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<H2>August 2001, Issue 69 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
Published by <I>Linux Journal</I></H2> 

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<H1><font color="#BB0000">Table of Contents:</font></H1>




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	<LI>  <a HREF="lg_mail69.html">The MailBag</A> 
	<LI>  <a HREF="lg_bytes69.html">News Bytes</A> 
	<LI>  <a HREF="lg_answer69.html">The Answer Gang</A> 
	<LI>  <a HREF="lg_tips69.html">More 2-Cent Tips</A> 
	<LI>  <a HREF="collinge.html">HelpDex</A> , <EM>by Shane Collinge</EM>
	<LI>  <a HREF="henderson.html">Make Your Virtual Console Log In Automatically</A> , <EM>by Bryan Henderson</EM>
	<LI>  <a HREF="mathew.html">Creating a Kernel Driver for the PC Speaker</A> , <EM>by Cherry George Mathew</EM>
	<LI>  <a HREF="nielsen.html">Combining Perl and PostgreSQL, Part 2: Procedures with PL/pgSQL</A> , <EM>by Mark Nielsen</EM>
	<LI>  <a HREF="okopnik.html">Learning Perl, part 5</A> , <EM>by Ben Okopnik</EM>
	<LI>  <a HREF="orr.html">DMCA in the news: Russian programmer arrested, nerds protest for his release</A> , <EM>by Mike Orr</EM>
	<LI>  <a HREF="peda.html">Installing Tomcat on Linux</A> , <EM>by Allan Peda</EM>
	<LI>  <a HREF="qubism.html">Qubism</A> , <EM>by Jon "Sir Flakey" Harsem</EM>
	<LI>  <a HREF="spiel.html">Numerical Workbenches</A> , <EM>by Christoph Spiel</EM>
	<LI>  <a HREF="lg_backpage69.html">The Back Page</A> 
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<H3 ALIGN="center"><EM>Linux Gazette</EM> Staff and The Answer Gang</H3>
<BLOCKQUOTE>
<STRONG>Editor:</STRONG> Michael Orr<BR>
<STRONG>Technical Editor:</STRONG> Heather Stern<BR>
<STRONG>Senior Contributing Editor:</STRONG> Jim Dennis<BR>
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<H1><A NAME="wanted"><IMG ALIGN=MIDDLE ALT="" SRC="../gx/mailbox.gif">
The Mailbag</A></H1> <BR>
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<center><H3><font color="maroon">HELP WANTED : Article Ideas</font></H3></center>
<P>
<P> Send tech-support questions, answers and article ideas to The Answer Gang
&lt;<A HREF="mailto:linux-questions-only@ssc.com"
	>linux-questions-only@ssc.com</A>&gt;.  Other mail (including
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<A HREF=../faq/index.html><I>Linux Gazette</I> FAQ</A> to see if it has been
answered there.</STRONG>

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<UL>
<!-- index_text begins -->
<li><A HREF="#wanted/1"
	><strong>Compact Flash Card</strong></a>
<li><A HREF="#wanted/2"
	><strong>Booting x86 from flash using initrd as root device</strong></a>
<!-- index_text ends -->
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<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">Compact Flash Card</FONT></H3>
Wed, 20 Jun 2001 12:20:27 +0800
<BR>Kamal (<a href="mailto:linux-questions-only@ssc.com?cc=kamal@eutech.slt.lk">kamal from eutech.slt.lk</a>)

<P>
I have a problem in adding a new file system in to a device called
mediaEngine. It is a product of brightstareng.com
There is slot for a Compact Flash. I bought a compact flash and added
it, but thenit does not recognise the card. it says there isan i/o
error. the mke2fs does not work properly. I am not able to mount even.
</P>
<P>
pleaese help me regarding this.
</P>
<P>
thanking you inadvance
</P>
<P>
kamalakanth
</P>

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<P> <A NAME="wanted/2"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">Booting x86 from flash using initrd as root device</FONT></H3>
Mon, 09 Jul 2001 18:50:25 +0530
<BR>S. Manohar (<a href="mailto:linux-questions-only@ssc.com?cc=manohar@hclt.com">manohar from hclt.com</a>)

<P>
Hello Everybody,
</P>
<P>
I am trying to develop a x86 target which boots from Flash. I have
taken the BLOB bootloader  (taken from LART
project based on ARM processor.)  and  am modifying it for X86. So far I
am able to get the Linux kernel booted. But when it
comes to the mounting of rootfile system I am stuck. ( The blob
downloads the kernel image and initrd image  into RAM from
Flash/through serial line).
</P>
<P>
1. I am getting the compressed  kernel image  in RAM at 0x100000 through
serial line.
</P>
<P>
2. I am getting the compressed ramdisk  image(initrd)  in RAM at
0x400000 through serial line.
</P>
<P>
3. The kernel gets uncompressed and boots correctly till the point of
displaying the message
</P>
<P>
RAMDISK: Compressed image found at block 0.
and then hangs.
</P>
<P>
4. After debugging I have found that control comes till gunzip function
inlinux/lib/inflate.c  but never comes out of the function.
</P>
<P>
5. The parameters I have set at the begining of setup_arch function in
linux/arch/i386/kernel/setup.c are as follows
</P>

<blockquote><pre>         ORIG_ROOT_DEV = 0x0100
         RAMDISK_FLAGS = 0x4000
         INITRD_START = 0x400000
         INITRD_SIZE =  0xd4800    (size of compressed  ram disk image)
         LOADER_TYPE = 1
</pre></blockquote>
<P>
Has anyone faced such problem before?  If so what needs to be done?
</P>
<P>
Are the values for the  parameters mentioned above correct? Are they the
only information to be mentioned to the kernel for
locating and uncompressing the RAMDISK image and make it boot?
</P>
<P>
Is there any bootloader readily available for x86 platform for booting
from Flash also with serial downloading facility?
</P>
<P>
Please help
</P>
<P>
With Kind Regards,
<br>manohar
</P>

<!-- end 2 -->
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<!-- *** BEGIN copyright *** -->
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	>Copyright &copy;</a> 2001
<BR>Published in issue 69 of <I>Linux Gazette</I> August 2001</H5>
<H6 ALIGN="center">HTML script maintained by
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<!-- =================================================================== -->
<center><H3><font color="maroon">GENERAL MAIL</font></H3></center>
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<!-- BEGIN GENERAL MAIL -->

<UL>
<!-- index_text begins -->
<li><A HREF="#mailbag/1"
	><strong>KEEP UP THE GOOD WORK !!!!</strong></a>
<li><A HREF="#mailbag/2"
	><strong>not happy</strong></a>
<li><A HREF="#mailbag/3"
	><strong>Blinking Icons</strong></a>
<li><A HREF="#mailbag/4"
	><strong>question</strong></a>
<li><A HREF="#mailbag/5"
	><strong>"Those were the days"</strong></a>
<li><A HREF="#mailbag/6"
	><strong>RE: Linux Gazette Kernel Compile Article.</strong></a>
<li><A HREF="#mailbag/7"
	><strong>Parrallel processing</strong></a>
<li><A HREF="#mailbag/8"
	><strong>response to: Yet Another Helpful Email</strong></a>
<li><A HREF="#mailbag/9"
	><strong>anser guy</strong></a>
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<P> <A NAME="mailbag/1"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">KEEP UP THE GOOD WORK !!!!</FONT></H3>
Mon, 9 Jul 2001 09:53:21 -0700
<BR>badjooda (<a href="mailto:gazette@ssc.com">badjooda from yahoo.com</a>)

<P><STRONG>
Remember when you said :
</STRONG></P>
<P><STRONG><FONT COLOR="#000066"><EM><BLOCKQuote>
WinPrinter Work-around
From harmbehrens on Sat, 01 May 1999
</BLOCKQuote></EM></FONT></STRONG></P>
<P><STRONG><FONT COLOR="#006633"><EM>
Hello, is there any work-around to get a gdi printer (Star Wintype 4000) to
work with Linux :-?
</EM></FONT></STRONG></P>
<P><STRONG><FONT COLOR="#006633"><EM>
Harm
</EM></FONT></STRONG></P>
<P><CODE>
. . .
</CODE></P>
<P><STRONG><FONT COLOR="#000066"><EM>
I presume that these are NOT what you wanted to hear. However, there is no
way that I know of to support a Winprinter without running drivers that are
native to MS Windows (and its GDI --- graphics device interface --- APIs).
</EM></FONT></STRONG></P>
<P>
What about using one of the Windows emulators like <A HREF="http://www.winehq.com/">WINE</A>
(<A HREF="http://www.winehq.org"
	>http://www.winehq.org</A>) ? -- Mike
</P>
<P>
Actually, a very few GDI- aka "winprinters" are supported - some Lexmarks.
I saw them first as debian packages but I'm pretty sure Linuxprinting.org
has more details.  The notes said that rumor has it some other GDI printers
work with those, but it's a bit of effort and luck.  Rather like winmodems...
-- Heather
</P>
<P><STRONG>
I Agree 100% about the GDI printers!  (I refer to them as Goll Damn M$
Imitators).  Unfortunately, until the recent developments on the federal
court case M$ has not been checked at all.  Some parts of what they, as
a Monopoly have done has been good for the IT commmunity, while other
things have really crapped on people WHO THINK!
</STRONG></P>
<P><STRONG>
Thank GOD !!!!!  Linux is around to be a thorn in their side ...
</STRONG></P>
<P><STRONG>
THe other incidious thing printer manufacs have done is stop building
as many Postscript printers.  They are all using the friggin Windows
drivers to do everything ...  .  So I have begun to play the stinkin game
by mounting SMALL 468-DX266 16 Megs Linux Print Servers running SAMBA.
THe newest ver of SAMBA even does PDC correctly.
</STRONG></P>
<P><STRONG>
Linux has been my savior in many times of need!  I have been able to
use thos stinking 386 boat anchors as LRP routers or firewalls, the
small 90 Pent to 166 Pent are becoming LTSP Linux Xwindow Terminals.  I
still have stinking  problems from time to time, yet I DON'T HAVE TO
REBOOT EVERY 24 [&amp;^%$!#]* days PER TECHNET(M$ answer to internal
pay support) FOR NT SERVERS!  I have Linux servers with uptimes of 200 +
days IN PRODUCTION!
</STRONG></P>
<P><STRONG>
I'll sign off , enough rambling and ranting for one email.  I just
found your stuff through linuxdoc.org, and I thought you HIT THE NAIL ON
THE HEAD!
</STRONG></P>
<P><STRONG>
KEEP UP THE GOOD WORK!
</STRONG></P>
<P>
The real question is, is it worth spending 50 bucks instead of 200 or more,
when you're going to spend a bunch of time making sure your driver is wired
up right?   I have an unfair advantage, since I live where these things are
sold readily, but I get to say no ... I can spend about 80 bucks on a color
printer which is actually listed as fully supported.
</P>
<P>
You may be able to mail order a good printer at a decent price.  On the other
hand, if exploring how these things all tie together under the hood is fun,
then you can improve the state of the art for such printers, and maybe some
fine day folks will be able to easily use "the GDI printer that came with
their MS windows" without having to fight with it like this.
</P>
<P>
-- Heather
</P>

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<P> <A NAME="mailbag/2"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">not happy</FONT></H3>
Thu, 5 Jul 2001 09:08:47 -0700
<BR>32009318 (<a href="mailto:gazette@ssc.com">32009318 from snetmp.cpg.com.au</a>)


<!-- sig -->

<P>
On Wed, Jul 04, 2001 at 09:26:35PM +1000, 32009318 wrote:
</P>
<P><STRONG>
i know how annoyed you guys at the linux gazette must feel as i have
been reading many back issues of the gazette and finding lots of cool
tips and trick but the question always comes up
</STRONG></P>
<P><STRONG>
CAN YOU SOLVE WINDOWS PROBLEMS
people just dont get it youre called the linux gazette and you help with
linux questions
</STRONG></P>
<P>
Unfortunately, we also have no idea where they find the reference to us that
gives them the impression we do anything in Windows... more's the pity, since
we can't beg the webmaster to take the link down.
</P>
<P>
They can certainly trip on us in search engines though, especially the worse
ones.  I can imagine someone frustrated with some Windows networking matter
tripping over our many notes about Samba, since the point is to link up to
some MSwin boxes... -- Heather
</P>
<P><STRONG>
(you do it very well i should add)
</STRONG></P>
<P>
Oh thank you, we like to hear that! -- Heather
</P>
<P>
The problem is, most people who ask Windows questions found the submission
address via a search engine, and have no idea the address belongs to Linux
Gazette or even know what Linux Gazette is.  Perhaps we should have used
an address like linux-questions-only, but we can't stop honoring the old
addresses since they are published in so many back issues and some are on
CD-ROMs that we can't change. -- Mike
</P>
<P><STRONG>
You should clearley state this in youre next issue or be humorous and
rename yourself The Not Windows Gazette
</STRONG></P>
<P>
<IMG SRC="../gx/dennis/smily.gif" ALT=":)" 
		height="24" width="20" align="middle"> They're not the only odd ones out - we've had IRIX, PC-MOS, and other
odd OS users crop up before too.
</P>
<P>
<FONT COLOR="purple">
[Ben] Even had someone trying to get root access to their rhubarb, recently...
</FONT>
</P>
<P>
Funny you should mention a name change though.  We <EM>have</EM> changed the name
of the Answer Gang mailing list to "<A HREF="mailto:linux-questions-only@ssc.com"
	>linux-questions-only@ssc.com</A>"  -- Heather
</P>
<P>
Many TAG threads have humorous comments and/or rants about off-topic
questions.  Heather also tries to guide people in her "Greetings from
Heather Stern" blurb about how to ask a good question and how not to ask
a bad question.  Finally, I have started making fun of off-topic questions
on the Back Page of the past few issues.  There's now a section on the
Back Page called "Not The Answer Gang", as well as "Wackiest Topic of the
Month".  -- Mike
</P>
<P><STRONG>
keep up the good work with linux
</STRONG></P>
<P>
Thanks bunches, we're glad you enjoy the read!  -- Heather
</P>

<!-- end 2 -->
<!--     .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.     -->
<P> <A NAME="mailbag/3"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">Blinking Icons</FONT></H3>
Wed, 18 Jul 2001 14:13:14 -0400
<BR>David Martinez (<a href="mailto:gazette@ssc.com">d_martinez7 from hotmail.com</a>)


<!-- sig -->

<P><STRONG>
I love reading LG every month, especially TAG, and 2cent tips.  But the new
blinking question and exclamation icons are somwhat annoying.  Any chance of
going back to the old ones? 
<IMG SRC="../gx/dennis/smily.gif" ALT=":)" 
		height="24" width="20" align="middle">
</STRONG></P>
<P><STRONG>
thanks for all the good work!
</STRONG></P>
<P>
blinking?  They're not supposed to blink.  In fact, if they are it's been
that way for <EM>YEARS</EM> ... since I first provided .gif files with the ! and ?
in them in blue, instead of with those stupid "!" and "?" that nobody could
read.
</P>
<P>
It would mean I accidentally had layers in them.  But there's no loop command,
so even if you see that briefly it should stop.  Is that what you are seeing,
or does it continue to blink?  Did you change browsers at all recently?  If
so to which one?
</P>
<P>
We have been trying to improve browser compatability lately anyway 
<IMG SRC="../gx/dennis/smily.gif" ALT=":)" 
		height="24" width="20" align="middle"> Thanks
for bringing it up.
</P>
<P>
[ turning to my fellow editor ] Mike, did anybody run any scripts against the
graphic images recently that I need to know about?
</P>
<P>
-- Heather
</P>
<P>
No, we haven't changed those images.  I've threatened to change all .gif's
to .png or .jpg and change all the links, but haven't done it yet.  I've only
used blinking text once or twice and that wasn't in the TAG column.
</P>
<P>
Also, LG is probably the only site in the world that requires NON-ANIMATED
logo images from its sponsors.  Because I personally have a strong
intolerance for unnecessary animations.
</P>
<P>
-- Mike
</P>
<P>
The "blinking Icons" are actually three layer gifs with one backround (white
bubble) and 0ms display time and two layers (question mark and shadow) with
100ms display time in combine mode (will be overlayed over the previous one).
</P>
<P>
opera5.0/Linux displays them on a strange blue background (seems to have a
gif problem, also with other gifs not only these little ones).
</P>
<P>
If you want a scriptable tool (besides gimp) there is a program called
pngquant which can do the color (and size) reduction on png files which
convert will not do.
</P>
<P>
-- K.-H.
</P>
<P><DL><DT>
Mike didn't find the utility in <A HREF="http://www.debian.org/">Debian</A> but its homepage is:
<DD><A HREF="http://www.libpng.org/pub/png/apps/pngquant.html"
	>http://www.libpng.org/pub/png/apps/pngquant.html</A>
</DL></P>
<P>
-- Heather
</P>

<!-- end 3 -->
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<P> <A NAME="mailbag/4"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">question</FONT></H3>
Tue, 3 Jul 2001 19:16:24 EDT
<BR>Mattybiz (<a href="mailto:gazette@ssc.com">Mattybiz from aol.com</a>)

<P><STRONG>
Everyone I know is having the same problem. Not only is the Telnet completely
outdated, but it simply does not work for people off campus in most
areas...
</STRONG></P>
<P>
Hint: putty, one of the ssh clients for Windows that we keep pushing, is also
a better "normal telnet" client for Windows. -- Heather
</P>
<P><STRONG><FONT COLOR="#000066"><EM>
And last weekend I discovered that the public library in Halifax, Nova Scotia,
has putty as the <EM>default</EM> terminal emulator on their public Windows
terminals!!!  Way to go, library!  And switching between telnet and ssh in
putty is easy: just choose one radio button or the other.
</EM></FONT></STRONG></P>
<P><STRONG><FONT COLOR="#000066"><EM>
Unkudos to the Second Cup cybercafe in Halifax.  The Start menu has a
special item for Telnet but when you choose it, you get a dialog saying,
"this operation is prohibited by the system administrator".  -- Mike
</EM></FONT></STRONG></P>
<P><STRONG>
you call yourself the "answer guy" and all you know how to be is a
sarcastic little bastard..
</STRONG></P>
<P><STRONG><FONT COLOR="#000066"><EM>
If you saw the hundreds of messages we receive every month and the high
percentage of them that are questions totally outside our scope, you
might become a sarcastic little bastard too.  -- Mike
</EM></FONT></STRONG></P>
<ol>
<li> He didn't call himself The Answer Guy -- that's what Marjorie named the
column, and the title clung to him.  It's an okay title but there could
be better ones - none of which stuck long enough to be worth changing the
column title.

