISP
because the connection is maintained by my Linux box; as soon as I reboot,
I'm back online.
<A name="final"></A>
<H3>VI. Final Comments</H3>
<H4>Things to Try</H4>
<P>
I have not tried to optimize the performance of my Mac-Linux LAN. However,
since Ethernet packets can be almost 3 times larger than LocalTalk packets,
one thing to try is to move the burden of reducing the packet size from the
router to the Linux box by reducing the MTU parameter of the Linux Ethernet
interface. (For example, to change the MTU size to 500, type "ifconfig
eth0 mtu 500.") Another interesting thing to try is IRQTUNE which lets you
give the serial port on the Linux box higher processing priority so that it
has less chance of dropping packets (http://www.best.com/~cae/irqtune). I
have not tried IRQTUNE yet, but it might be a good thing to run for anyone
using a modem with a Linux box.
<P>
One of the things I'd like to try is accessing my Linux box using X-server
software on my Mac. I'll have to make sure that the X-server software can
run over LocalTalk.
<H4>Summary</H4>
<P>
This article has described a low cost way of creating a Mac - Linux
network at home. I hope that Mac, DOS, and Linux users have all found
something of interest in the setup I've described.
<P>
I would be happy to hear from anyone with comments or questions.
<!--===================================================================-->
<P> <hr> <P>
<center><H5>Copyright &copy; 1998, Dr. Richard L. Dubs <BR>
Published in Issue 26 of <i>Linux Gazette</i>, March 1998</H5></center>
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<center>
<H1>Tcd and Gtcd</H1>
<h4>by <a href="mailto: layers@marktwain.net">Larry Ayers</a></h4>
</center>
<P> <HR> <P>
<center><h3>Introduction</h3></center>
<p>CD-players for Linux abound these days, with both curses-based console
programs and X programs available in a variety of degrees of usefulness,
complexity, and polish. There are even command-line players, though with the
current CDROM drives (with their built-in controls) a player is no longer
strictly necessary. The main advantage of using a dedicated CD-player program
is the possibility of using a database containing titles and track names,
as well as play-lists, auto-repeating and other user conveniences.
<p>Xmcd is one of the more popular X-windows players; it's a freely
available program but does require the proprietary Motif libs for compilation
from source, though statically-linked binaries are available. One reason for
its popularity is the internet database of CD titles and tracklists which is
accessible from within the program. This database is remarkably complete, and
once you start using it only the most obscure titles should ever have to be
entered manually. This database project has really mushroomed; originally Ti
Kan (author of Xmcd) created the database format for use in his program, and
distributed database files made up of user contributions. The files began to
become excessively large and cumbersome, so the idea of making them
directly accessible via the internet arose. Ti Kan recruited Steve Scherf to
write a protocol which would make possible quick retrieval of individual
queries, and Steve found sites which agreed to become servers. There are now
CDDB servers distributed across the planet, and the databases are even
accessible from behind firewalls from many HTTP servers. Information on
incorporating the protocol into a CD-player program is available from
<a href="http://www.cddb.com">the cddb website</a>; this material is freely
available, and assistance is offered for freeware and shareware developers.
<p>Unfortunately, I never have been able to get Xmcd to work consistently on
my system; there is something in the way my ATAPI drive works which causes
problems. Xmcd was originally written with SCSI drives in mind, and although
ATAPI IDE drive support has been added it didn't seem to care for my drive's
peculiarities.
<center><h3>Tcd and Gtcd</h3></center>
<p>I've been using Tim Gerla's simple but useful console-mode player tcd for
several months, and have become quite adept at quickly typing in disc and
track information. Recently Tim introduced a new version. and after unpacking
it I was surprised and pleased to see that not only had he produced a
GTK-based X version, but the program now supports the CDDB protocol. So one
day I was on the internet, downloading some beta software, and started up the
new tcd version. I was playing a disc which I hadn't entered into the
program's database, and I happened to see a notice on the screen which said
"[D] Download CDDB data". I gave it a try, thinking that it would probably
take awhile, and that the particular CD I was playing probably wasn't even
listed. Within two seconds the title and track data was displayed on the
screen, which startled and impressed me.
<p>This newly released version, 2.0b, is a beta, though I haven't encountered
any but the most minor bugs. The GTK version doubtless will be revised, as
GTK is still under active development. Here's a screenshot of the interface:
<br>
<center><p><img alt="Gtcd" src="./gx/ayers/gtcd.gif"></center>
<p>It's a nice-looking interface, with that distinctive GTK look made familiar
by the Gimp. When the CDDB button is clicked a window opens with the default
server and port displayed in entry fields, which can then be edited depending
on your location. A convenient drop-down menu of track titles (invoked by
clicking the <em>Goto</em> button) is a feature not found on many players.
<p>Most of tcd's features can be found on other X-windows players, though the
only others which are CDDB-enabled (as far as I know) are Xmcd and the KDE
CD-player Kscd, written by Johannes Wuebben. The last-mentioned is a very
usable and well-done application, but requires the KDE and Qt libraries in
order to function. Gtcd only needs gtk+-0.99.3, which is also needed by the
Gimp.
<p>An unusual feature is the existence of both console and X executables which
share the same features, configuration, and database. I use X about
two-thirds of the time, shutting it down when I'm compiling large applications
or just writing in an editor, and it's nice to be able to use the same
CD-player in each environment.
<center><h3>Availability</h3></center>
<p>As I write this, the source and binary distributions are still in the
incoming directory at <a href="ftp://sunsite.unc.edu/pub/Linux/Incoming"
>Sunsite</a>, with the filenames prefixed by tcd-2.0b; an alternate site is
<a href="http://flow.ml.org/tcd/">here</a>.
<!--===================================================================-->
<P> <hr> <P>
<center><H5>Copyright &copy; 1998, Larry Ayers <BR>
Published in Issue 26 of <i>Linux Gazette</i>, March 1998</H5></center>
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<center>
<h1>Setting up Your In-Home (or In-Office) Network</h1>
<H4>By <a href="mailto:tkunz@redeemer.rutgers.edu">Tom Kunz</a></H4>
</center>
<P> <HR> <P>
<H3>Contents:</H3>
<ul>
<li><a HREF="./kunz.html#intro">What Does This Article Cover?</A>
<li><a HREF="./kunz.html#begin">Before You Begin - Have a Working
Network!</A>
<li><a HREF="./kunz.html#config">Configuring Your Local Network</A>
<li><a HREF="./kunz.html#diald">Installing diald</A>
<li><a HREF="./kunz.html#pppd">Installing pppd</A>
<li><a HREF="./kunz.html#kernel">Kernel Configuration</A>
<li><a HREF="./kunz.html#fire">Configuring IP Forwarding Firewall</A>
<li><a HREF="./kunz.html#pppd2">Configuring pppd</A>
<li><a HREF="./kunz.html#diald2">Configuring diald</A>
<li><a HREF="./kunz.html#time">Setting Time-Outs and Other Options</A>
<li><a HREF="./kunz.html#app">Application Notes</A>
<li><a HREF="./kunz.html#final">Conclusion</A>
</ul>
<A name="intro"></A>
<h3>What Does This Article Cover?</h3><br>
<P>
Well, this article covers a couple of topics that you've probably seen
discussed before in <i>Linux Gazette</i> and/or <i>Linux Journal</i>.
Let's say you have 2 or more computers, maybe in an office, maybe at
home, and you want to have one of them be the "gateway" for the
other(s). If your ISP charges by the minute (or in 5/10/15 minute
increments), which many of them do for corporate accounts, then you
don't want to spend excessive amounts of time on the line to your ISP.