<li> It's a whole bunch of people now - has been for months - so it's The
Answer Gang.  Which member of the Gang are you whining about? 
<IMG SRC="../gx/dennis/smily.gif" ALT=":)" 
		height="24" width="20" align="middle">

<br>
I'll assume Jim Dennis, for the moment.


<li>"all he knows how to be is..." - yeah, that's why he has a well paying
job in the Silicon Valley, and a published book (from a normal publishing
house, so yes, it's been spell checked), and speaking engagements at
conferenees.  Because he doesn't know anything.
</ol>
<P>
We all have our good days, and our sarcastic days, and the point of our
column is that we're real people, answering in just the same way we would
if you asked us at the mall while we were buying a box of the latest
Linux distro.
</P>
<P>
A particular thing to note is very few of us are Windows people.  Most of
us not at all - and others have had bad real-life experiences with the OS
you presently favor.  So not everyone will be cheer and light towards things
we consider to be poor sysadmin practices.  Especially things which would
be poor sysadmin practices even in an all Microsoft corporate netcenter.
</P>
<P>
At least two of us have enough WIndows experience to attempt answers in
that direction -- but this is the LINUX Gazette.  If your questions are
not about LINUX at least partially, then we really didn't want to hear
from you... so you should be glad you got any answer at all...
</P>
<P>
... and curiously enough, some Windows people have gotten real answers
for themselves in Linux documents once we point them the right way.
</P>
<P>
The practice of running an open service needs more care than just "clicking
Yes" on the NT service daemon, and some of these services only make sense
in a locked up environment.
</P>
<P>
Many but not all of The Answer Gang feel that telnet is now one such service.
By mailing us you ask our opinion, and that opinion is real, so we say it.
You do not have to like our opinions.  We don't have to like yours.  We
can still share computing power.
</P>
<P align="center">
<em>A free society is one where it is safe to be unpopular.</em>
</P>
<P><STRONG>
you make yourself seem very unintelligent to me and
have you ever heard of "If you can't say anything nice.don't say it at all?"
</STRONG></P>
<P>
As if calling us a bastard is nice, yet you bothered to say <EM>that</EM>.  You know
absolutely nothing of the parentage of any member of this group unless you
read our Bios (<A HREF="../issue67/tag/bios.html"
	>http://www.linuxgazette.com/issue67/tag/bios.html</A>) ...
</P>
<P>
... and we know that you have not because you only speak to one person.
</P>
<P>
Parentage (or lack of one) doesn't necessarily lead to being technologically
clued, but having technical or scientifically inclined parents seems to help.
</P>
<P><STRONG>
Apparently not. The question Nellie asked was a valid one. Too bad she does
now all the mumbo jumbo computer jargon...maybe the next time you should self
proclaim yourself as the "Smart-ass Guy" instead.
Miriam Brown
</STRONG></P>
<P>
I believe "curmudgeon" is the term you're looking for, and yes, Jim Dennis
labels himself to be one.  Proudly.
</P>
<P>
Interestingly, a querent this month has asked where to read up on the techy
mumbo jumbo words so they can learn more about Linux and speak more freely
with their geeky friends.  Our answers to that will actually be useful to
many readers.
</P>
<P>
Poor english is tolerated to a fair degree on the querent's side.
(that is, if we can't figure out what querents are saying, it's hard to
even <EM>try</EM> to answer them).  Each Answerer's personal style is mostly
kept - so some are cheerful, some are grumpy.
</P>
<P><STRONG>
PS...Don't answer guys usually use spell check?
</STRONG></P>
<P>
It is not required to know how to use a spell checker, in order to know how
to rebuild a kernel.  You have delusions of us being some glossy print
magazine like <EM>Linux Journal</EM>.  (ps.  Our host, SSC publishes that.  It
does get spell checked and all those nice things.  Go subscribe to it if
you like.  End of cheap plug.)
</P>
<P>
Nobody here is paid a dime for working on the <EM>Gazette</EM> specifically, so
our editorial time is better spent on link checking and finding correct
answers... er, well, we try... than spellos.  We have occasionally had
people complain about this point very clearly and loudly, but there is
not room in the publishing schedule for them to squish themselves in
between and still meet deadline.  We suggested that they make their own
site carry the past issue after fixes (our copyright allows this) but
the people have then always backed down and gone away.  We'd almost
certainly merge their repairs if they made some, but nobody has taken
up on that offer yet.  Oh well.  Let us know if you want to start the
Excellent Speller's Site - we'll cheer for you.  Maybe some other docs
in the <A HREF="http://www.linuxdoc.org/">Linux Documentation Project</A> (LDP) could stand a typo scrub too.
</P>
<P>
Oddly, many people read <EM>LG</EM> religiously because it's written in 
person to
person mode and doesn't spray gloss all over the articles and columns that
way.   You will get ecstatic excitement at successes and growling at bad
ways to do things and every emotion in between.
</P>
<P>
No, many of the querents don't spell check either, but we still answer
<EM>them</EM>.
</P>
<P>
I hope you enjoyed your time flaming, but we have people asking questions
about Linux to get back to.
</P>

<!-- end 4 -->
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<P> <A NAME="mailbag/5"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">"Those were the days"</FONT></H3>
Wed, 11 Jul 2001 14:20:42 -0500
<BR>Pete Nelson (<a href="mailto:gazette@ssc.com">pete.nelson from serversolved.com</a>)

<P>
I have this dream of contributing something wonderfully useful to the
Gazette, but it ain't going to happen today. . .
</P>
<P>
No, I noticed the ravings on The Back Page of issue 67, and had to send
you the lyrics of "Those were the days":
</P>
<h4>For the way Glen Miller Played</h4>
<p>. . .
<br>(It looks like the rest was pretty good up til the last verse)
<br> . . .
<br>Didn't need no welfare state
<br>Everybody pulled his weight
<br>Gee, our old LaSalle ran great 
<br>Those were the days.
</P>
<P>
But better yet, is the Simpsonized version --
</P>
<P>
For the way the BeeGees played
<br>Films that John Travolta made
<br>Guessing how much Elvis weighed
<br>Those were the days
</P>
<P>
And you knew where you were then
<br>watching shows like Gentile Ben
<br>Mister we could use a man like Sheriff Lobo again
</P>
<P>
Disco Duck and Fleetwood Mac
<br>Coming out of my eight-track
<br>Micheal Jackson still was black,
<br>Those were the days
</P>
<P>
Maybe next time I write in, I'll have something more useful.
</P>
<P>
--
Pete Nelson
</P>
<p><em>Thanks, Pete, glad we could amuse.  I think we need a linux version,
or maybe a BSD one... -- Heather</em></p>

<!-- end 5 -->
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<P> <A NAME="mailbag/6"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">RE: Linux Gazette Kernel Compile Article.</FONT></H3>
Wed, 1 Jan 1997 00:06:40 +0200
<BR>Zwane Mwaikambo (<a href="mailto:gazette@ssc.com">zwane from linux.realnet.co.sz</a>)


<!-- sig -->

<P>
Hi,
</P>
<P>
First i must commend you on providing a service to all the Linux users
out there trying to get started on rolling their own kernel. I would just
like to point out a few things i found somewhat confusing about your
article.
</P>
<P>
You compiled in "math emulation" support even though you have a CPU with a
built in maths co-processor, in this case the math emulation will never be
used and essentially wastes memory. secondly, you selected SMP support for
your uniprocessor (UP) system. This on some occasion can cause problems with
specific UP motherboards causing them not to boot or certain kernel modules
not loading, in addition to being slower and taking up more memory than a
non-SMP kernel. Also as you might want to break apart your build procedure
by using double ampersands. i.e. "make dep &amp;&amp; make bzImage &amp;&amp; make modules
&amp;&amp; make modules install ....."
</P>
<P>
That aside, it's great that you're willing to share your experiences and
knowledge with the rest of the Linux community.
</P>
<P>
Regards,
<br>Zwane
</P>

<!-- end 6 -->
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<P> <A NAME="mailbag/7"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">Parrallel processing</FONT></H3>
Tue, 3 Jul 2001 12:22:08 -0700
<BR>UCT Student - stvchu001 (<a href="mailto:gazette@ssc.com">stvchu001 from mail.uct.ac.za</a>)

<P><STRONG>
I would like to contact the uuthor of the above article which appeared
in the april 2001 edition of your magazine .
</STRONG></P>
<P>
The author's name in all our articles is a hyperlink to his e-mail
address.  Rahul Joshi's is <A HREF="mailto:jurahul@hotmail.com"
	>jurahul@hotmail.com</A> -- Mike
</P>

<!-- end 7 -->
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<P> <A NAME="mailbag/8"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">response to: Yet Another Helpful Email</FONT></H3>
Tue, 10 Jul 2001 17:39:19 -0700
<BR>Bryan Henderson (<a href="mailto:gazette@ssc.com">bryanh from giraffe-data.com </a>)

<P>
I was pleased to see a letter by Benjamin D Smith that compares
learning Windows to learning Unix by drawing a mental graph of the
respective learning curves, because I thought it would set straight
a lot of people who misuse the term "steep learning curve."
</P>
<P>
But then Smith went ahead and misused the term himself, in a way
wholly inconsistent with the picture he drew.
</P>
<P>
To set the record straight, allow me to explain what a learning
curve is, and in particular what a steep one is all about.
</P>
<P>
The learning curve is a graph of productivity versus time.  As time
passes, you learn stuff and your productivity increases (except in
weird cases).
</P>
<P>
Windows has a steep learning curve.  You start out useless, but with
just a little instruction and messing around, you're already writing
and printing documents.  The curve rises quickly.
</P>
<P>
Unix has a very shallow learning curve.  You start out useless, and
after a day of study, you can still do just a little bit.  After
another day, you can do a little bit more.  It may be weeks before
you're as productive as a Windows user is after an hour.
</P>
<P>
Smith's point, to recall, was that the Windows learning curve, while
steep, reaches a saturation point and levels off.  The Unix curve,
on the other hand, keeps rising gradually almost without bound.  In
time, it overtakes the Windows curve.
</P>
<P>
--
Bryan Henderson
</P>

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<P> <A NAME="mailbag/9"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">anser guy</FONT></H3>
Wed, 18 Jul 2001 11:57:36 -0700 (PDT)
<BR>Heather (<a href="mailto:gazette@ssc.com">star from betelgeuse.starshine.org</a>)

<P><STRONG>
Are you still the answer guy, and do you still answer questions? If so, I
have one that's been bugging me for a year now. Just let me know,
</STRONG></P>
<P><STRONG>
Thanks!
</STRONG></P>
<P>
It's an Answer Gang now.  Jim Dennis is still one of us.
</P>
<P>
We answer <EM>some</EM> of the hundred of linux questions we get every month.
Questions which are not about Linux get laughed about, but have a much lower
chance of ever geeteting an answer.  They <EM>might</EM> be answered in a linux
specific way.
</P>
<P>
So if you've a linux question, send it our way 
<IMG SRC="../gx/dennis/smily.gif" ALT=":)" 
		height="24" width="20" align="middle">
</P>

<!-- end 9 -->
<a name="gaz"></a>
<P> <hr> <P>
<!-- =================================================================== -->
<center><H3><font color="maroon">GAZETTE MATTERS</font></H3></center>
<P> <HR> <P>
<!--====================================================================-->

<!-- BEGIN GAZETTE MATTERS -->

<UL>
<!-- index_text begins -->
<li><A HREF="#gaz/1"
	><strong>Mistake</strong></a>
<li><A HREF="#gaz/2"
	><strong>An lgbase question</strong></a>
<li><A HREF="#gaz/3"
	><strong>About which list is which</strong></a>
<li><A HREF="#gaz/5"
	><strong>Re: email distribution of the Gazette?</strong></a>
<!-- index_text ends -->
</UL>
<!--     .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.     -->
<P> <A NAME="gaz/1"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">Mistake</FONT></H3>
Thu, 28 Jun 2001 18:16:59 +0100
<BR>Xavier (<a href="mailto:gazette@ssc.com">Xavier from aemiaif.lip6.fr</a>)

<P>
I just look at your issue 41 (I know that is not really recent ...) but
in the article of Christopher Lopes which is talking about CUP, there is
a mistake...
</P>
<P>
I tested it and I see that it didn't walk correctly for all the cases. In
fact it is necessary to put a greater priority to the operator ' - ' if not,
we have 8-6+9 = -7 because your parsor realizes initially (6+9 = 15) and
after (8-15= -7). To solve this problem it is enough to create a state
between expr and factor which will represent the fact that the
operator - has priority than it +.
</P>
<P>
Cordially.
</P>
<P>
Xavier Prat.
MIAIF2.
</P>
<p>See attached <a href="misc/mailbag/issue41-fix.CUP.txt">misc/mailbag/issue41-fix.CUP.txt</a></p>

<!-- end 1 -->
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<P> <A NAME="gaz/2"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">An lgbase question</FONT></H3>
Mon, 2 Jul 2001 12:10:20 -0500
<BR>Chris Gianakopoulos (<a href="mailto:gazette@ssc.com">pilolla from gateway.net</a>)

<P><STRONG>
I want to install all of the newest Linux Gazette issues on one of our
Linux machines at work.  Sounds easy enough.
</STRONG></P>
<P><STRONG>
Consider that I have approximately 12 month's worth of Linux Gazette
issues AND each lgbase that I download with each issue.  Is the lgbase
file cumulative?  In other words, can I install the latest and greatest
lgbase, and then install (you know -- copy them to the LDP/LG directory
tree) all of the Linux Gazette issues.
</STRONG></P>
<P>
Yes.  There's only one lg-base.tar.gz, which contains shared files for all
the issues.  So you always want the latest lg-base.tar.gz.
</P>
<P>
However, once you've installed it, you don't have to download it again
every month.  Instead, you can download the much smaller lg-base-new.tar.gz,
which contains only the files that are new or changed since the previous
issue.  But if you miss a month, you'll need to download the full
lg-base.tar.gz again to get all the accumulated changes.
</P>
<P>
Always untar lg-*.tar.gz files in the same directory each month.  They will
unpack into a subdirectory lg/ with everything in the correct location.
</P>
<P><STRONG>
Thanks Mike,
</STRONG></P>
<P><STRONG>
You've saved me a lot of time.  The system (<A HREF="http://www.suse.com/">SuSE</A> 7.0 distribution) had an
up-to-date base up until March last year. Your answer saved me lots of
untarring operations.  And yes, I do put the stuff in the same directory
each month on my home system.
</STRONG></P>
<P><STRONG>
Thanks for our fine magazine, and again keep up the good work (all of
you),
</STRONG></P>
<P><STRONG>
Chris G.
</STRONG></P>

<!-- end 2 -->
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<P> <A NAME="gaz/3"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">About which list is which</FONT></H3>
Mon, 16 Jul 2001 09:52:00 -0700
<BR>Hylton Conacher  (<a href="mailto:gazette@ssc.com">hylton from global.co.za</a>)

<P>
[Resent because Majordomo thought it was a command.  You have to watch that
word  s-u-b-s-c-r-i-b-e near the top of messages. -- Mike]
</P>
<P>
----- Forwarded ------
</P>
<P><STRONG>
Hi Heather,
</STRONG></P>
<P><STRONG>
Sorry, just another dumb newbie question. I have recently signed up to
the tag-admin list but not the tag list. I want  to be subbed to the Tag
list and as a result I have just tried to subscribe to tag by sending
the following to <A HREF="mailto:majordomo@ssc.com"
	>majordomo@ssc.com</A>:
</STRONG></P>
<P><STRONG><BLOCKQuote>
subscribe tag <A HREF="mailto:hylton@global.co.za"
	>hylton@global.co.za</A>
</BLOCKQuote></STRONG></P>
<P>
Given the pattern for the other one, I'm guessing that sending the word
</P>
<P>
subscribe
</P>
<P>
to the address
</P>
<P>
<A HREF="mailto:tag-request@ssc.com"
	>tag-request@ssc.com</A>
...should work too.
</P>
<P><STRONG>
I, as yet, haven't recd any notifications that a new Linux Gazette has
been added to the files area.
</STRONG></P>
<P>
For that, you don't want tag nor tag-admin, you want to send a note to
<A HREF="mailto:lg-announce-request@ssc.com"
	>lg-announce-request@ssc.com</A> and subscribe to lg-announce.  That doesn't
say much except that the gazette is posted.
</P>
<P>
What you will find here on tag-admin are precursor discussions;  talk about
what should or shouldn't get published, need to tweak deadlines, and some
other things that are either water-cooler talk or "infrastucture" matters.
</P>
<P><STRONG>
Do the announcements of the new Linux Gazettes come out on the TAG-Admin
list or only on Tag?
</STRONG></P>
<P>
Neither.
</P>
<P>
If you join the TAG list, you will be inundated with a large number of newbie
and occasional non-newbie computing questions, not all linux-related... and
a certain amount of spam that slips the filters, not all of it in English...
and a certain number of utterly dumb questions with no relation at all to
computing (apparently a side effect of the word "homework" being used so
often here).  I'd dare say most of the spam is not in English.  Since we
sometimes get linux queries in non-English languages we can't just chop
them off by character set from the list server, but they're easy to spot and
delete.
</P>
<P>
You will also see the answers flow by from members of the Gang, and efforts
to correct each other.  If you only visit the magazine once a month, you see
less answers, some of them get posted in 2c Tips, and they have been cleaned
up for readability.
</P>
<P>
So I can see reasons why someone who doesn't feel like answering questions
might want to join the TAG list and lurk, but I'm not sure which of these
you wanted.
</P>
<P><STRONG>
Puzzled.
</STRONG></P>
<P><STRONG>
Hylton
</STRONG></P>