You also don't want to risk <b><i>forgetting</i></b> that you are
connected and running up a bill while doing nothing! So what you want
is a way to get your local network onto and off of the Internet with
ease, and with a minimum of extraneous cost. This includes
demand-dialing, IP forwarding, IP Masquerading, PPP configuration, and
some basics of networking. Sounds like a lot (and believe me, it
<b><i>can be</i></b>!), but it's not so bad when you find out that,
for
the most part, you don't necessarily <i>need</i> all the power and
flexibility that the packages involved in this setup have.<p>
Please note that while I will be detailing how to set up your Internet
gateway in Linux, that does not imply that your entire network needs
to be running Linux. You can have one Linux box acting as the
gateway, while the rest of the network is a mix of other platforms.
You can have any kind of hardware and software on the network,
provided that the systems have a TCP/IP stack. Any mix of DOS, Mac,
Win95, or unix workstation can be applied to a network configured in
this way.<p>
This kind of arrangement is extremely useful for a number of reasons.
If WWW browsers are going to be used heavily, this kind of network is
ideal. WWW browsers open transient TCP connections for operation,
which download chunks of information in spurts, usually not remaining
connected for more than a few seconds. While someone reads a web
page, the browser generates no (or very little) network traffic, thus
leaving the connection idle, and allowing someone else to share the
unused bandwidth to full potential. Another reason for installing
this kind of arrangement is so that users don't tie up valuable phone
lines for extended periods. Recently, I installed a similar
arrangement for a small company whose employees were frequently on the
Internet from their PC's, each using their own phone line at their
desk. Of the few and costly phone lines they had, usually half of
them were doing dial-up connections, while the other half could handle
voice calls. By the arrangement that I prescribe here, they limited
it to one phone line, and everybody was able to access the Internet
while using the phone line at their desk for voice.<p>
To describe what I've done here, I'm working from the reference frame
of having installed a fresh copy of Red Hat 4.2, with the option of
installing everything set. From what I've seen, 5.0 isn't incredibly
different (for this stuff, anyway), and I'll also be pointing out the
differences between setting this up on Red Hat and setting this up on
Slackware 3.3.<p>
<A name="begin"></A>
<h3>Before You Begin - Have a Working Network!</h3><br>
<P>
First and foremost, I would recommend some other documents for your
perusal before engaging in setting up a working LAN. These would be:
<ul>
<li><a href="http://www.linuxresources.com/LDP/LDP/nag/nag.html">The
Network Administrator's Guide</a>
<li><a
href="http://www.linuxresources.com/LDP/LDP/sag/index.html">Linux
System Administrator's Guide</a>
<li><a
href="http://www.linuxresources.com/LDP/HOWTO/NET-3-HOWTO.html">NET-3-HOWTO,
Linux Networking</a>
<li><a
href="http://www.linuxresources.com/LDP/HOWTO/Ethernet-HOWTO.html">Ethernet-HOWTO,
the details about ethernet hardware for Linux</a>
</ul>
In order to set up a home or office network with a dial-up gateway,
you first need to have a local area network (LAN) working correctly.
I would recommend you read over the above documents in some detail as
you attempt to get your network going. The exact type of network card
you use is not important to the discussion of the text, but if asked,
I would recommend ISA cards, either 16- or 8-bit, in order to cut your
teeth on networking. They provide the least hassles and have been
well supported by Linux for years. My personal favorites are the
SMC/WD 80*3 cards, but virtually all legacy ISA cards (non-PnP,
jumper-configurable cards) should work. See the documentation listed
above for exact details on making your network run.<p>
<A name="config"></A>
<h3>Configuring Your Local Network</h3><br>
<P>
I will be using the term "Linux gateway" or "gateway" to denote the
machine on your network which will be running Linux and actually have
the modem and will be performing the connections to the outside world
for your network.<p>
Networks for small offices or within a home are generally not in
registered domains. If you are setting up a connection for an office
which <i>is</i> in a registered domain with an IP address which is
part of the Internet (ie, not one of the reserved network numbers for
private use), then you will need to configure your network according
to that registered domain and IP address block which you have been
allocated by InterNIC. If you don't know what I'm talking about, then
you want to use one of the "reserved" network numbers that are set
aside for private usage. The network number which I will use will be
"192.168.1.0", which I have configured for my home usage. Because
it's reserved, I know that all my packets will not conflict with
anyone on the Internet, since all packets destined for reserved
addresses are dropped by your ISP's routers, and the main backbone
routers on the Internet.<p>
Note that the steps I describe here are often done in parallel with
the previous section on "Have a Working Network". Once you've
selected a reserved IP address block for your network, you need to
configure your hardware to be recognized and give the appropriate
parameters to the software. I recommend setting the gateway's address
to the ".1" node number of your network. It's not a law, but it's
commonly accepted and easy to remember. For example, if you are using
192.168.1.0 as your network, then 192.168.1.1 will be your Linux
gateway. Then have the other systems on the network numbered as
192.168.1.2 through 192.168.1.254. Some administrators like to have
their nameserver for the LAN set up as ".254", but if you only have a
few machines on your network, you're not likely to need or want a
nameserver.<p>
Selecting a domain name doesn't deserve a huge amount of thought.
It's just a matter of coming up with something that is easy to
remember, describes your network, and will not conflict with any
registered domain names. The extensions of ".com", ".org", and
".edu", as well as country abbreviations (".de", ".uk", ".au", etc.)
are off-limits. Just don't use anything that looks like a typical
address, and you'll be ok. For example, my local network at home is
the domain of "kunz.home". There's no domain out there belonging to
".home", so it's OK. Or if you want to set up an office network for
"ACME Inc.", then you might try "acme.office" as your domain name.<p>
The network parameters can be set up in Linux either while performing
the initial installation or after the installation has been done. If
you decide that you would like to have your gateway named "linux-gw",
and that you want your domain to be "smith.home", you will not have
any conflicts with names outside of your network. If you are using
192.168.1.0 as your network number, then the parameters for networking
should look like this:
<ul>
<li>Host Name: linux-gw
<li>Domain Name: smith.home
<li>IP Address: 192.168.1.1
<li>Netmask: 255.255.255.0
<li>Broadcast: 192.168.1.255
<li>Default Gateway:
<li>Primary Nameserver: (IP address of your ISP's primary nameserver)
<li>Secondary Nameserver: (IP address of your ISP's secondary
nameserver)
<li>Tertiary Nameserver: (IP address of your ISP's tertiary
nameserver)
</ul>
Note: Not all TCP/IP implementations will ask for or be configurable
for more than one or two nameservers. Just ignore the "secondary" and
"tertiary" fields if that's the case.<p>
Also, notice that it's important to leave the default gateway
<i><b>empty!</b></i> The routing tables will be modified by diald,
which will be discussed later.<p>
On "linux-gw", you should make/edit the /etc/hosts file. It should
contain the IP addresses and names of all the machines on the
network. Let's say you will have 4 machines on the network besides
the Linux gateway. You might, conceivably, have an /etc/hosts file
that looks something like this:
<pre>
127.0.0.1 localhost localhost.localdomain
192.168.1.1 linux-gw.smith.home linux-gw
192.168.1.2 winchester.smith.home winchester
192.168.1.3 ruger.smith.home ruger
192.168.1.4 browning.smith.home browning
192.168.1.5 mossberg.smith.home mossberg
</pre>
By doing this, the Linux gateway knows the names of all the machines
on the network. This should also be done on any unix workstations or
other Linux machines you have on the network. On Slackware
installations, you'll need to edit this by hand. On Red Hat, you can
use the "netcfg" program under X to modify the "Hosts" entry.<p>
On each of the other machines in the network, you will need to
configure their parameters as follows. Be sure not to duplicate IP
addresses between different machines! The following sample entry is
for a client on the "smith.home" network named "winchester".
<ul>
<li>Host Name: winchester
<li>Domain Name: smith.home
<li>IP Address: 192.168.1.2
<li>Netmask: 255.255.255.0
<li>Broadcast: 192.168.1.255
<li>Default Gateway: 192.168.1.1
<li>Primary Nameserver: (IP address of your ISP's primary nameserver)
<li>Secondary Nameserver: (IP address of your ISP's secondary
nameserver)
<li>Tertiary Nameserver: (IP address of your ISP's tertiary
nameserver)
</ul>
Now, notice basically only one major change: the default gateway.
When any of the machines on the network send out packets, we want them
to route them through 192.168.1.1, which is your Linux gateway. As
the gateway for the rest of the network, Linux will decide where
packets get sent. You should configure all the machines on the
network with the above paramters, changing only the host name and the
IP address for each. Any TCP/IP-capable platform should have the
provisions to be configured as above, save only possibly for the
secondary and tertiary nameserver portion. Note that it's also quite
possible that your ISP will only provide one or two nameservers, and
that the third is unlikely to be filled, most of the time.<p>
If you are configuring a Slackware Linux machine as your gateway
<i>after</i> installation, the appropriate way to change the network
parameters is to run the program "netconfig" as root. You will be
prompted for the network parameters one at a time, and should follow
the "linux-gw" listing above. Under Red Hat, you should run the
"netcfg" program from X while root. This provides a graphical tool
for doing the same thing. Running "control-panel" as root in Red Hat
provides an X front-end to many of the administrative tasks, including
networking.<p>
By the time you get this far, you should have a working network, where
you can telnet from any of the machines on your network into the Linux
gateway.<p>
<A name="diald"></A>
<h3>Installing diald</h3><br>
<P>
The package that we will be using for performing the automatic
dialling is "diald". This assumes that you have a modem which Linux
is already aware of. If not, you need to consult your installation
documentation and the incredibly useful <a
href="http://www.linuxresources.com/LDP/linux.html">Linux
Resources</a> page<p>
Once you can verify that your modem is working ok and is recognized by
Linux correctly, we can configure diald to do the work for us. As a
note, I would like to say that I've had the least problems with
external modems and with non-PnP modems. These days, it's hard (if
possible at all) to find a non-PnP internal modem. If you absolutely
<i>have</i> to use a PnP modem, then I recommend getting the <a
href="http://www.sunsite.unc.edu/pub/Linux/system/hardware/isapnptools-1.11.tgz">isapnptools
package</a>
for initializing PnP configuration.<p>
First, you need to obtain and install diald. If not already installed
on your system, it's possible to obtain the <a
href="http://www.sunsite.unc.edu/pub/Linux/system/network/serial/diald-0.16.tar.gz">
code</a> from Sunsite. If you have Red Hat, you can find the binary
distribution in RPM format on your Red Hat 4.2 CDROM. It is located
in /[mountpoint]/RHSCont/i386/diald-0.16-3.i386.rpm. The file
diald-config-0.1-1.i386.rpm is found in the same directory, and I
recommend you install it, since it contains some sample configurations
that may be useful to you. Under Red Hat 5.0, I was unable to find it
on the 2-CDROM distribution set from Red Hat, so the latest version of
diald should be <a
href="http://www.sunsite.unc.edu/pub/Linux/system/network/serial/diald-0.16.tar.gz">
downloaded from Sunsite</a>. The same goes for Slackware. Download
the pacakge and follow the build instructions included. [LG HTML
note: if you find those links are broken by the time you read this,
you should be able to browse <a
href="http://www.sunsite.unc.edu/pub/Linux/system/network/serial/">
http://www.sunsite.unc.edu/pub/Linux/system/network/serial/</a> to
find the current version of diald]<p>
<A name="pppd"></A>
<h3>Installing pppd</h3>
<P>
Once you have diald installed, we need to install pppd. This comes up
in both Slackware and Red Hat 4.2/5.0 as packages that are selected
for installation if you install everything. If it is not installed,
it can be found on your Red Hat 4.2 CD in
/[mountpoint]/RedHat/RPMS/ppp-2.2.0f-3.i386.rpm. If you have RedHat
5.0, you will find it on the first CD of the set, in
/[mountpoint]/RedHat/RPMS/ppp-2.2.0f-5.i386.rpm. Slackware contains
the ppp.tgz package at or around floppy N3 or
/[mountpoint]/slakware/n3. If you don't have it installed on your
Linux gateway already, you may need to <a
href="http://www.sunsite.unc.edu/pub/Linux/system/network/serial/ppp/ppp-2.2.0g.tar.gz">download</a>
the source for it from Sunsite. Basically, just follow the build
instructions and install it via the Makefile.
<A name="kernel"></A>
<h3>Kernel Configuration</h3>
<P>
Now you have diald and pppd installed, but you may not have any
support for IP Masquerading, which is an absolute MUST for this kind
of networking scheme. If you are using a stock Red Hat 5.0 kernel,
you will be fine, as just about everything is compiled as a module.
IP forwarding will be provided on-demand by kernel module loader, as
long as you have modified /etc/sysconfig/network (see "Configuring IP
Forwarding Firewall", below). If you're using a stock kernel that
came with Slackware, you probably don't have support for the IP
Masquerading ready. If you installed everything as I recommend in the
beginning, you'll have the kernel sources already on your Linux
gateway. But if not, you can download the source code for <a
href="http://www.sunsite.unc.edu/pub/Linux/kernel/v2.0/linux-2.0.33.tar.gz">kernel
2.0.33</a> from Sunsite. Be patient! It's a 6M file!<p>
Just untar it in your /usr/src directory, and the do the following:
<ol>
<li>cd /usr/src/linux
<li>If you are in X, type "make xconfig". Otherwise, just "make
config".
<li>You will need to set several options in the "Networking Options"
section of the configuration. You should say "Y" to:
<ul>
<li>Network firewalls
<li>TCP/IP networking
<li>IP: forwarding/gatewaying
<li>IP: firewalling
<li>IP: masquerading
<li>IP: ICMP masquerading
</ul>
<li>Note that you need not configure any of the logging/accounting
features. Most users won't need that. Only configure it if you know
why you are doing it. I won't mention anything substantial about
accounting or logging features in this article.
<li>When you've configured all your hardware the way it should be, you
will want to click on "Save & Exit" if you're running "make xconfig".
If you need help determining how your kernel should be set up, you
need to consult the resources at <a
href="http://www.linuxresources.com/">Linux Resources</a> to find out
how to best compile your kernel to support all your hardware
correctly.
<li>If you are <i>reasonably</i> certain your kernel configuration is
correct, you will type in "make dep ; make clean ; make zlilo". If
you
are compiling in loadable module support for certain items, you will
want to also do "make modules ; make modules_install" after "make
zlilo" finishes. If "make zlilo" finishes with saying something about
the kernel being too big (usually a result of trying to compile too
many drivers into the kernel directly, rather than as modules), then
you will want to try "make bzlilo", which allows for larger kernel.