<!-- end 3 -->
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<P> <A NAME="gaz/4"><HR WIDTH="40%" ALIGN="center"></A> <P>

<!-- sig -->

<P><STRONG>
Thank you Heather,
</STRONG></P>
<P><STRONG>
You as a member of TAG have certainly answered my questions.
</STRONG></P>
<P>
<IMG SRC="../gx/dennis/smily.gif" ALT=":D" 
		height="24" width="20" align="middle">
</P>
<P><STRONG>
There has been a message sent to <A HREF="mailto:majordomo@ssc.com"
	>majordomo@ssc.com</A> to unsub/scribe from
both the TAG and TAG-Admin lists as I do not want to receive idle
watercooler chat as I cannot reply immediately, in a watercooler
fashion, due to my countries telecoms monopolistic provider.
</STRONG></P>
<P><STRONG><FONT COLOR="#000066"><EM>
ob TagAdmin: if Mylton has no objection, this message will go in the mailbag
this month.
</EM></FONT></STRONG></P>
<P><STRONG>
Hylton has no objection so please FW to the necessary people provided
some idea is given of how to ascertain when a new Linux Gazette is
published.
</STRONG></P>
<P>
Send an email, with the subject containing a magic word which mailing list
software enjoys.... please take the slash out though... my sysadmin warns
me if I utter this word in too short a mail, the mail goes to majordomo's
owner and not to you.
</P>
<Pre>
subject:  sub/scribe
to:	<A HREF="mailto:lg-announce-request@ssc.com">lg-announce-request@ssc.com</A>

(body text)
sub/scribe

--
(optionally your sig file)
</Pre>
<P>
...mentioning it in the body text should be unnecessary.  That -- keeps
it from trying your sig as a command too.
</P>
<P>
The result will be your membership on a list which sees mail about once a
month, saying when the Gazette is posted.
</P>
<P>
Because you are in another country you might want to look at the Gazette
Mirrors listing and find a site which is closer to you.  Your bandwidth
cost might be the same but hopefully your download time won't cost as much.
<A HREF="../mirrors.html"
	>http://www.linuxgazette.com/mirrors.html</A>
</P>
<P>
Thx for your permission to publish 
<IMG SRC="../gx/dennis/smily.gif" ALT=":)" 
		height="24" width="20" align="middle">
</P>

<!-- end 4 -->
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<P> <A NAME="gaz/5"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/envelope.gif">
<FONT COLOR="navy">Re: email distribution of the Gazette?</FONT></H3>
Tue, 3 Jul 2001 15:28:31 -0700
<BR>Hylton Conacher (<a href="mailto:gazette@ssc.com">hylton from global.co.za</a>)

<P><STRONG><FONT COLOR="#000066"><EM>
Please direct me towards a place where I can sign up to receive the
Linux Gazette on a monthly or weekly basis when they become available.
</EM></FONT></STRONG></P>
<P><STRONG><FONT COLOR="#000066"><EM>
I would like this to be a free service.
</EM></FONT></STRONG></P>
<P><STRONG>
You don't "receive" Linux Gazette.  You read it on the web or download
the FTP files.  LG is published monthly on the first of the month, although
occasionally we have mid-month extra issues. -- Mike
</STRONG></P>
<P>
We do have an announce list, though.  Write to <A HREF="mailto:lg-announce-request@ssc.com"
	>lg-announce-request@ssc.com</A>
</P>
<P>
I suppose you could use the Netmind service (<A HREF="http://mindit.netmind.com"
	>http://mindit.netmind.com</A>) if
you don't like ours 
<IMG SRC="../gx/dennis/unsmily.gif" ALT=":(" 
		height="24" width="20" align="middle">
</P>
<P>
Sending large files via email, regularly, is really, really-really, an
incredibly bad idea.  Just come get it via ftp when it's ready!  Our ftp
site is free: <A HREF="ftp://ftp.ssc.com/pub/lg"
	>ftp://ftp.ssc.com/pub/lg</A>
</P>

<!-- end 5 -->
<!--              . . . . . . . . . . . . . . . . . . .              -->
<HR WIDTH="40%" ALIGN="center">

<P><STRONG><FONT COLOR="#000066"><EM>
Heather,
</EM></FONT></STRONG></P>
<P><STRONG><FONT COLOR="#000066"><EM>
Thank you for the response regarding my query.
</EM></FONT></STRONG></P>
<P><STRONG><FONT COLOR="#000066"><EM>
May I suggest that the service of email distribution of the gazettes be
investigated and provided to those people who sign up for them.
</EM></FONT></STRONG></P>
<P>
Please read our FAQ: we have considered it, and the answer is No.
</P>
<P>
Sending huge email attachments around is an undesirable burden on our own
mail servers as well as major MX relay points;
</P>
<P><STRONG><FONT COLOR="#000066"><EM>
I personally have made note of the ftp site but here in South Africa I
can only afford a dial-up connection the site has therefore been added
into a list to visit in the future. The problem comes in when I want to
know if there are any new tutorials on the ftp space since my last
visit. It would therefore be much more handy for me, and possibly
others, if they were allowed to request and start receiving the gazettes
via email.
</EM></FONT></STRONG></P>
<P>
You may subscribe to the announce list.  When you get the announcement,
visit the FTP site... or a local mirror.
</P>
<P><DL><DT>
There are many mirror sites in South Africa - please use one:
<DD><A HREF="../mirrors.html#south_africa"
	>http://www.linuxgazette.com/mirrors.html#south_africa</A>
</DL></P>
<P><STRONG><FONT COLOR="#000066"><EM>
Not everyone needs to receive it, just the ppl signed up to the
distribution list.
</EM></FONT></STRONG></P>
<P><STRONG><FONT COLOR="#000066"><EM>
Please?
</EM></FONT></STRONG></P>
<P>
Please use the internet's resources wisely.  The whole thing is clogged
up enough, without help from us.
</P>

<STRONG><FONT COLOR="#000066"><EM>
<P>
Hi Heather,
</P>
<P>
OK, OK, I give up.  It was just a suggestion.
</P>
<P>
The Internet is so slow already what with video clips going via email
that I do not feel anything in using a little of it to increase my
knowledge.
</P>
<P>
I have signed up to the announcement list and will use a mirror closest
to me.
</P>
<P>
Is it possibly possible to use Linux wget feature to retrieve all the
bulletins if I so wanted?
</P>
<P>
Hylton
</P>
</EM></FONT></STRONG>

<p>Yes!  That's the spirit! -- Heather</p>

<!-- end 6 -->
<P> <hr> </p>
<!-- *** BEGIN copyright *** -->
<H5 align="center">This page edited and maintained by the Editors
	of <I>Linux Gazette</I> 
<a href="http://www.linuxgazette.com/copying.html"
	>Copyright &copy;</a> 2001
<BR>Published in issue 69 of <I>Linux Gazette</I> August 2001</H5>
<H6 ALIGN="center">HTML script maintained by
	<A HREF="mailto:star@starshine.org">Heather Stern</a> of
	Starshine Technical Services,
	<A HREF="http://www.starshine.org/">http://www.starshine.org/</A> 
</H6>
<!-- *** END copyright *** -->
<H4 ALIGN="center">"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="#distro">Distro News</A>
<li><a HREF="#general">News in General</a>
<li><a HREF="#software">Software Announcements</a>
</ul>
</td></tr></table>

<STRONG>Selected and formatted by  <A HREF="mailto:michael.conry@softhome.net">Michael Conry</A>
and <A HREF="mailto:gazette@ssc.com">Mike Orr</A></STRONG>
</center>


<P> Submitters, send your News Bytes items in 
<FONT SIZE="+2"><STRONG>PLAIN TEXT</STRONG></FONT>
format.  Other formats may be rejected without reading.  You have been
warned!  A one- or two-paragraph summary plus URL gets you a better
announcement than an entire press release.





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

<H3><IMG ALT=" "   SRC="../gx/bolt.gif">
<font color="green">
August 2001 <I>Linux Journal</I>
</font>
</H3>

<IMG ALT=" "   SRC="misc/bytes/lj-cover88.png" WIDTH=200 HEIGHT=268
ALIGN="left" HSPACE="20">

<P> 
The August issue of <A HREF="http://www.linuxjournal.com/"><I>Linux
Journal</I></A> is on newsstands now.
This issue focuses on Platforms.  Click 
<A HREF="http://www.linuxjournal.com/lj-issues/issue88/index.html">here</A>
to view the table of contents, or 
<A HREF="http://www.linuxjournal.com/subscribe/index.html">here</A> 
to subscribe.

<P>
<FONT COLOR="green">All articles through December 1999 are available for
public reading at 
<A HREF="http://www.linuxjournal.com/lj-issues/mags.html">http://www.linuxjournal.com/lj-issues/mags.html</A></FONT>.  
Recent articles are available on-line for subscribers only at 
<A HREF="http://interactive.linuxjournal.com">
http://interactive.linuxjournal.com/</A>.  

<BR CLEAR="all">


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

<H3><IMG ALT=" "   SRC="../gx/bolt.gif">
<font color="green">
July/August 2001 <I>Embedded Linux Journal</I>
</font>
</H3>

<IMG ALT=" "   SRC="misc/bytes/elj-cover04.png" WIDTH=200 HEIGHT=268 
ALIGN="left" HSPACE="20">

<P> 
The July/August issue of 
<A HREF="http://embedded.linuxjournal.com/"><I>Embedded Linux Journal</I></A> 
has been mailed to subscribers.  This issue focuses on Platforms.  Click 
<A HREF="http://embedded.linuxjournal.com/magazine/issue04/">here</A>
to view the table of contents.  Articles on-line this month include
<A HREF="http://embedded.linuxjournal.com/magazine/issue04/4624/">Embedded Linux
on the PowerPC</A>, 
<A HREF="http://embedded.linuxjournal.com/magazine/issue04/4714/">Will It Fly? Working toward Embedded Linux Standards:
theELC's Unified Specification Plan</A>, 
<A HREF="http://embedded.linuxjournal.com/magazine/issue04/4773/">Boa: an
Embedded Web Server</A>,
and more.

<P> US residents can subscribe to <I>ELJ</I> for <STRONG>free</STRONG>; just
<A HREF="http://www.linuxjournal.com/subscribe/index.html">click here</A>.
Paid subscriptions outside the US are also available; click on the above link
for more information.  

<BR CLEAR="all">





<a name="distro"></a>
<p><hr><p>
<!-- =================================================================== -->
<center><H3><font color="green">Distro News</font></H3></center>


<P> <hr> <P> 
<!-- =================================================================== -->
<H3><IMG ALT=" "   SRC="../gx/bolt.gif">
<FONT COLOR="green">SuSE
</FONT>
</H3> 

<P> <a href="http://www.suse.de/en/">SuSE</a> Linux 
<a href="http://www.suse.de/en/produkte/susesoft/enterprise/index.html">
Enterprise Server</a> for
the 32-bit architecture by Intel was 
<a href="http://www.suse.de/en/news/PressReleases/mySAPcom.html">
awarded</a> the status "Generally
Available for mySAP.com". This certification now enables companies all
over the world to utilise 
<a href="http://www.mySAP.com/">mySAP.com</a> on SuSE Linux Enterprise Server
and take advantage of services and support from SAP AG.
For further information see <a href="http://www.sap.com/linux/">
http://www.sap.com/linux/</a>
<hr noshade width="20%">

<P>SuSE Linux, 
<a href="http://www.suse.de/en/news/PressReleases/firewall.html">
presented</a> a
new Linux solution for professional deployment at the LinuxTag expo in
Stuttgart, Germany. The "SuSE Linux Firewall on CD" offers 
protection for Internet-linked companies' mission-critical data and IT
infrastructure.
SuSE Linux Firewall is an application level gateway combining high
security standards of a hardware solution with the flexibility of a
software firewall. 
Instead of being installed on the hard disk, SuSE Linux Firewall is
so-called a live system that enables the operating system to be booted
directly from a read-only CD-ROM. Since it is impossible to manipulate
the firewall software on CD-ROM, the live system constitutes a security
gain.
The configuration files for the firewall, such as the ipchains packet
filter settings, are placed on a write-protected configuration floppy.


<a name="general"></a>
<p><hr><p>
<!-- =================================================================== -->
<center><H3><font color="green">News in General</font></H3></center>

<P> <hr> <P> 
<!-- =================================================================== -->
<H3><IMG ALT=" "   SRC="../gx/bolt.gif">
<FONT COLOR="green">Upcoming conferences and events 
</FONT>
</H3> 

<P> Listings courtesy <EM>Linux Journal</EM>.  See <EM>LJ</EM>'s
<A HREF="http://noframes.linuxjournal.com/events/">Events</A> page for the
latest goings-on.


<!-- *** BEGIN events table [this line needed by Linux Gazette events.py *** -->

<table cellpadding=5 border=0 width=100%>

<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>

<tr><td valign=top>
	<b>O'Reilly Open Source Convention</b><BR>
	<td valign=top>July 23-27, 2001<BR>San Diego, CA<BR>
	<A HREF="http://conferences.oreilly.com/" target=_blank>
	http://conferences.oreilly.com</A><BR>
	</td></tr>

<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>

<tr><td valign=top>
        <b>10th USENIX Security Symposium</b><BR>
        <td valign=top>August 13-17, 2001<BR>Washington, D.C.<BR>
        <A HREF="http://www.usenix.org/events/sec01/" target=_blank>
        http://www.usenix.org/events/sec01/</A><BR>
        </td></tr> 

<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>

<tr><td valign=top>
        <b>HP World 2001 Conference & Expo</b><BR>
        <td valign=top>August 20-24, 2001<BR>Chicago, OH<BR>
        <A HREF="http://www.hpworld.com" target=blank> 
        http://www.hpworld.com</A><BR>
        </td></tr>      

<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>

<tr><td valign=top>
        <b>Computerfest</b><BR>
        <td valign=top>August 25-26, 2001<BR>Dayton, OH<BR>
        <A HREF="http://www.computerfest.com/" target=_blank>
        http://www.computerfest.com</A><BR>
        </td></tr>

<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>

<tr><td valign=top> 
	<b>LinuxWorld Conference & Expo</b><BR>
	<td valign=top>August 27-30, 2001<BR>San Francisco, CA<BR>
	<A HREF="http://www.linuxworldexpo.com" target=blank>
	http://www.linuxworldexpo.com</A><BR>
	</td></tr>

<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>

<tr><td valign=top>
        <b>Red Hat TechWorld Brussels</b><BR>
        <td valign=top>September 17-18, 2001<BR>Brussels, Belgium<BR>
        <A HREF="http://www.europe.redhat.com/techworld" target=_blank>
        http://www.europe.redhat.com/techworld</A><BR>
        </td></tr>

<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>

<tr><td valign=top>
        <b>The O'Reilly Peer-to-Peer Conference</b><BR>
        <td valign=top>September 17-20, 2001<BR>Washington, DC<BR>
        <A HREF="http://conferences.oreilly.com/p2p/call_fall.html" 
	target=_blank>
        http://conferences.oreilly.com/p2p/call_fall.html</A><BR>
        </td></tr> 

<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>

<tr><td valign=top>
	<b>Linux Lunacy<br>Co-Produced by <i>Linux
	Journal</i> and Geek Cruises</b><BR>
        <A HREF="http://www.linuxjournal.com/lunacy/cruise.html" target=_blank>
        Send a Friend <i>LJ</i> and Enter to Win a Cruise!</A><BR> 
	<td valign=top>October 21-28, 2001<BR>Eastern Caribbean<BR>
	<A HREF="http://www.geekcruises.com/" target=_blank>
	http://www.geekcruises.com</A><BR>
	</td></tr> 

<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>

<tr><td valign=top>
        <b>LinuxWorld Conference & Expo</b><BR>
        <td valign=top>October 30 - November 1, 2001<BR>Frankfurt, Germany<BR>
        <A HREF="http://www.linuxworldexpo.de" target=_blank>
        http://www.linuxworldexpo.de</A><BR>
        </td></tr>

<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>

<tr><td valign=top>
        <b>5th Annual Linux Showcase & Conference</b><BR>
        <td valign=top>November 6-10, 2001<BR>Oakland, CA<BR>
        <A HREF="http://www.linuxshowcase.org/" target=_blank>
        http://www.linuxshowcase.org/</A><BR>
        </td></tr> 

<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>

<tr><td valign=top>
        <b>Strictly e-Business Solutions Expo</b><BR>
        <td valign=top>November 7-8, 2001<BR>Houston, TX<BR>
        <A HREF="http://www.strictlyebusinessexpo.com/" target=_blank>
        http://www.strictlyebusinessexpo.com</A><BR>
        </td></tr> 

<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>  

<tr><td valign=top>
        <b>LINUX Business Expo</b><BR>Co-located with COMDEX<br>
        <td valign=top>November 12-16, 2001<BR>Las Vegas, NV<BR>
        <A HREF="http://www.linuxbusinessexpo.com" target=_blank>
        http://www.linuxbusinessexpo.com</A><BR>
        </td></tr>

<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr>

<tr><td valign=top>
        <b>15th Systems Administration Conference/LISA 2001</b><BR>
        <td valign=top>December 2-7, 2001<BR>San Diego, CA<BR>
        <A HREF="http://www.usenix.org/events/lisa2001/" target=_blank>
        http://www.usenix.org/events/lisa2001</A><BR>
        </td></tr>  

<tr><td colspan=2><HR size=5 width=100% noshade align=center></td></tr> 


</table>
<!-- *** END events table [this line needed by Linux Gazette events.py *** -->




<P> <hr> <P> 
<!-- =================================================================== -->
<H3><IMG ALT=" "   SRC="../gx/bolt.gif">
<FONT COLOR="green">Teamware and Celestix to co-operate
</FONT>
</H3> 

<P> 
<a href="http://www.teamware.com/">
Teamware Group</a>, and 
<a href="http://www.celestix.com/">
Celestix Networks GmbH.</a>, a
supplier of Linux-based server appliances have 
<a href="http://www.teamware.com/pressreleases/celestix.htm">
signed</a> a global agreement
according to which 
<a href="http://www.teamware.com/linux/linux_office-fs.htm">
Teamware Office-99</a> for Linux groupware will be
distributed and sold with the Celestix 
"<a href="http://www.celestix.com/product_aries.php">
Aries</a>" micro servers. Supporting a
wireless standard the new system is the first wireless groupware server
offered for small businesses.