<li>When you complete the previous step, you will want to reboot the
machine so that the new kernel can take over. Provided you configured
your kernel correctly, you'll be booting up a system capable of IP
forwarding and masquerading!
</ol>
<A name="fire"></A>
<h3>Configuring IP Forwarding Firewall</h3>
<P>
The next step along the path to having a Linux machine that can act as
a gateway to the Internet is to configure IP forwarding. IP
forwarding can be a very complicated and involved thing, however, to
act as a simple gateway and firewall to the Internet, all we need to
do is configure the forwarding rules so that packets of all types
found on the ethernet interface are copied onto ppp interface.<p>
Please be aware that you should be fully informed of the security
concerns of this. I recommend that you read some materials on
security, keep a copy of <a
href="http://www.sunsite.unc.edu/pub/Linux/system/network/admin/satan-1.1.1.linux.fixed2.tgz">SATAN</a>
handy, and consult some security experts if you worry about security.
If you have a dial-up service to a local ISP, there is a lower
probability that you will be hacked on than if you are using a
university as your ISP. College kids aren't necessarily malicious,
but they can be deemed a security risk, as they are usually more
"inquisitive" than the typical Windoze 95 user at home who happens to
be a customer of your local ISP. Don't take me as Gospel Truth, check
into it for yourself and find out the issues about security if it is
something you want to know about.<p>
The first thing to have is the ipfwadm package installed on your
system. If you have it already installed and your kernel has been
compiled in the previous step to support packet forwarding, then
you're set, and you can move onto the actual configuration of the
firewall. If you are using Red Hat 4.2, the package can be found at
/[mountpoint]/RedHat/RPMS/ipfwadm-2.3.0-2.i386.rpm. If you are using
Red Hat 5.0, you should find it on the first CD of the set, in
/[mountpoint]/RedHat/RPMS/ipfwadm-2.3.0-5.i386.rpm. If you're using
Red Hat, you will note that you'll also have to modify the file
/etc/sysconfig/network, making the line containing "FORWARD_IPV4" to
say "FOWARD_IPV4=true". For Slackware, you should find installed in
the base TCP/IP package (N6, "tcpip.tgz"), so if you have TCP/IP
networking installed, it should already be there. If you need to
download it, the source can be found at its <a
href="http://www.xos.nl/linux/ipfwadm/">home page</a>.<p>
Once you have the package installed, you need to know how to use it!
Depending on how secure you would like it to be, you can make a few
changes to what I have here. What you want to do is flush the table
of all previous firewall forwarding entries, set a default policy for
either accepting or rejecting packets, and then tell it how to forward
packets between different interfaces. For example, the following
script will flush all forwarding rules, set the default policy to
"accept" packets, and will forward packets between all of the
available interfaces:
<pre>
#!/bin/sh
ipfwadm -F -f
ipfwadm -F -p accept
ipfwadm -F -a m -S 192.168.1.0/24 -D 0.0.0.0/0
</pre>
We can view the IP forwarding rules by issuing the command "ipfwadm -F
-l -n", which will list the rules numerically. If we do that, we will
get output looking like this:
<pre>
IP firewall forward rules, default policy: accept
type prot source destination ports
acc/m all 192.168.1.0/24 0.0.0.0/0 n/a
</pre>
This tells us that any packets going from our network to anything
other than just our network will be forwarded between all of the
interfaces. Now, if we specify an additional "-e" option to the
previous command, we get extended output of the forwarding rules.
This is to our advantage, but you should have a 132 character wide
screen when you run it. Here is a sample output:
<pre>
IP firewall forward rules, default policy: accept
pkts bytes type prot opt tosa tosx ifname ifaddress source
destination ports
113 9452 acc/m all ---- 0xFF 0x00 any any
192.168.1.0/24 anywhere n/a
</pre>
Thus, we can see that even though IP forwarding can be incredibly
complicated and selective, we can write a simple script which will do
all the work for us and establish a forwarding firewall.<p>
If you read the manpage for ipfwadm, you will find that the -W option
may be used to specified. For simple situations and a simple network
in a generally trusted environment, the -W option isn't necessary,
because you are probably interested in having <i>all</i> interfaces
able to see <i>all</i> packets. However, if you are interested in
keeping certain interfaces from receiving packets, you may use the -W
option for security.<p>
<A name="pppd2"></A>
<h3>Configuring pppd</h3>
<P>
The first thing we want to do is configure pppd, because it's often
easier to test out than diald. To do this, we want to create a chat
script, which will dialog with the ISP, and establish the connection.
You will want to read the man page for "chat" first, but here is an
example of a chat script I use:
<pre>
REPORT CONNECT ABORT BUSY '' atdt5551212 CONNECT '' : tkunz : PaSsWoRd
action ppp
</pre>
>From the manpage:<br>
<pre>
This sequence will expect nothing; and then send the
string ATDT5551212 to dial the telephone. The expected
string is CONNECT. If the string CONNECT is received the
remainder of the script is executed. In addition the pro-
gram will write to the expect-file the string "CONNECT"
plus any characters which follow it such as the connection
rate.
</pre>
First, the script will report what the modem returns after "CONNECT"
into the report file, to be analyzed later, in order to diagnose what
could have gone wrong with the dial-up. The ABORT string means to
abort the script should it see the "BUSY" string returned by the
modem. After that, this script will diald "555-1212" as the phone
number, and wait for the CONNECT message to come back from the remote
end. It will then wait for a colon (":"), and reply with "tkunz". It
will wait for another color (":"), and reply with "PaSsWoRd". When
the string "action" is received from the remote end, it replies with
"ppp" and the chat script terminates. Chat will then pass control
back to the program that called it. But here's another script that
will work fine, provided we don't need the "REPORT" error checking,
and we don't ever expect to get a busy signal:
<pre>
atz OK atdt5551212 CONNECT name: tkunz word: PaSsWoRd action: ppp
</pre>
This one will do the same thing, only it will initialize the modem to
the default setting by issuing "atz" first, and instead of expecting
only a colon, it waits for "name:" and "word:" to be received before
issuing "tkunz" and "PaSsWoRd", respectively, to the remote end.<p>
These simple one-line scripts like the above examples can be used with
chat to automate the login procedure with your ISP.<p>
pppd uses chat to establish a connection, and then when chat
terminates, pppd continues to dialog with the remote end, determining
its local and remote IP addresses, and then pppd follows the other
command line options to secure a reliable connection.<p>
To give you an idea of what a set of scripts would look like that
starts a PPP connection, here is a sample of something I use to
manually bring up a PPP connection to my ISP.<p>
The contents of a file in my own directory, named "startppp":
<pre>
#!/bin/sh
/usr/sbin/pppd /dev/cua3 115200 connect 'chat -f /etc/ppp/chatscript'
defaultroute crtscts proxyarp passive
</pre>
This tells pppd to use my modem, located on /dev/cua3 (COM4 in DOS),
at a speed of 115200, which my 33.6kbps modem can handle. The
"connect" parameter says to use the next quoted string as the
command-line which will connect pppd to the remote host.
<ul>
<li>
Note to programmers: pppd connects its stdin and stdout to the stdin
and stdout of the command-line specified by the "connect" option.
This is good to know, if chat doesn't work with your modem. This is
often the case with PCMCIA modems or some non-standard modems, so you
might decide to write a shell script incorporating "expect" and/or
other text utilities, or a Perl script that does the same. A chat
replacement is only required to use stdin and stdout to dialog with
the remote end and then exit by returning 0. See the "chat" manpage
for more details on termination codes.
</ul>
<P>
The option "defaultroute" tells pppd to modify the routing tables so
that this connection is added as a default route to the rest of the
world. The "crtscts" option tells pppd to use hardware flow control
for the modem, a MUST for modems faster than about 9600 baud.
"proxyarp" says to add an ARP entry for the local and remote systems
to the ARP table. The "passive" option tells pppd to be patient about
receiving LCP packets from the ISP. If pppd does not immediately
receive an LCP packet from the remote end, it drops carrier. I have
personally found this to be the "magic ingredient" to getting pppd
working with several different ISP's.
The contents of the file /etc/ppp/chatscript, used by "chat" in
"startppp":
<pre>
REPORT CONNECT ABORT BUSY '' atdt5551212 CONNECT '' : tkunz : PaSsWoRd
action ppp
</pre>
Substitute in your login name, password, and the command which starts
ppp (if any) for the appropriate fields in the
/etc/ppp/chatscript, and see what happens. You may need to
contact your ISP if you have never used pppd in Linux before to
establish a PPP connection, to determine if there are specific options
necessary to make and sustain a PPP connection. You can try the above
script and then watch the /var/log/messages file to see what happens.
You might need to modify your /etc/syslog.conf file to get the
messages printed to the right location if you use Red Hat. I prefer a
slightly modified Slackware /etc/syslog.conf, which is shown here:
<pre>
# /etc/syslog.conf
# Very Important! All whitespace are TABs, not " " (space) characters!
#
*.=info;*.=notice /var/log/messages
*.=debug /var/log/debug
*.warn /var/log/syslog
</pre>
After making this your syslog.conf file, you can do a "touch" on
/var/log/messages, /var/log/debug, and /var/log/syslog, restart
syslogd and watch the messages appear. Occaisonally, I've noticed
strangeness with syslogd not wanting to give up the previous
configuration, so you might find a reboot rather than just a restart
of syslogd is in order.<p>
Once you have syslogd logging the right level of messages to the
locations mentioned above, you can watch the progress of pppd from one
window or virtual console while you execute "startppp" from another.
By watching /var/log/messages (and possibly by watching the modem
lights if you have an external modem), you can determine if chat
succeeded or failed, or if the right options were specified to pppd.
As root, the command "tail -f /var/log/messages" will enable you to
see messages as they are dumped into /var/log/messages.<p>
By experimentation, you should be able to get a PPP connection started
by using these scripts and commands. Again, I mention that you might
have to call your ISP to find out if any special LCP or IPCP options
need to be set.<p>
<A name="diald2"></A>
<h3>Configuring diald</h3>
<P>
By this time, you should be able to regularly initiate a PPP link to
your ISP by executing "startppp", and you should be able to use web
browsers and the like to get onto the Internet from the other machines
on the network once you have the IP forwarding rules installed. The
next peice of the puzzle is diald. diald is designed as a
demand-dialer, meaning that when it senses that you want to get from
the local network out onto the Internet, it dials your ISP and sets up
the connection for you.<p>
The first thing to realize is that we are going to have to change the
way we think about pppd and chat for the moment. Before, in our
previous script in the section about configuring pppd, we had pppd
start up, then issue the "connect" command. After that occurred, pppd
would run according to the options we put on the command line. In
diald, we have to recognize that diald will be handling many of the
details that pppd handled before. These details include the dialing
script and options that would normally be passed to pppd. diald will
be responsible for implementing these things now, not pppd.<p>
What diald does is it creates a "virtual" interface, sl0, which is a
slip interface to nowhere. We will have it assign the IP address of
192.168.0.1 to sl0, and an IP address of 192.168.0.2 to the remote end
(basically <i>nothing!</i>) of the fake slip interface. Then it
creates a route so that traffic not intended for the local network
will go into sl0. When diald finds packets being copied onto sl0, it
realizes that those packets should go into the Internat, and starts
the dialing process. In order to make our particular network
arrangement work, we have to set up the IP forwarding to be
promiscuous, in a sense, in that it forwards between all interfaces,
including sl0. Thus, packets which are generated by one of the other
machines on the network will go into the Linux gateway, the IP
forwarding mechanism will copy them onto the sl0 interface if they are
not destined for only the local network, and then diald will take
over, starting the dialing process and pppd to bring up the link.<p>
The manpage of diald-examples should have been installed on your
system when you installed it. If you read that, you will probably
find your own situation there in the manpage, however, most of you
will probably find that it corresponds with the section named "A Leaf
Node with Dynamic Local Address using PPP". The following comes
directly from the diald-examples(5) manpage for this situation: <p>
<pre>
mode ppp
connect /etc/diald/connect
device /dev/ttyS1
speed 115200
modem
lock
crtscts
local 192.168.0.1
remote 192.168.0.2
dynamic
defaultroute
include /usr/lib/diald/standard.filter
</pre>
To start off with, you should have the above as your initial
/etc/diald.conf file. We will add options to it later.
At this point, please understand that diald has to know exactly where
to find the external programs of route, ifconfig, and pppd. This
article assumes that you have installed pppd, ifconfig, and
route into their default locations, which are:<p>
<pre>
/usr/sbin/pppd
/sbin/ifconfig
/sbin/route
</pre>
If for some reason you do not have them installed in the above
locations, please make links or move them to the appropriate
locations.<p>
Now we come to the part where we modify that initial /etc/diald.conf
file. First of all, we have created a working chat script in an
earlier part of this article, "Configuring pppd". Using that
information, we modify the lines starting with "connect ...", "device
..." and "speed ..." to reflect your configuration. If you followed
my directions exactly in "Configuring pppd" and have a 33.6kbps modem
on COM4 like I do, then you would get a diald.conf that looks like
this: <p>
<pre>
mode ppp
connect "chat -f /etc/ppp/chatscript"
device /dev/cua3
speed 115200
modem
lock
crtscts
local 192.168.0.1
remote 192.168.0.2
dynamic
defaultroute
include /usr/lib/diald/standard.filter
</pre>
Note that if you have a 28.8k, 33.6k, or 56k modem, your "speed ..."
line will look the same. If you're using a 14.4k, you'll most likely
have to use "speed 57600". Also, make sure you use the correct number
of the COM port. COM ports in DOS are one higher than the appropriate
cua number, since DOS starts numbering from "1" and unix tends to
number things starting from "0".<p>
One thing to note about the diald.conf file is the set of options
which would normally have been specified to pppd. According to the
diald manpage, you must <i>not</i> specify those as direct options to
pppd. This is one of those details handled only by diald. In our
original "startppp" script, we specified "... defaultroute crtscts
proxyarp passive". In our new situation, using diald instead of pppd
to manipulate those options, we need to set those here in diald.conf.
All but the "passive" option can be specified. Thus, we get a
diald.conf that looks like this: <p>
<pre>
mode ppp
connect "chat -f /etc/ppp/chatscript"
device /dev/cua3
speed 115200
modem
lock
crtscts
local 192.168.0.1
remote 192.168.0.2
dynamic
defaultroute
proxyarp
include /usr/lib/diald/standard.filter
</pre>
If we need to add the "passive" command to pppd to make it work with
your ISP correctly, then we can insert a new line into the above of
the form:<p>
<pre>
pppd-options passive
</pre>
The above diald.conf <i>should</i> get you started with a working
connection to your ISP. If not, you may need to consult your ISP's
technical support line to find out what they recommend.<p>
At this point, you should be able to start diald and watch the
messages in /var/log/messages appear which it generates upon start-up.