<P> <hr> <P> 
<!-- =================================================================== -->
<H3><IMG ALT=" "   SRC="../gx/bolt.gif">
<FONT COLOR="green">PostgreSQL: The Elephant Never Forgets
</FONT>
</H3> 
<P> 
<a href="http://www.opendocspublishing.com/">
Open Docs Publishing
</a> has announced today that they plan to ship their
sixth book entitled 
"<a href="http://www.opendocspublishing.com/entry.lxp?lxpe=92">
PostgreSQL: The Elephant Never Forgets</a>" by the first
week of August 2001. This title will include community version of 
<a href="http://www.postgresql.org/">
PostgreSQL</a>
version 7.1, the PostgreSQL Enterprise Replication Server (eRserver) and the
LXP application server. This will offer to companies the security of a
replication server, data backup services, disaster recovery, and business
continuity solutions previously limited to more costly commercial Relational
Database Management System (RDBMS) packages. Who could ask for more? 
The
book will fully document installation procedures, administration techniques,
usage, basic programming interfaces, and replication capabilities of
PostgreSQL. A complete reference guide will also be included.
The book is now 
<a href="http://www.opendocspublishing.com/entry.lxp?lxpe=92">
online</a> for development review and feedback.

<P> <hr> <P> 
<!-- =================================================================== -->
<H3><IMG ALT=" "   SRC="../gx/bolt.gif">
<FONT COLOR="green">Total Impact's new "briQ" network appliance
</FONT>
</H3> 

<P> 
<a href="http://www.totalimpact.com/">Total Impact</a>'s 
new network appliance computer, 
<a href="http://www.totalimpact.com/briQ.html">the briQ</a>
weighs in at 32 ounces, and has been 
<a href="http://www.totalimpact.com/june27.html">
selected</a> as 
<a href="http://www.ibm.com/">IBM</a>'s first 
<a href="http://www.chips.ibm.com/products/powerpc/linux/">PowerPC Linux</a> 
Spotlight
<a href="http://www.chips.ibm.com/products/powerpc/linux/linux-spotlight-briq.html">
feature product</a>. As a featured product, the briQ
and its benefits
are profiled in the June edition of IBM's Microprocessing and PowerPC Linux
website, and may be reviewed at the above link, or at Total Impact's
<a href="http://www.totalimpact.com/">website</a>.

<P> <hr> <P> 
<!-- =================================================================== -->
<H3><IMG ALT=" "   SRC="../gx/bolt.gif">
<FONT COLOR="green">LinuxWorld San Francisco to showcase embedded linux
solutions
</FONT>
</H3> 



<P>
<a href="http://www.idg.com/">IDG</a> 
<a href="http://www.idgworldexpo.com">World Expo</a> announced today that the
upcoming 
<a href="http://idg.com/www/events.nsf/EventsByProductLineForm?OpenForm&region=WW&product=LinuxWorld">
LinuxWorld Conference & Expo</a>, to be held August 28-30, 2001 at San
Francisco's Moscone Convention Center, will feature an Embedded Linux
Pavilion to educate attendees on the growing opportunities for Linux in
embedded computing.
The Pavilion will be sponsored by the 
<a href="http://www.embedded-linux.org/">
Embedded Linux Consortium (ELC)</a>, a
vendor-neutral trade association dedicated to promoting and implementing the
Linux operating system throughout embedded computing.   





<P> <hr> <P> 
<!-- =================================================================== -->
<H3><IMG ALT=" "   SRC="../gx/bolt.gif">
<FONT COLOR="green">Linux Links
</FONT>
</H3> 
<P>
<a href="http://www.thedukeofurl.org">
the Duke of URL</a>  has the following which may be of interest:
<ul>
<li>A <a href="http://www.thedukeofurl.org/reviews/systems/pogoveronap4">
review</a> of Pogo's sub-$1000 Pentium 4 Linux box, the Pogo Verona P4.
<li>A <a href="http://www.thedukeofurl.org/reviews/misc/xsentry15">
review</a> of Trustix XSentry Firewall 1.5 a high-end firewall for both
Linux and Windows produced by Trustix, the makers of Trustix Secure Linux.
The review covers the technology behind the firewall, installation,
configuration and more.
<li>A <a href="http://www.thedukeofurl.org/reviews/misc/promisehowtorh71">
HowTo</a> for the Promise FastTrak 66/100 on Red Hat Linux 7.1. which
covers the basics, including instructions for both the Promise driver 
and an open source one
<li>A <a href="http://www.thedukeofurl.org/reviews/video/abitsiluromx400">
review</a> of Abit's Siluro MX400 (based on the GeForce2 MX400 chipset)
The review covers benchmarks of both Linux and Windows performance.
<li>A <a href="http://www.thedukeofurl.org/reviews/misc/engarde101/">
review</a> of EnGarde Secure Linux 1.0.1, a unique brand of Linux with a
focus on security, e-commerce, and servers.
<li> A <a href="http://www.thedukeofurl.org/reviews/misc/yellowdog20">
review</a> of Yellow Dog Linux 2.0, which is based on Red Hat 7.0 and is
designed for the PowerPC platform, along with IBM's RS/6000 CPUs.
</ul>

<P> <a href="http://www.onlamp.com/">ONLamp.com</a> have an article on
<a href="http://www.onlamp.com/pub/a/apache/2001/06/19/apache_2.html">
migrating</a> a site from Apache 1.3 to 2.0.



<P>
The <a href="http://www.wsj.com">Wall Street Journal</a>'s 
<a href="http://www.ptech.wsj.com/">
Personal Technology</a> section has
<a href="http://ptech.wsj.com/archive/ptech-20010705.html">
News</a> of an unsettling nature about Windows XP registration, and a
<a href="http://slashdot.org/articles/01/07/05/1526255.shtml">
discussion</a>
of same on Slashdot.

<P>Other <a href="http://www.microsoft.com/">Microsoft</a> news indicates that
MS may
<a href="http://www.softwareuncovered.com/news/cgram-20010716.html#1">
help</a> create .NET for Linux. 
Microsoft told ComputerWire it would provide technical assistance to
<a href="http://www.ximian.com/">
Ximian Inc.</a> in its work on the 
<a href="http://www.ximian.com/tech/mono-index.php3">
Mono Project</a>, to develop a version of .NET
for Linux and Unix using open source development. 
This story was 
<a href="http://slashdot.org/article.pl?sid=01/07/16/128223&mode=nested">
highlighted</a> on
<a href="http://slashdot.org/">Slashdot</a>

<p> I don't want to seem MS obsessed, or anything ;-), but
<a href="http://lwn.net/">Linux Weekly News</a> has a
<a href="http://lwn.net/2001/0712/a/esr-viral.php3">critique</a> by Eric
Raymond on Microsoft's attacks on so-called "viral licences".

<p> More PostgreSQL news:
<A HREF="http://www.ca.postgresql.org/docs/hw_performance">PostgreSQL
Performance Tuning</A>.

<P> An OO approach to the classic 
<A HREF="http://groups.google.com/groups?ic=1&th=8a31b51350a5fcc9,1">
how to place eight queens on a chessboard so that none can attack any other</A>
problem, in Python.

<p>
If you are troubled by spam
<a href="http://combat.uxn.com/">http://combat.uxn.com/</a> might be of
interest to you.

<p> The TRS-80, the world's first laptop, 
<A HREF="http://www.sfgate.com/cgi-bin/article.cgi?file=/chronicle/archive/2001/07/22/BU160803.DTL">
is still in use</A>.

<p>
For the loser^H^H^H^H^Hgeek who has everything, 
<A HREF="http://slashdot.org/books/01/07/31/1412224.shtml">The Joy of Linux</A>
has tons of insider trivia.  As the 
<A HREF="http://slashdot.org/books/01/07/31/1412224.shtml">Shashdot review</A>
begins, "It's 2001. Do you love your operating system?"


<a name="software"></a>
<P> <hr> <P> 
<!-- =================================================================== -->
<center><H3><font color="green">Software Announcements</font></H3></center>


<P> <hr> <P> 
<!-- =================================================================== -->
<H3><IMG ALT=" "   SRC="../gx/bolt.gif">
<FONT COLOR="green">Linux NetworX launches ClusterWorX 2.0 cluster 
management software
</FONT>
</H3> 

<P>
<a href="http://www.linuxnetworx.com">Linux NetworX</a>, 
a provider of  Linux cluster computing solutions, has 
<a href="http://www.linuxnetworx.com/news/6.26.2001.48-Linux_NetworX_L.html">
announced</a> the launch
of its cluster management software 
<a href="http://www.linuxnetworx.com/products/clusterworx.html">
ClusterWorX 2.0</a>.
The latest version of ClusterWorX includes new features such as secure
remote access, thorough system and node monitoring and events, and easy
administrator customisation and extensibility. 


<P> <hr> <P> 
<!-- =================================================================== -->
<H3><IMG ALT=" "   SRC="../gx/bolt.gif">
<FONT COLOR="green">IBM database  news
</FONT>
</H3> 

<a href="http://www.ibm.com/">IBM</a>
has 
<a href="http://www1.internetwire.com/iwire/release_clickthrough?release_id=28404&category=Technology">
claimed</a> three database firsts:
Industry's First Database Software Supporting InfiniBand; Direct Access
File System; And New Itanium-Based SystemsDB2 Universal Database version
7.2. 
These have been demonstrated on 
<a href="http://www-4.ibm.com/software/data/db2/linux/">
DB2</a> running on Linux.

<P> <hr> <P> 
<!-- =================================================================== -->
<H3><IMG ALT=" "   SRC="../gx/bolt.gif">
<FONT COLOR="green">DocParse HTML to XML/SGML converter
</FONT>
</H3> 

<P><a href="http://www.commandprompt.com">Command Prompt, Inc.</a> 
have released 
<a href="http://www.commandprompt.com/products_DocParse.lxp">
DocParse 0.2.6</a>. DocParse is a
tool for technical authors who maintain a large amount of HTML based
documentation. DocParse will take any HTML document and convert it into a
valid DocBook XML/SGML document. From the XML or SGML format a user can
easily convert the document to XHTML, HTML, RTF(MS Word Format) and even
print ready postscript.  DocParse currently runs on x86 Linux only. They will
release for YellowDog Linux (PPC) and MacOS X shortly.  There are per seat
and subscription based licensing models available for immediate purchase.

<P> <hr> <P> 
<!-- =================================================================== -->
<H3><IMG ALT=" "   SRC="../gx/bolt.gif">
<FONT COLOR="green">StuffIt for Linux and Solaris ships
</FONT>
</H3> 

<P><a href="http://www.aladdinsys.com/">Aladdin Systems</a>, 
has shipped its award winning compression software, 
<a href="http://www.aladdinsys.com/products/stuffit/">
StuffIt</a> for  Linux and Sun's Solaris operating systems, making 
StuffIt available on Windows, Macintosh, Linux, and Solaris platforms.
StuffIt for Linux and Solaris can be used to 
create Zip, StuffIt, Binhex, MacBinary, Uuencode, Unix Compress, 
self-extracting archives for Windows or Macintosh platforms and it 
can be used to expand all of the above plus bzip files, gzip, arj, 
lha, rar, BtoAtext and Mime.
StuffIt for Linux can be 
downloaded at: 
<a href="http://www.stuffit.com/">www.stuffit.com</a>.

<P> <hr> <P> 
<!-- =================================================================== -->
<H3><IMG ALT=" "   SRC="../gx/bolt.gif">
<FONT COLOR="green">Great Bridge announces enhanced PostgreSQL 7.1 package
</FONT>
</H3> 

<P>
<a href="http://www.greatbridge.com/">
Great Bridge</a>, who today
<a href="http://www.greatbridge.com/about/press.php?content_id=63">
announced</a> the launch of 
<a href="http://www.greatbridge.com/shop/item.php?prod=11">
Great Bridge PostgreSQL 7.1</a>, the latest version of
the world's most advanced open source database. 
Great Bridge has packaged the release with a graphical installer, leading
database administration tools, professional documentation and an
installation and configuration support package to help application
developers quickly and easily deploy the power of PostgreSQL in advanced
database-driven applications.

<P> [There are at least two other entries about PostgreSQL in this News
Bytes column.  Can you find them?]

<P> <hr> <P> 
<!-- =================================================================== -->
<H3><IMG ALT=" "   SRC="../gx/bolt.gif">
<FONT COLOR="green">Timesynchro
</FONT>
</H3> 

<a href="http://www.timesynchro.com">Timesynchro.com</a>
have a free utility for download which can be used to manage your system
time. It is essentially a configuration script, using dialog and
some standard stuff, for netdate.
It incorporates a database of 100 servers to connect to, and the program
allows to test servers and add or delete them before using them for real
(some may no longer be available).

When you start 'timesynchro' it automatically chooses to start in German, but
selecting "Sprache" gives you the option to switch to English.
You get a rather easy menu structure to choose time servers.

<p> Thank you to Frank for summarising the website and features.

<P> <hr> <P> 
<!-- =================================================================== -->
<H3><IMG ALT=" "   SRC="../gx/bolt.gif">
<FONT COLOR="green">Surveyor Webcamsat
</FONT>
</H3> 

<P> 
<a href="http://www.surveyor.com/">
Surveyor Corporation</a>, makers of the  WebCam 32 webcam
software, has just announced a family of webcam servers that
addresses the need for increased control over web content.
Surveyor's 
Webcamsat (Web Camera Satellite Network -- Linux-based)
family of webcam servers give website operators a new level of control
over their streamed audio and video, allowing them the flexibility to
control multiple cameras with greater ease.


<P> <hr> <P> 
<!-- =================================================================== -->
<H3><IMG ALT=" "   SRC="../gx/bolt.gif">
<FONT COLOR="green">Kaspersky Labs anti-virus software
</FONT>
</H3> 

<P> The latest version of Kaspersky Anti-Virus affords customers the opportunity
of additionally installing a centralized anti-virus defense for file servers
and application servers operating on OpenBSD (version 2.8) and Solaris 8
(for Intel processors) systems, and also for exim e-mail gateways (one of
the five most popular e-mail gateways for Unix/Linux).
Development of this anti-virus package came about as a result of responding
to the needs of mid-size and large corporate customers using Unix, and
particularly Linux.

<P> Currently, Kaspersky Anti-Virus can be utilized on
Linux, FreeBSD, BSDi, OpenBSD, and Solaris operating systems, and also
contains a ready-made solution for integration into sendmail, qmail,
postfix, and exim e-mail gateways.  The package includes the scanner, daemon
and monitor anti-virus technology, and also includes automatic anti-virus
database updates via the Internet, an interactive parameter set-up shell and
a module for generating and processing statistic reports.