After diald starts, you should also be able to send packets from other
nodes of your network to the Internet, and then watch as diald
automatically dials out and establishes a connection. If not, go back
over the previous steps to find out what went wrong.<p>
<A name="time"></A>
<h3>Setting Time-Outs and Other Options</h3>
A very useful feature of diald is its ability to detect inactivity,
and then bring down the ppp link appropriately after a user-specified
amount of time. If you have a single phone line in your home, which
you need to use only in short spurts for dialing out, you'll enjoy
this feature. Or if you're a corporate entity who is charged on
5/10/15 minute increments, you can be sure that the link will go down
after a certain time of inactivity, keeping costs low.<p>
There are also important variables which are not associated with the
link uptime itself, but with the time that different portions of diald
take to execute or time-out. For example, if dialing your ISP and
passing the username, password and related actions take more than 60
seconds, typically, you will want to add a line to the file that says
something like:<p>
<pre>
connect-timeout 120
</pre>
Or, if you wish to have diald attempt a redial 10 times before giving
up and only wait 15 seconds to clear the modem between dials, you will
want to add in the following two lines:<p>
<pre>
retry-count 10
redial-timeout 15
</pre>
You may also wish to play with some of the other options that diald
has to offer. For example, one option that can be useful is
"two-way". This tells diald that if carrier is dropped while in
operation, that it will not retry dialing. What good is that? Well,
if you have to forcibly terminate the PPP connection to your ISP
(killing off pppd manually to free the line, physically pulling the
phone line connection, etc.) diald will not try to outsmart you and
dial again. If you have a somewhat dedicated line, and you are not
concerned about how long you are connected to your ISP, you won't need
that option very much, as you'll probably stay connected for longer
periods of time.<p>
If you are concerned with accounting for the time that is spent
online, then you will want to play with the "accounting-log ..."
option. The parameter to "accounting-log" should be the full pathname
of a file which will log the times when the link comes up and goes
down, and how much data was sent down the wire. But I said I wouldn't
spend any time talking about accounting and logging ...<p>
The diald manpage is rich with options, and I would recommend that you
read it in parallel with reading this article. Diald is wonderfully
configurable, and can meet a <b>wide</b> variety of needs, depending
on how complex of an arrangement you wish.<p>
<A name="app"></A>
<h3>Application Notes</h3>
<P>
OK! Now you can go to any node of your network, start up {Netscape,
IE, Arena, Mosaic, any browser} and get to somewhere out on the rest
of the Internet. However, why does it seem like sometimes your Linux
gateway almost randomly fires up a connection? What's it doing?<p>
Well, now you need to delve into the particular applications on your
network and how they're configured. Two of the big things to check
are mail client and web browsers which contain mail clients. If your
mail client makes requests for new mail, it will generate a packet
which goes to your gateway, and initiates a call. This means that
while the Internet connection is down, someone with a mail client up
and running somewhere on your local network can unwittingly cause the
gateway to establish a connection. This can be annoying and/or
costly, both for the typical home user and the corporation. I know
that I've accidentally done this to my wife on a number of occaisons,
where my gateway attempted to dial out while she was on the phone with
someone! (But she's a wonderful, patient, forgiving wife.)<p>
To fix this, what you need to do is to inform your staff (or family)
that once they finish with their mail client, they should terminate it
immediately. And they should also be informed that they should turn
off the automatic mail-fetching for any mail client that they use,
especially if you are billed for connection time to your ISP or per
minute of call (European countries often bill for even local
calls).<p>
Another thing to watch out for is the /etc/resolv.conf on the unix
hosts on your network. You must not have any nameservers which are
outside of your local network listed in it, or else every application
that accepts a hostname will generate packets and cause your gateway
to dial out. For this reason, it's wise to keep every hostname your
local network needs in /etc/hosts on each unix machine. If your local
network is large enough to warrant the effort, you might also set up
your own local nameserver to handle the name requests. A local
nameserver with its own maps for the local domain, and a caching
nameserver for outside requests is probably the most efficient way of
handling that. If you are going to be using a local mail agent like
sendmail, then you will want to be sure to configure it in such a way
that it will not cause the gateway to dial-up the ISP at every
instance of outgoing mail. You'll want it spooled until a connection
is available, or at a routinely scheduled time when all queued mail
will be transmitted out.<p>
Obviously, this document is not going to go into any detail about how
to configure the various applications on your network around using a
demand-dialed gateway. It is useful, however, to be aware of some of
the issues you will face when you add different applications and
platforms to your network, and why things may not be going the way you
initially supposed they would. If you are faced with a larger network
which requires greater upkeep in order to keep it working right, and
high bandwidth to the Internet on a regular basis, it may be time to
consider investing in faster connections (ISDN, T1, T3, OC3, etc.) and
leased lines which better suit your needs. Note that diald can work
with ISDN, but in a larger-scale network with higher bandwidth
demands, a full-time connection may be the best solution.<p>
<A name="final"></A>
<h3>Conclusion</h3>
<P>
Well, it's seems apropriate to say that configuring a small network
with demand dialing via diald is a task which can be <i>quite</i>
involved, depending on the complexity of your network. But if you
have fairly "ordinary" needs, you can follow the above procedures to
get a working and reliable demand-dialed connection. Many, at this
point, will say "Well, what are 'ordinary needs' anyway?" or "How big
of a network will this support?". The answer is subjective, however I
can say with reasonable certainty that a network of 2 to 8 machines,
each running their own web browsers, mail clients, and the like, will
be quite adequate over even a 28.8kbps modem. The connection I get to
my local ISP rarely gets past 28.8kbps on my 33.6kbps modem, because
of the lines in my area, and often drops down to 21.6kbps or so, yet I
still get reasonably quick response from having 2 or 3 machines
accessing the Internet simultaneously. If you lust for speed, then
you will do well to get a 56kbps modem, and a line to your ISP that
can sustain 56kbps (yes, 53k download by FCC law). From my
experience, diald will have no trouble with a 56kbps, provided it is
either external and connected to a 16550 UART, or if you have built
some version of a PnP configuration manager which can reliably
configure an internal 56k modem.<p>
<!--===================================================================-->
<P> <hr> <P>
<center><H5>Copyright &copy; 1998, Tom Kunz <BR>
Published in Issue 26 of <i>Linux Gazette</i>, March 1998</H5></center>
<!--===================================================================-->
<P> <hr> <P>
<A HREF="./index.html"><IMG ALIGN=BOTTOM SRC="../gx/indexnew.gif"
ALT="[ TABLE OF CONTENTS ]"></A>
<A HREF="../index.html"><IMG ALIGN=BOTTOM SRC="../gx/homenew.gif"
ALT="[ FRONT PAGE ]"></A>
<A HREF="./ayers.html"><IMG SRC="../gx/back2.gif"
ALT=" Back "></A>
<A HREF="./obrien.html"><IMG SRC="../gx/fwd.gif" ALT=" Next "></A>
<P> <hr> <P>
<H4>
"Linux Gazette...<I>making Linux just a little more fun!</I>"
</H4>
<P> <HR> <P>
<!--===================================================================-->
<center>
<H2>The Yorick Programming Language</H2>
<H4>By <a href="mailto:cobrien@optimsys.com">Cary O'Brien</a></H4>
</center>
<P> <HR> <P>
<H3>Contents:</H3>
<ul>
<li><a HREF="./obrien.html#intro">1. Introduction</A>
<li><a HREF="./obrien.html#basic">2. Basic operations</A>
<li><a HREF="./obrien.html#prog">3. Programming</A>
<li><a HREF="./obrien.html#array">4. Advanced Array Operations</A>
<li><a HREF="./obrien.html#graphics">5. Graphics Operations</A>
<li><a HREF="./obrien.html#final">6. Closing Remarks</A>
<li><a HREF="./obrien.html#resource">7. Additional Resources</A>
</ul>
<P> <HR> <P>
<A name="intro"></A>
<H3>1. Introduction</H3>
<P>
Linux leverages a vast amount of academic software, either easy ports
of existing Unix packages or, increasingly in recent years, software
that is already ready to run under Linux.