<P> <A HREF="http://www.kaspersky.com/">www.kaspersky.com</A> (Russia)



<!-- *** BEGIN copyright *** -->
<P> <hr> <P> 
<H5 ALIGN=center>
Copyright &copy; 2001, Michael Conry and 
the Editors of <A HREF="mailto:gazette@ssc.com"><I>Linux Gazette</I></A>.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR>
Published in Issue 69 of <i>Linux Gazette</i>, August 2001</H5>
<!-- *** END copyright *** -->

<center>
<H1><A NAME="answer">
	<img src="../../gx/dennis/qbubble.gif" alt="(?)" 
		border="0" align="middle">
	<font color="#B03060">The Answer Gang</font>
	<img src="../../gx/dennis/bbubble.gif" alt="(!)" 
		border="0" align="middle">
</A></H1> 
<BR>
<H4>By Jim Dennis, Ben Okopnik, Dan Wilder, Breen, Chris, and the Gang,
	the Editors of Linux Gazette... 
	and You!
<br>Send questions (or interesting answers) to
	<a href="mailto:linux-questions-only@ssc.com"'
		>linux-questions-only@ssc.com</a>
</H4>
<p><em><font color="#990000">There is no guarantee that your questions
	here will <b>ever</b> be answered.  Readers at confidential sites
	must provide permission to publish.  However, you can be published 
	anonymously - just let us know!
</font></em></p>
</center>

<p><hr><p>
<!--  endcut ======================================================= -->
<A NAME="tag/greeting"><HR WIDTH="75%" ALIGN="center"></A>
<H3 align="left"><img src="../gx/dennis/hbubble.gif"
        height="50" width="60" alt="(&para;) " border="0"
        >Greetings from Heather Stern</H3>
<!-- begin hgreeting -->
<p>
Hello, everyone, and welcome once more to the world of the Linux Gazette
Answer Gang.
</p><p>
The peeve of the month having been Non-Linux questions for a few too many
weeks in a row,  The Answer Gang has a new address.  Tell your friends:
</p><h3 align="center">
	linux-questions-only
</H3><p>	
...at ssc.com is now the correct place to mail your questions, and your
cool Linux answers.  It's our hope this will stop us from getting anything
further about pants stains, U.S. history, etc.  Cross platform matters with
Linux involved are still fine, of course.
</p><p>
For some statistics... there were over 31 answer threads, 25 tips (some
were mini threads) and over 600 messages incoming - and that's <em>after</em>
I deleted the spam that always leaks through. 200 more messages than last
month.  I'm pleased to see that the Gang is up to the task.
</p><p>
Now at this point I bow humbly and beg your forgiveness, that, being a 
working consultant with more clients than usual keeping me busy, I wasn't 
able to get all of these HTML formatted for you this time.  In theory
I can put a few as One Big Column but the quality is worse and we drive
the search engines crazy enough already.  I can definitely assure you that
next month's Answer Gang will have <em>tons</em> of juioy answers.
</p><p>
Meanwhile I hope I can mollify you with some of the Linux tools that have
been useful or relevant to me during my overload this month.
</p><p>
Mail configuration has been a big ticket item here at Starshine.  You may 
or may not be aware that by the time we go to press, the MAPS Realtime 
Blackhole List is now a paid service.  That means folks who have been 
depending on the RBL and its companion, the Dialup List, have to pay for 
the hard work of the MAPS team... and their bandwidth.   You can find other
sources of blacklisting information, or start enforcing your own policies
... but I would like to make sure and spread the news that they aren't 
going exclusively to big moneybags - file for hobbyist, non-profit or 
small site usage and you don't have to pay as much.  Maybe nothing.  But 
you do have to let them know if you want to use it, now.
</p><dl>
<dt>Mail Abuse Prevention System:
<dd>	<a href="http://www.mail-abuse.org/"
		>http://www.mail-abuse.org/</a>
</dl><p>
My fellow sysadmins had been seeing this coming for a long time.  Many 
actually prefer to know what sort of things are being blocked or not, 
anyway.  Censorship after all, is the flip side of the same coin. 
Choosing what's junk TO YOU is one thing, junking stuff you actually need
is entirely another.  If others depend on you then you have to be much more
careful.  Plaintext SMTP isn't terribly secure but it's THEIR mail, unless
you have some sort of contract with them about it.
</p><p>
So, I've been performing "Sherriff's work" for at least one client for a 
long while now anyway - just tweaking the filter defenses so that the kind of
spam which gets in, stays out next time.  There's a fairly new project on 
Sourceforge called Razor, which aims for anti-spam by signatures, the same 
way that antivirus scanners check for trojans and so on.  I haven't had time
to look into it, but I think they're on the right track.
</p><dl>
<dt>Razor:
<dd>	<a href="http://razor.sourceforge.net/"
		>http://razor.sourceforge.net/</a>
</dl><p>
Procmail (my favorite local delivery agent) has this great scoring mechanism;
it can help, or it can drive you crazy (depending on whether you grok their
little regex language - I like it fine).  I definitely recommend taking a
look at "junkfilter" package of recipes for it even if you are planning to
roll your own.  The best part is that it is <strong>not</strong> just one
big recipe - it's a bunch of them, so you can choose which parts to apply.  
</p><p>
Do make sure you have at least version 3.21 of procmail though. It's actually
gotten some improvement this month.
</p><dl>
<dt>Procmail:
<dd>	<a href="http://www.procmail.org/"
		>http://www.procmail.org/</a>
</dl><dl>
<dt>Junkfilter:
<dd>	<a href="http://junkfilter.zer0.org/"
		>http://junkfilter.zer0.org/</a>
</dl><p>
Folks who hate this stuff can try Sendmail's milters, Exim's filtering 
language, or possibly, do it all at the mail clients after the mail has
been delivered to people.
</p><p>
Whether your filters are mail-client, local-delivery, or MTA based, making
them sanity check that things are coming really to you, and from addresses
that really exist, can have a dramatic improvement.  The cost is processing
power and often, a certain amount of network bandwidth, but if you're really
getting hammered, it's probably worth it.  Besides if my 386 can deal with
just plain mail your PentiumIII-700 can actually do some work for a living
and probably not even notice, until your ethernet card starts complaining.
More on that 386 in a bit...
</p><p>
I've got a client who just switched from University of Washington's IMAP
daemon over to Courier.  The Courier MTA is just terrible (we tried, but
ended up thoroughly debugging a sendmail setup instead, and the system is
MUCH happier).  But the IMAP daemon itself is so much better it's hard
to believe.  He's convinced that it is more than the switch to maildirs
that makes it so incredibly fast.   He does get an awful lot of mail, so
I suspect Maildirs is what made the difference noticeable.  We may never 
know for sure.
</p><dl>
<dt>Courier-IMAP:
<dd>	<a href="http://www.inter7.com/courierimap/"
		>http://www.inter7.com/courierimap/</a>
</dl><p>
The world of DNS is getting more complicated every month, and slower.  
This has been clearly brought to light for me by two things - my client
at last taking over his own destiny rather than hosting through an ISP,
and my own mail server here at Starshine.
</p><p>
It used to be that there was only one choice for DNS, so ubiquitous
it's called "the internet name daemon" - BIND, of course.  And I'm very 
pleased to see that its new design seems to be holding up.  Still it has
the entire kitchen sink in it, and that makes it very complicated for 
small sites, even though there are a multitude of programs out there
to help the weary sysadmin.
</p><p>
A bunch of folks - including some among the Gang - really enjoy djbdns, 
but you have to buy into DJ Bernstein's philosophy about some things in 
order to be comfortable with it.  Its default policies are also a bit 
heavy handed about reaching for the root servers, which are, of course,
overloaded.  Still it's very popular and you can bet the mailing list 
folks will help you with it.
</p><dl>
<dt>djbdns:
<dd>	<a href="http://cr.yp.to/djbdns.html"
		>http://cr.yp.to/djbdns.html</a>
</dl><p>
However, his stuff (especially his idea of configuration files and "plain
english" in his docs) gives me indigestion, so I kept looking.  There are so
many caching-only nameservers I can't count them all.  It's a shame that
freshmeat's DNS category doesn't have sub categories for dynamic-dns, 
authoritative, and caching only, because that sure would make it easier 
to find the right one for the job.
</p><p>
However, I did find this pleasant little gem called MaraDNS.  It was 
designed first to be authoritative <em>only</em>, uses a custom string
library, and is trying to be extra careful about the parts of the DNS spec
it implements.  It was also easy to set up; zone files are very readable.
It looks like the latest dev version allows caching too... though whether
that's a creeping-feature is a good question.
</p><dl>
<dt>MaraDNS:
<dd>	<a href="http://www.maradns.org/"
		>http://www.maradns.org/</a>
</dl><p>
For years I've been pretty proud that we can run our little domain on a
386.  (Ok, we are cheating, that's not the web server.)  But I could just
<strong>kick myself</strong> for forgetting to put a DNS cache on it 
directly.  So the poor thing has been struggling with the evil internet's
timeouts lately and bravely plugging on...  occasionally sending me "sorry
boss, I couldn't figure out where to send it" kind of notes.  (No, it's not
qmail. I'm translating to English from RFC822-ese.) 
</p><p>
So I look at the resolv.conf chain.  No local cache.  What was I thinking?
(or maybe: What?  Was I thinking?  Obviously not.)
</p><p>
I tried pdnsd, because I liked the idea of a permanent cache... much more 
like having squid between you and the web, than just having a little memory
buffer for an hour or two.
</p><p>
However, the binary packages didn't work.  I wasn't going to compile it 
locally at the 386.  I'll get to reading its source maybe, but if anyone 
has successful experiences with it, I'd enjoy seeing your article in the 
<em>Gazette</em> someday soon.  I don't think I've tried very hard yet, 
but I had hoped it would be easier.
</p><p>
Meanwhile I had no time left and Debian made it a snap to have bind in cache
only mode.  Resolutions during mail seem to be much happier now.
</p><dl>
<dt>pdnsd:
<dd>	<a href="http://home.t-online.de/home/Moestl/"
		>http://home.t-online.de/home/Moestl/</a>
</dl><p>
There are also more mailing list managers out there than plants in my garden.
I've got a big project for a different client where the "GUI front end" is 
being dumbed down for the real end users, and I get to cook up a curses front 
end in front of the real features, for the staff to use.  It's very customized
to their environment.  I do hope they like it.
</p><p>
If you're working on a mailing list project, I beg, I plead, try and have 
something in between the traditional thrashing through pools of text files, 
and the gosh-nobody-wants-security-these-days web based administration.   
That way I can take less time to make the big bucks, and folks are a little 
bit happier with Linux. 
</p><p>
However, if you have in mind to do anything of the sort on your own, and you
prefer to work with shell scripts, I recommend Dialog.  Make sure you get a
recent version though.  There are a gazillion minor revisions and brain damaged
variants like whiptail.  Debian seemed to have the newest and most complete
amongst the distros I have lying around, so I ended up grafting its version
into another distro.  But, I finally tripped across a website for it that 
appears to be up to date. Use the "home" link to read of its muddied past.
</p><dl>
<dt>Dialog:
<dd>	<a href="http://www.AdvancedResearch.org/dialog/left-frame.html"
		>http://www.AdvancedResearch.org/dialog/left-frame.html</a>
</dl><p>
Lastly, Debian potato for Sparc isn't nearly as hard as I thought it was
going to be, but configuring all those pesky services on a completely fresh
box, that's the same pain every time.  It wouldn't be, if every client had
the same network plans, but - you know it - they don't!
</p><p>
I also had no ready Sparc disc 1, but a pressing need to get it, and my link
is not exactly the world's speediest.
</p><p>
Debian's pseudo image kit is a very strange and cool thing.  It's a bit clunky
to get going - you need to fetch some text files to get it started, and tell
it what files are actually in the disc you're going to put together.  But, 
once you've fed it that, it creates this "dummy" image which has its own 
padding where the directory structures will go, amd the files go in between. 
If some of them don't make it, oh well.  But you can get them from anywhere
on the mirror system ... much closer to home, usually,  Leave the darn thing 
growing a pseudo image overnight, then come back the next day and run rsync
against an archive site that allows rsync access to its official Debian CDs.
Instead of a nail-biting 650 MB download, 3 to 20 MB or so of bitflips and
file changes  If you either can't handle 650 MB at a time anyway, or like 
the idea of the heavy hit on your bandwidth allocation just being that last
clump of changes, it's a very good thing.
</p><p>
All it needs now is to be even smarter, and programmatically be able to 
fetch newer copies of the packages, then compose a real directory structure 
that correctly describes the files.  If someone could do that, you'd only
have to loopback mount the pseudoCD and re-generate Packages files, to 
have a current- instead of an Official disc, including all those security 
fixes we need to chase down otherwise.  Making it bootable might be more
tricky, but I'd even take a non-bootable one so I can give clients a 
mini-mirror site just by handing them a CD.
</p><dl>
<dt>Debian CD images information site:
<dd>	<a href="http://cdimage.debian.org/"
		>http://cdimage.debian.org/</a>
</dl><p>
So, I hope some of you find this useful.  I'm sure I'll see a number of 
you, and possibly some other members of the Answer Gang, at LinuxWorldExpo.  
</p><p>
'Til next time -- Heather Stern, The Answer Gang's Editor Gal
</p>
<!-- end hgreeting -->
<center>
<H1><A NAME="tips"><IMG ALIGN=MIDDLE ALT="" SRC="../gx/twocent.jpg">
More 2&cent; Tips!</A></H1> <BR>
<!-- BEGIN tips -->

Send Linux Tips and Tricks to <A HREF="mailto:gazette@ssc.com">gazette@ssc.com</A></center>
<UL>
<!-- index_text begins -->
<li>Subscribe to Tech tips from
	<A HREF="http://noframes.linuxjournal.com/subscribe/lja-sub.html"
		><I>Linux Journal's</I> Weekly News Notes</A>
</ul>
<ul>
<li><A HREF="#tips/2"
	><strong>bin/cue - iso files</strong></a>
<li><A HREF="#tips/3"
	><strong>Segmentation Faults -- At odd times.</strong></a>
<li><A HREF="#tips/4"
	><strong>editing shell scripts</strong></a>
<li><A HREF="#tips/5"
	><strong>2.2.20 kernel?</strong></a>
<li><A HREF="#tips/6"
	><strong>Linux on Sun Sparc??</strong></a>
<li><A HREF="#tips/7"
	><strong>Routing Mail</strong></a>
<li><A HREF="#tips/8"
	><strong>Command to read CMOS from running Linux system</strong></a>
<li><A HREF="#tips/9"
	><strong>linux ftp problem</strong></a>
<li><A HREF="#tips/10"
	><strong>Self extracting shell script</strong></a>
<li><A HREF="#tips/11"
	><strong>Cannot Format Network Drive</strong></a>
<li><A HREF="#tips/13"
	><strong>Wu-FTP and Linux Newbie</strong></a>
	A source of confusion.
<li><A HREF="#tips/14"
	><strong>Root Password</strong></a>
<li><A HREF="#tips/15"
	><strong>RH7.1 switch to KDE login as default</strong></a>
<li><A HREF="#tips/16"
	><strong>3d linux</strong></a>
<!-- index_text ends -->
</UL>
<!--     .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.     -->
<P> <A NAME="tips/2"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">bin/cue - iso files</FONT></H3>
Thu, 21 Jun 2001 12:46:24 +0000
<BR>Andrew Higgs (<a href="mailto:linux-questions-only@ssc.com">The Answer Gang</a>)

<P>
Question From: "M.Mahtaney" &lt;mahtaney from pobox.com&gt;
</P>
<P><STRONG><BLOCKQuote>
hi james
</BLOCKQuote></STRONG></P>
<P><STRONG>
i came across your website while looking for some help on file
compression/conversion
</STRONG></P>
<P><STRONG>
i downloaded an archive in winrar format - which then decrompressed to bin/cue
files
</STRONG></P>
<P><STRONG>
i'm not sure what to do with that now - i've converted it to an iso file, but
i need to basically open it up to gain access to the application that was
downloaded.
</STRONG></P>
<P><STRONG>
i'm a little lost on how to do that - can you help?
</STRONG></P>
<P><STRONG>
thanks,
mgm.
</STRONG></P>
<P>
Hi MGM,
</P>
<P>
Have you tried to mount the iso image and copy the files out? There maybe
another way but this worked for me.
</P>
<P><CODE>
mount -o loop -t is09660 file.iso /mnt
<br>ls /mnt
</CODE></P>
<P>
should then give a list of the files in the iso image.
</P>
<P>
Hope this helps.
</P>
<P>
Kind regards
Andrew Higgs
</P>

<!-- end 2 -->
<!--     .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.     -->
<P> <A NAME="tips/3"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Segmentation Faults -- At odd times.</FONT></H3>
Wed, 18 Jul 2001 15:03:33 -0700
<BR>Mike Orr (<a href="mailto:linux-questions-only@ssc.com">The Answer Gang</a>)

<P>
Question From: "Jon Coulter" &lt;jon from alverno.org&gt;
</P>
<P><STRONG>
I've recently upgraded the ram on my linux box in an attempt to wean some of
the memory problems that have been occurring
</STRONG></P>
<P>
What were the previous problems.  Just running out of memory?  Or other
things.
</P>
<P><STRONG>
, and now get "Segmentation
Fault"'s on almost every program about 80% of the time (if I keep trying and
keep trying to run the program, it eventually doesn't Segmentation Fault for
one time... sometimes then segmentation faulting later in its execution). My
question is: Is there anything I can do about this?!? But seriously, is
there any chance that a kernel upgrade would help fix this (my current
kernel is 2.4.2)? I just don't understand why a memory <EM>upgrade</EM> would cause
problems like this. I've run memtest86 test on the ram to ensure that it
wasn't corrupted at all.
</STRONG></P>
<P>
Frequent segfaults at random times usually indicate a hardware problem,
as you suspected.  A buggy kernel or libraries can throw segfaults left and
right too, but if you didn't install any software at the time the faults
started occurring, that rules that out.
</P>
<P>
Does <TT>/etc/lilo.conf</TT> have a "MEM=128M" number or something like that in it?
Some BIOSes require this attribute to be included, other's don't.  But if
it's specified, it must be correct.  Especially, it must not be larger
than the amount of RAM you have: otherwise it <EM>will</EM> segfault all over the
place and you'll be lucky to even get a login prompt.  Remember to run
lilo after changing lilo.conf.
</P>
<P>
Try taking out the memory and reseating it.  Also check the disks: are the
cables all tight and the partitions in order?  Since memory gets swapped to
disk if swap is enabled, it's possible for disk problems to masquerade as
memory problems.
</P>
<P>
If you put back your old memory, does the problem go away?  Or if you're
mixing old and new memory, what happens if you remove the old memory?
Are the two types of memory the same speed?  Hopefully the faster memory
will cycle down to the slower memory, but maybe the slower memory isn't
catching up.  What happens if you move each memory block to a different
socket?
</P>
<P>
I'm running 2.4.0.  There are always certain evil kernels that must be
avoided, but I don't remember any such warnings for the 2.4 kernels.
Whenever I upgrade, I ask around about the latest two stable kernels, and
use whichever one people say they've had better experiences with.
</P>
<P>
Good luck.  Random segfaults can be a very irritating thing.
</P>
<HR width="10%" align="center"><P>
More From:  Ben Okopnik (<a href="mailto:linux-questions-only@ssc.com">The Answer Gang</a>)

</P>
<P>
Take a look at the Sig 11 FAQ: &lt;<A HREF="http://www.bitwizard.nl/sig11/&gt"
	>http://www.bitwizard.nl/sig11/&gt</A>;.
</P>

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<P> <A NAME="tips/4"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">2c tip : editing shell scripts</FONT></H3>
Tue, 24 Jul 2001 09:24:02 -0400 (EDT)
<BR>Matt Willis (<a href="mailto:linux-questions-only@ssc.com">willis_matthew from yahoo.com</a>)

<P>
For shell scripts it's a common error to accidentally include a space
after the line-continuation character. This is interpreted as a
literal space with no continuation; probably not what you want. Since
spaces are invisible, it can also be a hard error to spot. If you use
emacs, you can flag such shell script errors using fontification. Add
this code to your ~/.emacs file:
</P>
<pre>
;;; This is a neat trick that makes bad shell script continuation
;;; marks, e.g. \ with trailing spaces, glow bright red:
(if (eq window-system 'x)
  (progn
    (set-face-background 'font-lock-warning-face "red")
    (set-face-foreground 'font-lock-warning-face "white")
    (font-lock-add-keywords 'sh-mode
      '(("\\\\[ \t]+$" . font-lock-warning-face)))
  )
)

</Pre>
<p>Matt Willis</P>
<HR width="10%" align="center"><P>
More From: Dan Wilder (<a href="mailto:linux-questions-only@ssc.com">The Answer Gang</a>)
</P>
<P>
And in vi,
</P>
<Pre>:set list</Pre>
<P>
reveals all trailing spaces, as well as any other normally
non-printing characters, such as those troublesome leading tabs
required in some lines of makefiles, and any mixture of tab-indented
lines with space-indented lines you might have introduced into Python
scripts.
</P>
<Pre>:set nolist</Pre>
<P>
nullifies the "list" setting.
</P>
<HR width="10%" align="center"><P>
More From: Ben Okopnik (<a href="mailto:linux-questions-only@ssc.com">The Answer Gang</a>)

</P>
<P>
Good tip, Matt! I'll add a bit to that: if you're using "vi", enter
</P>
<Pre>:set nu list</Pre>
<P>
in command mode to number all lines (useful when errors are reported),
show all tabs as "^I", and end-of-lines as "$". Extra spaces become
obvious.
</P>
<P>
In editors such as "mcedit", where selected lines are highlighted,
start at the top of the document, begin the selection, and arrow (or
page) down. The highlight will show any extra spaces at line-ends.
</P>

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<P> <A NAME="tips/5"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">2.2.20 kernel?</FONT></H3>
Thu, 19 Jul 2001 18:34:21 -0400
<BR>Heather Stern (<a href="mailto:linux-questions-only@ssc.com">The Answer Gang</a>)

<p>
Question From: Ben Okopnik
</p>

<P>
Where can I get one? I've looked at kernel.org, and they only go up to
.19...
</P>
<P>
Ben
</P>
<P><STRONG>
Glad you asked, Ben, now I have an excuse to cough up a 2c Tip.
</STRONG></P>
<P>
Cool. Thanks!
</P>
<P><STRONG>
The two places to look for "the rest of it" if you really want a bleeding
edge kernel are:
</STRONG></P>
<P><STRONG><dl>
<dt>For Linus' tree -
<dd> <A HREF="http://www.kernel.org/pub/linux/kernel/testing"
	>http://www.kernel.org/pub/linux/kernel/testing</A>
</dl></STRONG></P>
<P>
Nope; just 2.4.x stuff.
</P>
<P><STRONG><dl>
<dt>For Alan's tree -
<dd> <A HREF="http://www.kernel.org/pub/linux/kernel/people/alan"
	>http://www.kernel.org/pub/linux/kernel/people/alan</A>
</dl></STRONG></P>
<P><STRONG>
Alan keeps subdirectories in there which should help you figure things
out.  In the moment I type this, his 2.4.6 patch is at ac5 and his
2.2.20pre is at 7.
</STRONG></P>
<blockquote><em>
As of press time, 2.4.7 patch is at ac3 and 2.2.20pre is at 8. -- Heather
</em></blockquote>
<P><STRONG>
These are of course patches that you apply to the standard source
after you unpack the tarball.
</STRONG></P>
<blockquote>
<em>
For a last tidbit, the web page at <A HREF="http://www.kernel.org/"
	>http://www.kernel.org</A> keeps track
of the current Linus tree, listing both the released version number
and the latest file in the <TT>/testing</TT> area.
</em>
</blockquote>

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<P> <A NAME="tips/6"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Linux on Sun Sparc??</FONT></H3>
Thu, 26 Jul 2001 08:53:42 -0700 (PDT)
<BR>Heather Stern (<a href="mailto:linux-questions-only@ssc.com">The Answer Gang</a>)

<P>
Question From: Danie Robberts  &lt;DanieR from PQAfrica.co.za&gt;
</P>
<P><STRONG>
Is there a way to install this. I can see the Sparc64 architecture under
/usr/src/linux/arch
</STRONG></P>
<P><STRONG>
Booting from the slackware 8 cd does not work, and it seems as if
<A HREF="http://www.slackware.org/">Slackware</A>'s Web site is "unavailable"
</STRONG></P>
<P><STRONG>
Please, any pointers!
</STRONG></P>
<P><STRONG>
Cheers
Danie
</STRONG></P>
<P>
Sure.
</P>
<P>
The  <A HREF="http://www.lwn.net/">Linux Weekly News</A>  just wrote that Slackware is no longer supporting
their Sparc distro.  There's a sourceforge project to take over the code:
<A HREF="http://sourceforge.net/projects/splack"
	>http://sourceforge.net/projects/splack</A>
</P>
<P>
Entirely possible that some decent community interest would boost it nicely,
but if so, why'd Slackware have to let go of it... dunno...
</P>
<P>
Maybe you want to try another distro that builds for Sparc - RH's sparc build
isn't well regarded amongst a few non-Intel types I know locally... I think
in part because they get to Sparcs last.  But you've lots of choices anyway.
The search engines (keywords: sparc distribution) reveal that Mandrake and
<A HREF="http://www.suse.com/">SuSE</A> both have Sparc distros, Rock Linux (a distro that builds from sources
- <A HREF="http://www.rocklinux.org"
	>http://www.rocklinux.org</A>) builds successfully on it, and of course there's
my personal favorite, <A HREF="http://www.debian.org/">Debian</A>.
</P>
<P>
The Sparc-HOWTO adds <A HREF="http://www.caldera.com/">Caldera</A> OpenLinux and <A HREF="http://www.turbolinux.com/">TurboLinux</A> to the mix.  I know
that Caldera is really pushing to support the enterprise  but that points
to openlinux.org and appears to be an unhappy weblink - I only did a spot
check, but didn't see "Sparc" on Caldera's own pages.  One may safely
presume that someone who wants Caldera's style of enterprise level support
for Linux will be getting Sun maintenance contracts for their high end Sparcs,
right?
</P>
<P>
Anyways the reasons that Debian is my personal favorite in this regard are:
</p>
<ol>
<li>It's the only distro that I've tried on a Sparc
<li>It worked just as smoothly as on a PC
<li><tt>apt-get install</tt> &lt;package name here&gt;
</ol>
<P>
But you don't have to take my word for it 
<IMG SRC="../gx/dennis/smily.gif" ALT=":)" 
		height="24" width="20" align="middle"> There's a bunch of folks at
<A HREF="http://www.ultralinux.org"
	>http://www.ultralinux.org</A>
</P>
<P>
who pay attention to how well things work on ultrasparcs, and they've
helpfully gathered a bunch of pointers into the arcvhives and subscribe
methods for the lists maintained by the major vendors in this regard.  So
check out what people who really use Sparcs have been saying about 'em!
Using your model number as a search key may narrow things down, too.
</P>

<!-- end 6 -->
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<P> <A NAME="tips/7"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Routing Mail</FONT></H3>
Thu, 19 Jul 2001 08:50:47 -0700
<BR>Dan Wilder (<a href="mailto:linux-questions-only@ssc.com">The Answer Gang</a>)

<P>
Question From: Danie Robberts (DanieR from PQAfrica.co.za)
</P>
<P><STRONG>
Hi,
</STRONG></P>
<P><STRONG>
I am trying to set my environment up so that I can use Star Office on my
<A HREF="http://www.slackware.org/">Slackware</A> 8 Laptop, and send mail via our Exchange Servers.
The problem is that the IIS Department has only allowed my Suna Workstation
to Send mail to their List server. I think it is limited by IP @.
</STRONG></P>
<P><STRONG>
Is there a way to configure a type of mail routing agent, so that my sending
adress in S/O will be the IP@ of my Sun Workstation, and the receiving will
be the exchange server (At the moment I can only receive e-mail)
</STRONG></P>
<P><STRONG>
Here is the IP Setup:
</STRONG></P>

<pre><strong> List Server:	196.10.24.112
 Exchange 	196.10.24.33
 Laptop:		192.168.102.241
 Sun:		192.168.102.44
</strong></pre>

<P><STRONG>
Thanx
<br>
Danie
</STRONG></P>
<P>
Not directly, while your Sun workstation is online.  You'd have to give
your Linux workstation the Sun's IP number.  Two hosts with the same IP
on the same network is a recipe for trouble!
</P>
<P>
If you've full control of your Sun, you could arrange to use
it as your email relay host, for an indirect solution.
</P>
<P>
It looks like StarOffice can be configured to use two different
mail servers, one for outgoing, one for incoming.  Set the outgoing
server to the Sun, and the incoming to the exchange server.
Configure the MTA on the Sun (sendmail, I expect) to relay for
you, and you're all set.
</P>
<P>
To test the Sun,
</P>

<blockquote><pre>telnet sun 25
helo linux.hostname
mail from: &lt;you@your.domain&gt;
rcpt to: &lt;somebody@reasonable.domain&gt;
data
some data
.
quit
</pre></blockquote>
<P>
"linux.hostname" is the hostname of your linux system
"<A HREF="mailto:you@your.domain"
	>you@your.domain</A>" is your return email address
"<A HREF="mailto:somebody@reasonable.domain"
	>somebody@reasonable.domain</A>" is some reasonable recipient
</P>
<P>
If you don't get a refusal, and the email goes through, the
Sun is set up to relay.
</P>

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<P> <A NAME="tips/8"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Command to read CMOS from running Linux system</FONT></H3>
Wed, 20 Jun 2001 09:01:11 +0000
<BR>Andrew Higgs (<a href="mailto:linux-questions-only@ssc.com">The Answer Gang</a>)

<P>
Question From: Paul Kellogg (pkellogg from avaya.com)
</P>
<P><STRONG>
To "The Answer Gang":
</STRONG></P>
<P><STRONG><BLOCKQuote>
I am looking for a program I can run on my Linux machine that will
display the CMOS settings and CPU information.  I would like to avoid
rebooting to display the information.  Have you heard of a program that will
work for this?  And if so, do you know where I can get it?  If not, do you
have some suggestions for where to start if I wanted to write such a program?
I am working with a RedHat 6.2 system on a intel platform.
</BLOCKQuote></STRONG></P>
<P><STRONG>
Thanks - Paul.
</STRONG></P>
<P>
Hi Paul,
</P>
<P>
Try `<TT>cat /proc/cpuinfo`</TT> for information regarding the CPU. I am not to sure
about the CMOS info. It depends what you are looking for?
</P>
<P>
Look at the files in <TT>/proc</TT> and see if you can find what you are looking for.
</P>
<P>
I hope this will help in some small way.
</P>
<P>
Kind regards
</P>

<!-- end 8 -->
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<P> <A NAME="tips/9"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">linux ftp problem</FONT></H3>
Thu, 21 Jun 2001 12:18:42
<BR>Thomas Adam &lt;<A HREF="mailto:n6tadam@users.purbeck.dorset.sch.uk">The Weekend Mechanic</A>&gt; 

<P>
Question From: Brad Webster (webster_brad from hotmail.com)
</P>
<P><STRONG>
ok heres the deal, im having a heck of a time with the ftp client on my
linux server. im running red hat 6 and i can connect fine, but then it will
not accept the username  and password for any of the users. the worst part
is the same username and passwords will connect through telnet?
any suggestions would be very appriciated
</STRONG></P>
<P><STRONG>
bard webster
</STRONG></P>
<P>
Hello,
</P>
<P>
First off, I shall begin by saying, please in future send your e-mail in
plain-text format and NOT in HTML. Poor Heather will have a hell of a time
trying to extract the important information from the e-mail 
<IMG SRC="../gx/dennis/smily.gif" ALT=":-)" 
		height="24" width="20" align="middle">
</P>
<blockquote><em>
It's easier than quoted printable, but, yeah, it's a pain. -- Heather
</em>
</blockquote>
<P>
So, to your problem. There are a number of things that you can check.
Firstly, when using FTP, do you make use of the hidden files ".netrc", in
each of your users home directory? In that file, you can store the ftp
machine, and the username and password of the user. Typically, it would look
like the following:
</P>

<blockquote><pre>machine ftp.server.sch.uk   login   usernametom  password xxxxxxx
</pre></blockquote>
<P>
The reason why your users can log in via telnet, is that telnet uses
different protocols. I would also suggest using a program such as "ssh",
which is more secure than telnet, but I digress.
</P>
<P>
Regards,
</P>
<P>
Thomas Adam
</P>

<!-- end 9 -->
<!--     .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.     -->
<P> <A NAME="tips/10"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Self extracting shell script</FONT></H3>
Sat, 7 Jul 2001 22:26:22 -0400
<BR>Ben Okopnik (<a href="mailto:linux-questions-only@ssc.com">The Answer Gang</a>)
<P>
Question From: Albert J. Evans (evans.albert from mayo.edu)
</P>
<P><STRONG>
Hi,
</STRONG></P>
<P><STRONG>
I'm looking through some older Linux Gazzette articles and noticed
"fuzzybear" had put out a location to download his "self extracting w/make"
shell script. He was responding to your inquiry about this script. The URL
he listed is now defunct. Did you by chance get a copy of it, or know his
current URL?
</STRONG></P>
<P>
You know, I searched the past issues of LG... and I must admit that I
couldn't find my own article mentioning that. I'm pretty sure that the
URL I gave is the same as it is now - I don't rememberr changing it at
all - and I've just tested it (with Lynx.) It's still good. Anyway,
here it is -
</P>
<P>
<A HREF="http://www.geocities.com/ben-fuzzybear/sfx-0.9.4.tgz"
	>http://www.geocities.com/ben-fuzzybear/sfx-0.9.4.tgz</A>
</P>
<P>
The reason I haven't been particularly hyped about this thing is that,
the more time passes, the less I think of it as a good idea. Given that
one of the classes I teach for a living is Unix (Solaris) security, it's
actually my job to believe that it's a bad idea. 
<IMG SRC="../gx/dennis/smily.gif" ALT=":)" 
		height="24" width="20" align="middle"> Just like many other
things, it's perfectly fine as long as you trust the source of the data
- but things rapidly skid downhill as soon as that comes into question.
Sure, in the Wind*ws world, people blithely exchange "Setup.exe" files;
they also suffer from innumerable viruses, etc.
</P>
<P>
Think well before you use this tool. Obviously - and if it isn't
obvious, even downloading it might be a bad idea - never-ever-*ever* run
a self-extracting archive, or any executable that is not 100%
trustworthy, as root.
</P>
<blockquote><em>...at this point Ben drew a huge ASCII-art skull and crossbones...</em></blockquote>
<P>
You have been warned. 
<IMG SRC="../gx/dennis/smily.gif" ALT=":)" 
		height="24" width="20" align="middle">
</P>
<P>
Ben Okopnik
</P>

<!-- end 10 -->
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<P> <A NAME="tips/11"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Cannot Format Network Drive</FONT></H3>
Sat, 14 Jul 2001 12:49:30 -0400
<BR>Ben Okopnik (<a href="mailto:linux-questions-only@ssc.com">The Answer Gang</a>)

<P><STRONG>
I'm not quite sure if you can help me out with this situation.
Okay here's the lay down
I have 1 IDE Hardrive 35 gigs
About a month ago I added the program System Comander so I could put Windows
98, Windows 2000, and Linux on my system.
I did it successfully!
So now about a week ago I wanted everything off, cause I bought a serperate
PC for Linux.
This is how I wipe everything off of my drive.
I used a Debug to wipe everything off and used fdisk to try to get rid off
all of the partititions... but it still didn't get all of the partitions off
(looking in fdisk). How I got rid of all of them was doing the commands
</STRONG></P>

<pre><strong>lock c:
fdisk /mbr
</strong></pre>
<P><STRONG>
Than going back to fdisk and deleted the remaining partitions.
This did work... no longer is there any drives stated in fdisk.
So than I created 2 drive c: and d: both about 15 gigs or more
But now this is were I run into my problem....
After rebooting I tried to format those drives a it's giving the error
message CANNOT FORMAT A NETWORK DRIVE????
I know this is a lot more information than you prbably needed, but I thought
I'd better say everything so that you know the whole story...
Can you help me?
Do you know of anything I could try?
</STRONG></P>
<P>
Well, since you've removed Linux, your options are pretty thin.
It sounds like your 'fdisk' screwed up somewhere, or you have a
virus (I remember, a looong time ago, of some that did that.) One of
the easiest ways to handle it would be to download <A HREF="http://www.toms.net/rb/">Tom's rootboot</A>
&lt;<A HREF="http://www.toms.net/rb/&gt"
	>http://www.toms.net/rb/&gt</A>;, run it, and use the Linux fdisk that comes
with it (you should read the 'fdisk' man page unless you're very
familiar with it.) It can rewrite your partitions and assign the correct
types to them; after that, you should be able to boot to DOS and do
whatever you need.
</P>
<P>
Ben Okopnik
</P>