One example is Yorick, and this article is an attempt to
provide a brief overview of the nature and capabilities
of this system.
<P>
Yorick is not just another calculator -- readable syntax, array
notation, and powerful IO and graphics capabilities make Yorick a
favorite tool for scientific numerical analysis. Machine-independent
IO, using the standard NetCDF file formats, simplifies moving
applications between hardware architectures.
<P>
Yorick is an interpreted language for numerical analysis, developed
at Livermore Labs by David H. Munro. Implemented in C, it is freely
distributed under a liberal copyright. Yorick runs on a vast
range of machines, from 486SX Linux Laptops (in my case) to Cray YMP
supercomputers.
<P>
Who uses Yorick? The majority of users are physicists,
many with access to the most powerful computers in the world.
Specific applications include Astrophysics, Astronomy, Neurosciences,
Medical Image Processing and Fusion Research.
<P>
In this article I will discuss the basics of running Yorick, describe
the key array operations, and briefly discuss array operations, programming,
and graphics. I hope that this quick look is enough to get the more
mathematically inclined of you to give Yorick a try.
<P> <HR> <P>
<A name="basic"></A>
<H3>2. Basic operations.</H3>
<P>
When invoked without arguments, Yorick presents a typical
command line interface. Expressions are evaluated
immediately, and the result is displayed. Primitive
types include integers, floating point values, and strings, and
all the built-in functions and constants you would expect are
present.
<P>
Variable names are unadorned -- no leading $, and need not
be pre-declared, and C style comments are supported.
<P>
<H4>Arrays</H4>
<P>
One might not expect an interpreted language to be suitable for
numerical analysis -- and indeed this would be the case if arrays
were not built into the language. Arrays are first-class objects
that can be operated on with a single operation. Since the
virtual machine understands arrays, it can apply optimized
compiled subroutines to array operations eliminating the speed
penalty of the interpreter.
<P>
Arrays can be created explicitly:
<pre>
> a1 = [1.1, 1.2, 1.3, 1.4, 1,5]
</pre>
And elements can be accessed singly or as a subset, with 1 being
the origin. Parenthesis indicate the indexing operation, and
a single index or a range of indexes can be specified.
<pre>
> a1
[1.1,1.2,1.3,1.4,1,5]
> a1(2)
1.2
> a1(1:3)
[1.1,1.2,1.3]
</pre>
Since array operations are built into the language, functions
applied to the array are automatically applied to all elements
at once.
<pre>
> sqrt(a1)
[1.04881,1.09545,1.14018,1.18322,1,2.23607]
</pre>
Arrays are not limited in dimension. The rank (number of indices) of
an array is not limited to one (a vector) or two (a matrix), but can
be as large as desired. Arrays of rank 3 can be used to represent
the distribution of a parameter across a volume, and an array of
rank 4 could model this over time.
<P>
<H4>On-line Help</H4>
<P>
Yorick also provides a simple but effective help system. Executing
the help command describes the help system. Executing it with
a command name as an argument provides information on that command.
<P> <HR> <P>
<A name="prog"></A>
<H3>3. Programming</H3>
<P>
Yorick provides a complete programming language that closely matches C
in terms of control flow, expressions, and variable usage. For
example,
<pre>
> for(i=1; i&lt;10; i++) { print,1&lt;&lt;i; }
</pre>
print the powers of two just as you would expect, and function
declarations, introduced with func, work as expected.
<pre>
> func csc(x) {
> return 1/sin(x);
> }
</pre>
There are differences -- variables need not be declared, and arrays
are much more powerful than C. The major difference is in function
invocation. Passing arguments to a function in parenthesis causes an
evaluation and printing of the result, however passing arguments
separated by commas simply executes the function and does not return
the result. Since in most cases intermediate results are not
required, many scripts contain function calls of the form f,x,y rather
than the more familiar f(x,y).
<P>
Having a programming language close to C allows easy migration between
Yorick for prototyping and C for final implementation. However, as
several Yorick users have indicated, moving to C was often unnecessary
-- the Yorick program proved to be fast enough to get the job done,
and with a minimum of programming effort.
<P>
If C extensions are required, a straightforward framework allows
extending the Yorick command language with whatever new operations
are necessary.
<P> <HR> <P>
<A name="array"></A>
<H3>4. Advanced Array Operations</H3>
<P>
Now things get really interesting. Yorick has a compact
and sophisticated mechanism for describing array indexing
and operations, which are used to precisely specify the
desired operation to the interpreter.
<P>
As you recall, applying an operation to an array
causes the operation to be applied to each element
of the array. For example
<pre>
a = [1,2,3,4,5]
sqrt(a)
[1,1.41421,1.73205,2,2.23607]
</PRE>
<P>
But what about multiplying two vectors? The default
is to perform an element by element by multiplication.
<pre>
b = [2,4,6,8,10]
a*b
[2,8,18,32,50]
</PRE>
<P>
But those of you that remember physics or linear algebra
will recall the inner and outer products. The inner
product is defined as the sum of the pairwise products:
<pre>
a(+)*b(+)
110
</PRE>
And the outer product creates a matrix out of each possible
multiplication
<pre>
a(-,)*b(,-)
[[2,4,6,8,10],
[4,8,12,16,20],
[6,12,18,24,30],
[8,16,24,32,40],
[10,20,30,40,50]]
</PRE>
<P>
The + and - symbols used where an index would be are
called special-subscripts, and provide precise control
over how array operations are executed.
<P>
The + is the matrix multiplication pseudo-index, which indicates
to Yorick along which dimension the addition part of a
matrix multiply should be performed.
<P>
The - is a pseudo-index, creating an index where one
did not exist before.
<P>
<H4>Rank-Reducing Operators:</H4>
<P>
The operators sum, min, max, and avg can be used
in place of indexes.
<pre>
a(max)
5
b(avg)
6
</PRE>
<P>
One might wonder why this is necessary, when the equivalent
functional operators (i.e. min() or avg()) exist? The reason
is that for matrices of rank more than one, the rank-reducing
index operators allow you to specify exactly how to perform
the operation. For example, given a 3x3 array, to you want
to average across rows, columns, or the entire array?
<pre>
c = [[1,2,3],[4,5,6],[7,8,9]]
dimsof(c)
[2,3,3]
avg(c)
5
c(avg,avg)
5
c(avg,)
[2,5,8]
c(,avg)
[4,5,6]
</PRE>
<P>
Here we have also introduced the dimsof() operator, which
reports the dimensions of the argument. In this case the
result tells us that c is an array of rank 2, with 3 elements
in each direction.
<P> <HR> <P>
<A name="graphics"></A>
<H3>5. Graphics Operations</H3>
<P>
Under Linux, Yorick is linked with the GIST graphics
subsystem, allowing immediate display of plots and
diagrams. Plots are interactive, allowing the user
to zoom in and out, stretch axes, and crop the
displays using the mouse. Yorick is capable of
displaying sequences of plots over time as a move,
and because of this the command to prepare for
a new image is fma, or frame advance. Onward.
<P>
To plot the value of a function at evenly spaced
points we need to first create the x values.
<pre>
x = span(0,10,256)
dimsof(x)
[1,256]
</PRE>
<P>
X is now a 256 element long array with values that range
from 0 to 10.
<P>
The plg function, given vectors for the x and y
values, plots x-y graphs.
<pre>
plg, sin(x^2), x
</PRE>
<img src="./gx/obrien/2184p1.gif">
<P>
<center><H4>Plot 1</H4> </center>
<P>
The result is shown in Plot 1. Note that the arguments
are supplied y,x (not x,y). This allows Yorick to supply
a default x vector (ranging from 1 to the number of y points)
if desired.
<P>
Parametric plots are also supported. Consider the
following code which produces the spiral in Plot 2:
<P>
<pre>
window, style="vgbox.gs"
a = span(0,20,256)
x = a * sin(a)
y = a * cos(a)
plg, y, x
</PRE>
<img src="./gx/obrien/2184p2.gif">
<P>
<center><H4>Plot 2</H4> </center>
<P>
Surface plots are also available, either as a wire
frame as in Plot 3.
<pre>
#include "plwf.i"
orient3
x = span(-pi,pi,32)(,-:1:32)
y = transpose(x)
fma
plwf, sin(x)*cos(y)
</PRE>
<img src="./gx/obrien/2184p3.gif">
<P>
<center><H4>Plot 3</H4> </center>
<P>
Or a shaded surface rendition as in Plot 4:
<PRE>
fma
plwf, sin(x)*cos(y), shade=1, edges=0
</PRE>
<img src="./gx/obrien/2184p4.gif">
<P>
<center><H4>Plot 4</H4> </center>
<P>
A host of advanced graphics options are used in the
demonstration programs distributed with Yorick, and
the latest copy of the documentation has an extensive
description of graphics options. In addition, libraries
to read, write, and display PNM format images is provided.
<P> <HR> <P>
<A name="final"></A>
<H3>6. Closing Remarks</H3>
<P>
Yorick is an exceptionally rich environment for numerical
analysis. Many capabilities such as file IO, debugging,
animation, and distributed operation using MPY have been
omitted. If you are at all interested please take the
time to read through the documentation and the example
programs. You will not be disappointed.
<P> <HR> <P>
<A name="resource"></A>
<H3>7. Additional Resources</H3>
<P>
Yorick Home Page:<BR>
<A HREF="ftp://ftp-icf.llnl.gov/pub/Yorick/yorick-ad.html">
ftp://ftp-icf.llnl.gov/pub/Yorick/yorick-ad.html</A>
<P>
Yorick Archive Sites:<BR>
<A
HREF="ftp://sunsite.unc.edu/pub/Linux/apps/math/matrix/yorick-1.4.src.tar.gz">
ftp://sunsite.unc.edu/pub/Linux/apps/math/matrix/yorick-1.4.src.tar.gz</A>
<P>
Linux Software for Scientists (and Curious Layfolk):<BR>
<A HREF="http://www-ocean.tamu.edu/~baum/linuxlist.html">
http://www-ocean.tamu.edu/~baum/linuxlist.html</A>
<P>
Scientific Applications under Linux:<BR>
<A HREF="http://SAL.KachineTech.COM/">
http://SAL.KachineTech.COM/</A>
<!--===================================================================-->
<P> <hr> <P>
<center><H5>Copyright &copy; 1998, Cary O'Brien <BR>
Published in Issue 26 of <i>Linux Gazette</i>, March 1998</H5></center>
<!--===================================================================-->
<P> <hr> <P>
<A HREF="./index.html"><IMG ALIGN=BOTTOM SRC="../gx/indexnew.gif"
ALT="[ TABLE OF CONTENTS ]"></A>
<A HREF="../index.html"><IMG ALIGN=BOTTOM SRC="../gx/homenew.gif"
ALT="[ FRONT PAGE ]"></A>
<A HREF="./kunz.html"><IMG SRC="../gx/back2.gif"
ALT=" Back "></A>
<A HREF="./lg_backpage26.html"><IMG SRC="../gx/fwd.gif" ALT=" Next "></A>
<P> <hr> <P>
<H5>Copyright &copy; 1998 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_backpage26.html#authors">About This Month's Authors</a>
<li><a HREF="./lg_backpage26.html#notlinux">Not Linux</a>
</ul>
<a name="authors"></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">Jim 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 was
married at the World Science Fiction Convention in Anaheim.
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Dr. Richard L. Dubs</H4>
When Dr. Dubs is not playing with Linux, he is a Senior Scientist with a
Virginia-based defense contractor. He lives in an idyllic community in
Rockville, MD with his wife, two kids and the family cat.
<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">Tom Kunz </H4>
Tom is 24 years old, married to the most wonderful woman in the
world, and he works as a Systems Programmer for Rutgers University
Telecommunications Division. Hobbies, other than Linux, include
listening to and performing classical/romantic-period piano music,
writing piano arrangements for church, woodworking, and recreational
shooting. I can be reached at tkunz@hardees.rutgers.edu or
tkunz@fast.net.
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Mike List </H4>
Mike List is a father of four teenagers, musician,
and recently reformed technophobe, who has been into computers
since April,1996, and Linux since July.
<p>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Eric Marsden</H4>
<a href="http://www.chez.com/emarsden/">Eric</a> is studying computer
science in Toulouse, France, and is a member of the local Linux Users
Group. He enjoys programming, cycling and Led Zeppelin. He admits to
once having owned a Macintosh, but denies any connection with the the
<a href="http://locke.ccil.org/~esr/ecsl/">Eric Conspiracy Secret
Labs</a>.
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Cary O'Brien</H4>
Cary O'Brien lives in Washington DC, and refers to himself, when
pressed, as a "systems engineer". He is currently Vice President of Optim
Systems, Inc., which provides products and services to the the
telecommunications industry. He has been messing with computer
hardware and software since high school. He is married with two
children, 4 and 7, who are starting with computers even earlier.
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Alessandro Usseglio Viretta</H4>
Alessandro, European citizen and physicist, is a Ph.D. student at the Swiss Federal
Institute of Technology in Zurich. During daytime he's trying to learn the art
of cryo-electron-microscopy but at night he turns himself into the abominable
kernel-compiler.
<a name="notlinux"></a>
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<center><H3> Not Linux </H3></center>
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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>
Lots of excitement in the air these days what with free Netscape and
the debate over OpenSource. We're going through some interesting times.
<P>
Well, not much to report this montho on a personal front--work!
work! work! makes Margie a dull woman.
<P>
Have fun!
<P> <hr> <P>
<A HREF="http://www.ssc.com/ssc/Employees/Margie/margie.html">
Marjorie L. Richardson</A> <br>
Editor, <A HREF="http://www.linuxgazette.com/"><i>Linux Gazette</i></A>, <A
HREF="mailto:gazette@ssc.com">gazette@ssc.com</a>
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<I>Linux Gazette</I> Issue 26, March 1998,
<A HREF="http://www.linuxgazette.com/">http://www.linuxgazette.com</A><BR>
This page written and maintained by the Editor of <I>Linux Gazette</I>,
<A HREF="mailto: gazette@ssc.com"> gazette@ssc.com</A>
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