<!-- end 11 -->
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<P> <A NAME="tips/13"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Wu-FTP and Linux Newbie</FONT></H3>
Wed, 11 Jul 2001 18:40:57 +0200 (MET DST)
<BR>Karl-Heinz Herrmann (<a href="mailto:linux-questions-only@ssc.com">The Answer Gang</a>)

<P>
Question From: seboulva (seboulva from gmx.de)
</P>
<P><strong>
Sorry about this Simple Question, but I am a Linux Newbie and I want, no  I
must Update our Wu- FTP Server.It Comes with <A HREF="http://www.redhat.com/">Red Hat</A> 6.3
</strong></P>
<P><STRONG>
I Downloaded the 3 *.patch Files . And want to Apply it with the Patch
Command.
</STRONG></P>
<P>
Do you have the source code for wu-ftp and did you compile it yourself last
time? patch files are usually for source code, and they will change a
specific version to a specific other version. Are you sure that the patch
files math your source code version?
If it's RedHats patch files for their 6.3 distribution that should match.
But most probably it matches only the source code from their 6.3 CD's.
</P>
<P>
If all this matches, you should be able to compile the basic wu-tfp as it
comes with 6.3. Then you can try to patch the source and recompile.
</P>
<P>
Depending on the patch files (especially with which path they are generated)
you would do something like:
</P>

<blockquote><pre>cd wu-ftp-source
patch -p 1 &lt; ./path/to/patchfile
</pre></blockquote>
<P>
the -p x optioon strips off x directory levels from the path in the patch
file. If you look in the  ascii patch-files you will see file names with
path -- they have to match where your source is.
</P>
<P>
'patch --help' says among other very usful thing:
</P>

<blockquote><pre>  --dry-run  Do not actually change any files; just print what would happen.
</pre></blockquote>
<P>
so this is the option for testing until it looks as if it will apply
cleanly. Then remove the dry-run and do it for real.
</P>
<P>
recompile wu-ftp and then install it in the system. You will have to restart
it of course.
</P>
<P>
K.-H.
</P>

<!-- end 13 -->
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<P> <A NAME="tips/14"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Root Password</FONT></H3>
Mon, 02 Jul 2001 14:02:18 -0400
<BR>Thomas Adam &lt;<A HREF="mailto:n6tadam@users.purbeck.dorset.sch.uk">The Weekend Mechanic</A>&gt; 

<P>
Question From: Adam Wilhite (a.m.wilhite from larc.nasa.gov)
</P>
<P><STRONG>
Somehow the root password was lost or doesn't work anymore for one of
the computers I administer.  I went through your steps to reboot with
init=/bin/sh...  My problem is when I try to mount <TT>/usr</TT>. It says it
can't find <TT>/usr.</TT>  I would really appreciate your help.
</STRONG></P>
<P><STRONG>
thanks,
<br>adam wilhite
</STRONG></P>
<P>
Hi,
</P>
<P>
Your error message about not being able to find <TT>/usr</TT>, suggests to me that
"<TT>/usr</TT>" is not your mount point. Take a look in the file "<TT>/etc/fstab</TT>", which
is the filesystem table.
</P>
<P>
Locate the entry which points to "<TT>/usr</TT>". Your mount points are usually in
the second field, i.e. after all the "<TT>/dev/hda1</TT>" entries.
</P>
<P>
When you have found it, type in the correct value, using:
</P>
<P><CODE>
mount /path/to/mountpoint
</CODE></P>
<P>
Failing that, try issuing the command:
</P>
<P><CODE>
mount -a
</CODE></P>
<P>
that will tell your computer, to (try and) mount all the entries within the
file "<TT>/etc/fstab</TT>". You can then check what has been mounted, by typing in
the following:
</P>
<P><CODE>
mount
</CODE></P>
<P>
HTH,
</P>
<P>
Thomas Adam
</P>

<!-- end 14 -->
<!--     .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.     -->
<P> <A NAME="tips/15"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">RH7.1 switch to KDE login as default</FONT></H3>
Fri, 6 Jul 2001 11:09:13 -0400
<BR>Faber Fedor (<a href="mailto:linux-questions-only@ssc.com">The Answer Gang</a>)

<P>
Questions From: Larry Sanders (lsanders from hsa-env.com) and Jim (<em>anonymous</em>)
</P>
<P><STRONG>
Having completed the installation of <A HREF="http://www.redhat.com/">Red Hat</A> 7.1 with both
<A HREF="http://www.gnome.org/">GNOME</A> and <A HREF="http://www.kde.org/">KDE</A>, the default graphical login is GNOME.
How is this changed to the KDE default login for the system?
-- Larry
</STRONG></P>
<P><STRONG><FONT COLOR="#000066"><EM>
I love and use both the KDE and Gnome desktops. I have a strong
aesthetic preference, though, for the KDE login manager.
</EM></FONT></STRONG></P>
<P><STRONG><FONT COLOR="#000066"><EM>
My RedHat 7.1 install has resisted all efforts to switch it from its
default Gnome login manager to the KDE one. This isn't a big deal but
where is this managed and how do I make the change?
-- Best Regards, Jim
</EM></FONT></STRONG></P>
<P>
Try running the program "switchdesk".  It might be on the GNOME menu,
but you can run it from a command-line quicker.  It will let you switch
default desktops and even different desktops for different displays
(although that tends to be a bit problematic).
</P>
<P>--
Regards,
<br>
Faber Fedor
</P>

<!-- end 15 -->
<!--     .~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.~~.     -->
<P> <A NAME="tips/16"><HR WIDTH="75%" ALIGN="center"></A> <P>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">3d linux</FONT></H3>
Mon, 16 Jul 2001 22:04:19 +0200
<BR>Zdenko Podobny (<a href="mailto:linux-questions-only@ssc.com">zdpo from mailbox.sk</a>)


<!-- sig -->

<P>
Hello!
</P>
<P>
This week I found some interesting programs that can help (a little bit) to
Philippe CABAL.
</P>
<dl>
<dt>K-3D
<dd><A HREF="http://freshmeat.net/redir/k-3d/4976/url_tgz/k3d-0.1.29.0-src.tar.gz"
	>http://freshmeat.net/redir/k-3d/4976/url_tgz/k3d-0.1.29.0-src.tar.gz</A>
</dl>
<p>It is frontend(Opensource, GPL) to render engines that are available to
linux and win:</p>
<dl>
<dt>BMRT, 
<dt>RDC 
<dd>(<A HREF="ftp://ftp.dotcsw.com/rdc32lnx.tar.gz"
	>ftp://ftp.dotcsw.com/rdc32lnx.tar.gz</A> -&gt;demo)
<dt>and 3Delight 
<dd>(<A HREF="http://www.3delight.com"
	>http://www.3delight.com</A> - I didn't try it)
</dl>
<P>
BTW: K-3D is one of the best applications I have seen on linux. Also no
other application need so much time and memory resources for
compiling like K-3D
</P>
<P>
<A HREF="http://www.dotcsw.com"
	>http://www.dotcsw.com</A> have perfect page with links. There is lof of
rendering staff (also many that are just expected)
</P>
<P>
I hope this help.
</P>
<P>
Zdeno
</P>

<!-- end 16 -->
<P> <hr> </p>
<!-- *** BEGIN copyright *** -->
<H5 align="center">This page edited and maintained by the Editors
	of <I>Linux Gazette</I> 
<a href="http://www.linuxgazette.com/copying.html"
	>Copyright &copy;</a> 2001
<BR>Published in issue 69 of <I>Linux Gazette</I> August 2001</H5>
<H6 ALIGN="center">HTML script maintained by
	<A HREF="mailto:star@starshine.org">Heather Stern</a> of
	Starshine Technical Services,
	<A HREF="http://www.starshine.org/">http://www.starshine.org/</A> 
</H6>
<!-- *** END copyright *** -->

<H4 ALIGN="center">
"Linux Gazette...<I>making Linux just a little more fun!</I>"
</H4>

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

<center>
<H1><font color="maroon">HelpDex</font></H1>
<H4>By <a href="mailto:shane_collinge@yahoo.com">Shane Collinge</a></H4>
</center>
<P> <HR> <P>  

<!-- END header -->




<IMG ALT="bb.jpg" SRC="misc/collinge/bb.jpg" 
	WIDTH="750" HEIGHT="303">
<BR CLEAR="all">

<IMG ALT="cleaners.jpg" SRC="misc/collinge/cleaners.jpg" 
	WIDTH="750" HEIGHT="303">
<BR CLEAR="all">

<IMG ALT="degaussed.jpg" SRC="misc/collinge/degaussed.jpg" 
	WIDTH="750" HEIGHT="303">
<BR CLEAR="all">

<IMG ALT="escape.jpg" SRC="misc/collinge/escape.jpg" 
	WIDTH="750" HEIGHT="303">
<BR CLEAR="all">

<IMG ALT="gameboy.jpg" SRC="misc/collinge/gameboy.jpg" 
	WIDTH="750" HEIGHT="303">
<BR CLEAR="all">

<P> Here's a peek at Shane's sketchbook:

<BR>
<IMG ALT="Batman.jpg" SRC="misc/collinge/Batman.jpg" 
	WIDTH="750" HEIGHT="332">
<BR CLEAR="all">


<P> More HelpDex cartoons are at
<A HREF="http://www.shanecollinge.com/Linux/">http://www.shanecollinge.com/Linux</A>.  This month, Shane has also been busy doing some
<A HREF="http://www.shanecollinge.com/Illustrations/">illustrations</A> 
(non-Linux).


<!-- *** BEGIN bio *** -->
<SPACER TYPE="vertical" SIZE="30">
<P> 
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Shane Collinge</H4>
<EM>Part computer programmer, part cartoonist, part Mars Bar. At night, he runs
around in a pair of colorful tights fighting criminals. During the day... well,
he just runs around.  He eats when he's hungry and sleeps when he's sleepy.</EM>

<!-- *** END bio *** -->

<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P --> 
<H5 ALIGN=center>

Copyright &copy; 2001, Shane Collinge.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR> 
Published in Issue 69 of <i>Linux Gazette</i>, August 2001</H5>
<!-- *** END copyright *** -->


<H4 ALIGN="center">
"Linux Gazette...<I>making Linux just a little more fun!</I>"
</H4>

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

<center>
<H1><font color="maroon">Make Your Virtual Console Log In Automatically</font></H1>
<H4>By <a href="mailto:bryanh@giraffe-data.com">Bryan Henderson</a></H4>
</center>
<P> <HR> <P>  

<!-- END header -->




<p>When you boot Linux, do you get a "login:" prompt on a bunch of
virtual consoles and have to type in your username and password on
each of them?  Even though you're the only one who uses the system?
Well, stop it.  You can make these consoles come up all logged on and
at a command prompt at every boot.

<p>In case you're thinking that password prompt is necessary for
security, think again.  Chances are that if someone has access to your
console keyboard, he also has access to your floppy disk drive and
could easily insert his own system disk in there and be logged in as
you in three minutes anyway.  That password prompt is about as useful
as an umbrella for fish.

<h2>Introduction</h2>

<p>The method I'm going to describe for getting your virtual consoles
logged in automatically consists of installing some software and
changing a few lines in <strong>/etc/inittab</strong>.  Before I do
that, I'll take you on a mind-expanding journey through the land of
getties and logins to see just how a Unix user gets logged in.

<p>First, I must clarify that I'm talking about virtual consoles --
those are text consoles that you ordinarily switch between by pressing
ALT-F2 or CTL-ALT-F2 and such.  Shells that you see in windows on a
graphical desktop are something else entirely.  You can make those
windows come up automatically at boot time too, but the process is
quite a bit different and not covered by this article.

<p>Also, consider serial terminals:  The same technique discussed in
this article for virtual consoles works for serial terminals, but may
need some tweaking because the terminal may need some things such as
baud rate and parity set.

<h2>How Logging In Works</h2>

<h3>Historical Background</h3>

<p>In the traditional Unix system of old, the computer was in a
locked room and users accessed the system via terminals in another
room.  The terminals were connected to serial ports.  When the system
first came up, it printed (we're back before CRT terminals -- they
really did print) some identification information and then a "login:"
prompt.  Whoever wanted to use the computer would walk up to one of
these terminals and type in his username, then his password, and then
he would get a shell prompt and be "logged in."

<p>Today, you see the same thing on Linux virtual consoles, though it
doesn't make as much sense if you don't think about the history.

<h3>Getty</h3>

<p>Let's go through the Linux boot process now and see how that login
prompt gets up there.

<p>When you first boot Linux, the kernel creates the
<strong>init</strong> process.  It is the first and last process to
exist in any Linux system.  All other processes in a Linux system are
created either by <strong>init</strong> or by a descendant of
<strong>init</strong>.

<p>The <strong>init</strong> process normally runs a program called
Sysvinit or something like it.  It's worth pointing out that you can
really run any program you like as <strong>init</strong>, naming the
executable in Linux boot parameters.  But the default is the
executable <strong>/sbin/init</strong>, which is usually Sysvinit.
Sysvinit takes its instructions from the file
</strong>/etc/inittab</strong>.

<p> To see how <strong>init</strong> works, do a <kbd>man init</kbd> and
<kbd>man inittab</kbd>.

<p>If you look in <strong>/etc/inittab</strong>, you will see the
instructions that tell it to start a bunch of processes running a
getty program, one process for each virtual console.  Here is an
example of a line from <strong>/etc/inittab</strong> that tells
<strong>init</strong> to start a process running a getty on the
virtual console <strong>/dev/tty5</strong>:

<xmp>
   c5:235:respawn:/sbin/agetty 38400 tty5 
</xmp>

<p> In this case, the particular getty program is
<strong>/sbin/agetty</strong>.  On your system, you may be using
<strong>/sbin/mingetty</strong> or any of a bunch of other programs.
(Whatever the program, it's a good bet it has "getty" in its name.  We
call these getties because the very first one was simply called
"getty," derived from "get teletype".)

<p>Getty opens the specified terminal as the standard input, standard
output, and standard error files for its process.  It also assigns
that terminal as the process' "controlling terminal" and sets the
ownership and permissions on the terminal device to something safe
(resetting whatever may have been set by the user of a previous login
session).

<p>So now you can see how the login prompt gets up on virtual console
<strong>/dev/tty5</strong>.  The kernel creates the
<strong>init</strong> process, running Sysvinit.  Sysvinit, as
instructed by its <strong>/etc/inittab</strong> file, starts another
process running a getty program, with parameters identifying
<strong>/dev/tty5</strong>.  The getty program prints "login:" on
<strong>/dev/tty5</strong> and waits for someone to type something.

<h3>Login</h3>

<p> After you respond to getty's login prompt, getty execs the program
<strong>login</strong>.  (Actually, you can usually tell getty to execute
any program of your choice, but <strong>/bin/login</strong> is normal);
i.e. <strong>getty</strong> replaces itself with <strong>login</strong>.  It's
still the same process, though.

<p> Bear in mind that this process was created by <strong>init</strong>,
which is owned by the superuser.  So this process, which is now
running login, is also owned by the superuser.

<p> The first thing <strong>login</strong> does is ask for your password.
When you type it in, <strong>login</strong> determines if it's right or
not.  Assuming it is, login then proceeds to do the following things:

<ul>
<li>
Set the owning user id of the process to you.
<li>
Set the owning group id of the process to your group.
<li>
Put a record in the user accounting database (the "utmp" file)
showing that you are logged in.  This database is technically
unnecessary today, but it is still used by old programs such as
<strong>who</strong> to tell who is logged on and at what terminal.
<li>
Set the process' supplemental groups to all the groups to which
you belong.
<li>
Set the process' current working directory to your home directory.
<li>
Make you the owner of the terminal device and set its permissions
appropriately.
</ul>

<p> The next thing <strong>login</strong> does is exec your shell program
(which can really be any program, but is normally a command shell,
e.g. <strong>/bin/bash</strong>).  I.e.  it replaces itself with the shell
program.

<p> Login looks up your username in the file <strong>/etc/passwd</strong>
to find all the information it needs, such as your password, uid, and
shell program.

<h3>The Shell</h3>

<p> The shell proceeds to run the system shell profile
(<strong>/etc/profile</strong>) and your personal profile (typically the
file <strong>.profile</strong> in your home directory), and ultimately
display a command prompt (<code>$</code> or <code>%</code>) on the terminal.  
This is the point at which
you consider yourself logged in, and our journey is complete.

<h2>Automating Login</h2>

<p>Ok, that was fun, but our purpose in this article is to explore a
new kind of login -- an automated one.

<p>Our goal is to do all those things that <strong>init</strong>,
<strong>getty</strong>, <strong>login</strong>, and the shell do except
<em>without the username and password prompt</em>.

<p> There are a bunch of ways to do that, but I wrote the program
<strong>qlogin</strong> to do it all very simply.
<strong>qlogin</strong> performs the functions of
<strong>getty</strong> and <strong>login</strong>.  It gets called by
<strong>init</strong>, like getty, and its last act is to call the
shell program, like <strong>login</strong>.

<p> So to set this up, all you have to do is replace the
<strong>/etc/inittab</strong> line shown above with one something like
this:

<xmp>
   c4:235:respawn:/sbin/qlogin /dev/tty5 bryanh 
</xmp>

This logs in username <strong>bryanh</strong> to virtual console
<strong>/dev/tty5</strong> at boot time instead of going through the
username and password prompt business.

<p>Note that the "respawn" in the line above means that when the
process ends, <strong>init</strong> will create a new one to take its
place.  In the traditional Unix system, that means when you log out of
your shell, which causes the process to end, a new getty runs and the
terminal gets a login prompt for the next user.  In the
<strong>qlogin</strong> case, it means when you log out of your shell,
a new one comes up immediately to take its place.  So if you want to
reset a bunch of stuff in your login session, typing <kbd>logout</kbd>
is a good way to do it.

<h2>Starting Slowly</h2>

<p>You probably shouldn't install <strong>qlogin</strong> and then
just dive right into changing all your getty's to qlogin's in
<strong>/etc/inittab</strong> and reboot and see if it works.  That
would be pretty optimistic.

<h3>Diversity Is Good</h3>

<p>First of all, I recommend that you not convert <em>all</em> your
virtual consoles to <strong>qlogin</strong> ever.  Use the tried and
true getty/login system on at least one virtual console so that if you
mess up something with <strong>qlogin</strong>, you can get into
another virtual console and fix it.  And if you mess up something with
<strong>getty</strong> or <strong>login</strong>, you can get into
another virtual console via <strong>qlogin</strong> and fix that!

<h3>Run It From A Shell</h3>

<p>Before you go editing <strong>/etc/inittab</strong> and messing
around with the <strong>init</strong> task, you should convince
yourself you know what you're doing by running <strong>qlogin</strong>
from a shell.  Watch <strong>qlogin</strong> work with your own eyes.
The problem with <strong>init</strong>, besides the fact that it's a
very important process you don't want to break, is that it doesn't
have a standard error file -- no way to give you error messages to
tell you why it can't do what you thought you told it to do.

<p>Usually, the indication from <strong>init</strong> that something is
wrong is "id X spawning too fast.  Disabled for 5 minutes."  What that
means is that the program (e.g. <strong>qlogin</strong>) that you told
<strong>init</strong> to run runs into trouble and terminates immediately.
Because it's a "respawn" entry, <strong>init</strong> simply generates a
new process running the same program.  And these processes start and
crash repeatedly.  <strong>init</strong> notices this and suspends the
"respawn" procedure for 5 minutes in hopes that someone fixes the
problem.  But why is the program immediately crashing?  Nobody knows
except that program, and it's not telling.

<p>So just invoke <strong>qlogin</strong> from a shell prompt, with
the same arguments with which you would have <strong>init</strong>
invoke it.  Now <strong>qlogin</strong> will issue error messages if
it crashes.

<p>Of course, the shell from which you invoke <strong>qlogin</strong>
had better be a superuser shell.  Otherwise, I can tell you right now
what your error message will be.

<h4>One Difference - Controlling Terminal</h4>

<p>One tricky aspect of running <strong>qlogin</strong> from a shell is
the matter of the controlling terminal.  The login process you
generate with <strong>qlogin</strong> will use the terminal you specify as
its input and output terminal, but its controlling terminal will be
the terminal where you typed "<strong>qlogin</strong>."

<p>The reason for the difference is this: If you're a Linux process,
when you open a terminal for input and you don't already have a
controlling terminal, that terminal becomes your controlling terminal.
But if you already have a controlling terminal, you just keep it.
<strong>init</strong> does not have a controlling terminal, so neither
does the <strong>qlogin</strong> child process it creates.  But login
shells have controlling terminals, and therefore the child processes
you create by typing commands (such as <strong>qlogin</strong>) at
shell prompts do too.

<p>Where you will see the difference is when you type Control-C:  It
won't do anything.  Control-C typed on a standard input device has no
effect other than to include a Control-C character in the input
stream.  But Control-C on a controlling terminal causes the foreground
processes associated with that terminal to get a SIGINT signal, which
has the familiar effect of terminating the program.

<p>All I'm saying is that if you log yourself on to
<strong>/dev/tty5</strong> by typing <kbd>qlogin /dev/tty5 ...</kbd> on
<strong>/dev/tty1</strong>, then Control-C on <strong>/dev/tty5</strong> will
have no effect.  Put the same <kbd>qlogin /dev/tty5 ... </kbd> command
in <strong>/etc/inittab</strong>, and Control-C on <strong>/dev/tty5</strong>
will work fine.

<p> Note: to be pedantic, I must admit that in saying Control-C, I am
assuming that the terminal's TTY properties are set such that
Control-C is the "interrupt character."  You could use
<strong>stty</strong> to make the interrupt character something else or
not have one at all.

<h2>About Qlogin</h2>

<p> <Strong>qlogin</Strong> isn't on your system, so you'll have to
install it.  Get it from <a
href=ftp://ibiblio.org/pub/Linux/system/misc>ibiblio.org</a> and
follow the simple installation instructions.  As you will find, a
prerequisite is the Perl extension called <strong>User::Utmp</strong>,
which probably also is not on your system, so you'll have to follow
the instructions to get and install that too.

<p><Strong>qlogin</Strong> is written in Perl and is quite simple.  So
you can see for yourself the steps involved in logging in a user.  And
you can modify it to suit your particular needs.

<p>One of the nice things about <Strong>qlogin</Strong> is that it's so
basic that it doesn't even rely on configuration files.  You can tell
it everything it needs to know to log you in just with command line
parameters.  You can override your <strong>/etc/passwd</strong> file or
log in a user that isn't even in <strong>/etc/passwd</strong>.  You're in
control.

<p>
Let's look at <strong>qlogin</strong>'s options:
<dl>
<dt>--command
<dd>the "command" (a kind of sloppy way to say a program plus
its arguments) to run after <strong>qlogin</strong> exits.  <strong>/bin/bash</strong>
is typical.
<dt>--arg0
<dd>the Argument Zero value for the program that runs after
<strong>qlogin</strong> exits, which is what shows up in a <strong>ps</strong> display.
<dt>--uid
<dd>the numeric user id for the process.
<dt>--gid
<dd>the numeric group id for the process.
<dt>--homedir
<dd>the home directory and initial current working directory
for the process.
<dt>--utmp/--noutmp
<dd>determines whether <strong>qlogin</strong> logs the session in the user
accounting database (utmp file).
</dl>

<p> And <strong>qlogin</strong> arguments specify the terminal device to
use for the process.

<p> All the details of using <strong>qlogin</strong> are in the
documentation that comes with it.

<h2>Other Things You Can Do With Qlogin</h2>

<p> So now you know how to make logged in shells come up automatically
on the various virtual consoles.  But with a simple change to the
procedure, you can make other programs run automatically on certain
virtual consoles or on serial terminals.  Imagine a virtual console
that runs the <strong>top</strong> system monitor program all the time.
Just say

<xmp>
  qlogin /dev/tty5 root --command=/bin/top --noutmp
</xmp>

<p> Maybe your system is a point of sale system for a store.  The
terminals are serial terminals at the cashier stations.  Cashiers
don't want to log in to Linux and don't want to see a shell.  If the
POS program is <strong>/usr/local/bin/pos</strong>, you could do this:

<xmp>
  qlogin /dev/ttyS1 cashier --uid=500 --gid=500 --command=/usr/local/bin/pos
      --arg0=POS --homedir=/
</xmp>

In this case, the <strong>pos</strong> program probably needs to do some
initialization of the serial port, such as setting its baud rate.  In
the traditional Unix login model, <strong>getty</strong> does that before
it puts up the login prompt.

<h1>Foreground Processes</H1>

<blockquote><em>[Your Editor asked Bryan, "I thought the system didn't have a
concept of a foreground process; that's a fiction of the shell."  Here's his
response.  --Iron]</em></blockquote>

<P>  I used to think that too; probably because of something I read in Bash
documentation.  However, the Linux kernel defines a "foreground
process group."  Every controlling terminal has a foreground process
group.  By default, it is the process group of the process that
originally opened the terminal.  But a process can set the foreground
process group to any process group in its session with an ioctl.

<P> I took a slight liberty in the article in referring to "foreground
processes," which I think can easily be interpreted as "processes in
the foreground process group."

<P> I believe the only significance of the foreground process group (the
kernel entity) is that the processes in that process group get the
control-C and hangup signals.

<P> Bash's job control uses that ioctl to make whatever your "foreground
job" is the foreground process group for your terminal.  That's why
when you put something in the background, like "grep abc * &",
control-C does not kill it.  If you want to kill it, you have to "fg",
causing Bash to ioctl it to the foreground, then Control-C.

<P> Many years ago, before the Web when terminals mattered a lot more, I
spent many hours combing through kernel code and experimenting to
figure out process groups, sessions, controlling terminals, job
control, SIGINT, SIGHUP, and the like.  I could write a long article
on it, but I think it's really arcane information.

<blockquote><em>[Readers: if you want to take him up on his offer for
such "arcane information", ask in the Mailbag.  Also remember that the
Mailbag is where you can ask for articles on any other topic. --Iron]
</em></blockquote>


<!-- *** BEGIN bio *** -->
<SPACER TYPE="vertical" SIZE="30">
<P> 
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Bryan Henderson</H4>
<EM>Bryan Henderson is an operating systems programmer from way back,
working mostly on large scale computing systems.  Bryan's love of
computers began with a 110 baud connection to a local college for a
high school class, but Bryan had little interest in home computers
until Linux came out.</EM>

<!-- *** END bio *** -->

<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P --> 
<H5 ALIGN=center>

Copyright &copy; 2001, Bryan Henderson.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR> 
Published in Issue 69 of <i>Linux Gazette</i>, August 2001</H5>
<!-- *** END copyright *** -->


<H4 ALIGN="center">
"Linux Gazette...<I>making Linux just a little more fun!</I>"
</H4>

<P> <HR> <P> 
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<center>
<H1><font color="maroon">Creating a Kernel Driver for the PC Speaker</font></H1>
<H4>By <a href="mailto:berryplumis@yahoo.com">Cherry George Mathew</a></H4>
<H5>Originally published at 
<A HREF="http://linux.com/">Linux.com</A>  
(<A HREF="http://Linux.com/newsitem.phtml?aid=12197&sid=93&page=1">article URL</A>)<BR>
Reprinted with permission from Linux.com and with revisions by the author</H5>
</center>
<P> <HR> <P>  

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<p>Sometimes I wonder how easy it is to re-invent the wheel, and then to
prattle about how hard it was to get the thing moving. But then again this
article is for those die-hards that sympathise with me, for those folk that
reckon that the joy of doing something by oneself is more important than being
the pioneer, the first soul on earth to step on the moon......</p>

 

<p><strong>I decided to make the PC speaker spew rock music.</strong> 
(The speaker is that invisible little thing under the PC
hood that beeps under your skin when you get naughty.)  I
wanted it to play real music. I couldn't bother to write all the code from
scratch, to decode mp3, etc etc. So I got a little lazy and decided to play
games with the most documented, most sophisticated Operating System Kernel,
ever - Linux. ;)  </p>

<p>How do you go about it, when you are new to a city and want to get from
point 'a' to 'b' with confidence? I'd take a deep breath and start walking
downtown. I'd start gleaning information and discovering places. Foolhardy?
Just try it in the city of the Linux kernel. It's a maze of code, a dizzy
labyrinth of cross-linked directories and makefiles. When I started off, I knew
that this was going to be a long project. But I had the 'staff' of DOS and the
'rod' of <i>Peter Norton's guide to the IBM PC and Compatibles</i> with me to
lend me courage. So off I strode with my chin in the air, and ready to take on
the worst d(a)emons.</p>

<p>The PC-speaker driver patches that are available for download from, 
<a href="ftp://ftp.uk.linux.org/pub/people/dwmw2/pcsp/">ftp://ftp.uk.linux.org/pub/people/dwmw2/pcsp/ </a>   (Authored by Michael Beck, maintained by David Woodhouse see 
<a href="http://linux-patches.rock-projects.com/v2.2-d/pcsp.html">http://linux-patches.rock-projects.com/v2.2-d/pcsp.html</a> )  I understand, require to have the kernel recompiled if they are to work. When I started off, I was ready to play foul, and get quick results. Besides it's all a game, is it not ? ;-) That's why you'll find inline assembly in the code.Anyways, here is how it works..........</p>

<h2>The PC speaker: background</h2>

<p>The internal speaker is tied to the buffered output of the 8254 timer chip
on all PCs. The output of the 8254 timer is further latched through the
integrated system peripheral chip, through port 61h. A little chart should
help, I think. Here goes:</p>

<p>
<img src="misc/mathew/speaker_illustration1.png" WIDTH="396" HEIGHT="82" 
BORDER="3">
</p>

<h2>PIC stands for programmable interrupt controller</h2>

<p>The base clock frequency of the 8254 is 1193180Hz which is 1/4 the standard
NTSC frequency, incidentally. The counters have the values of the divisors,
which, roughly speaking, are used to divide the base frequency. Thus the
output of channel 0 will be at a frequency of 1193180Hz if counter0=1,
596590Hz if counter0=2 and so on. Therefore counter0=0 =&gt; a frequency of
approximately 18.2 Hz, which is precisely the frequency at which the PIC is
made to interrupt the processor. In DOS, the PIC is programmed to call the
Interrupt Service Routine (ISR), at vector 8.</p>

<p>Effectively this means that the value of counter0 will determine the
frequency of the timer ISR (Vector 8 in DOS) is called. Changing counter 0
changes the rate at which the timer ISR is called. Therefore if the same
person wrote both the code for the ISR, and that for programming counter 0 of
the 8254 timer chip, then he could get his ISR called at a predetermined rate
as required.</p>

<p>All this is leading to another aside.</p>

<p></p>

<h2>Aside: digital audio</h2>

<p>When you hear sound, you know something near you is vibrating. If that
something is a speaker cone, you know immediately that there is an electrical
signal driving it. So we could always grab the signal generator by the scruff,
if we want to snuff out the noise. If we want audio, we need a vibrating, or
alternating, voltage. And we know that digital implies numbers, 1s and 0s. How
do we put all of this stuff together and create digital audio?</p>

<p>Lets imagine that we want a continuous hum to wake us out of slumber in the
morning. Bless the man who tries to sell this gadget to me! We need a
continuous sine wave. Something like:</p>

<p>
<img src="misc/mathew/speaker_illustration2.png" 
WIDTH="313" HEIGHT="118">
</p>

<p>The numbers represent how loud the noise gets at every instant. You're
involuntarily doing DSP here. DSP is a year two pain-in-the-neck paper for
most Electrical Engineering undergraduates. (I'm one of them. Accept my hearty
condolences.) So I'd better mention that you're actually looking at samples.
These values are all you need to recreate the wave we need. Do that
continuously, and you have a continuous wave. So if we ran through the numbers
starting at 1 through 7 through 0 through -1 through -7 through -1 to 0, all
in a second, we'd get a very approximate sine wave at 1Hz. (Remember, Hertz is
cycles per second.) Got the mechanics of the thing? Want a sine wave with a
smoother curve? Just increase the number of samples you take per second. Here
we've done 14. How about if it were 44000? That's the rate a CD player spews
the numbers out to its DAC. DAC stands for Digital to Analog Converter, it's
the little gadget that converts the 1s and 0s that make up the binary numbers
that we are talking about into real analog time-varying voltage. Our little
coding technique is called pulse code modulation. There are different ways to
code the pulses, so we have PCM, ADPCM etc. The waveform above could be termed
"4bit, signed mono PCM at 14Hz" sampling rate.</p>

<h2>1 Bit DAC</h2>

<p>So you ask me, where does all this come in when we're talking about the PC
speaker? How about a custom timer ISR to vibrate the speaker cone at a
pre-requisite frequency, so that all the ISR programmer has to do is to make
the PC speaker cone move to the required amplitude (distance from the zero
line) according to the sample value he gets from digital data, from a CDROM,
for example. This means that we can set up a timer ISR for 44000Hz, and that
is CD quality music staring at us! Perfect logic if you have a DAC to convert
every sample into the corresponding analog voltage. In fact, the parallel port
DAC driver does just that. Just rig a R - 2R ladder network of resistors and
tie a capacitor across the output, feed it to any amplifier, even a microphone
input will do, and voila, you have digital music!</p>

<p>Alas, things are not all that simple with the PC speaker. All because the
PC speaker is not at all tied to a DAC, but of all things, to a timer chip.
Take look at the waveform output of a timer chip for, say, a sine wave:</p>

<p>
<img src="misc/mathew/speaker_illustration3.jpg" WIDTH="370" HEIGHT="56">
</p>

<p>We have two discrete values to play around with: One +5V, the other 0V and
nothing in between. How do we get the Analog waveform? Oh man, why hast thou
asked the impossible? Ask the designers at IBM who designed the first XT
motherboards!</p>

<p>But we do have a very fragile, subtle solution. The techie terms are 1bit
DAC, Chopping, and so on and so forth.</p>

<p>It's rather simple and easy to implement, and somewhere down the line, it
was bound to happen. I doubt that the old XT bugger at IBM ever dreamt of 1.5
GHz Pentiums when he fixed his 8086 on the motherboard for the first time.</p>

<p>The idea is to drive the PC speaker cone in bursts, when we can't quite
push it up to the mark smoothly. Mind you, at 22Khz the cone is a mighty lazy
bloke, it reluctantly moves up to the mark. Halfway through, take a rest so
that if it's overdone and the cone has overshot, it gets time to come back
down. Something like anti-lock brakes in automobiles. When you press the brake
pedal half way down, the mechanism starts alternately pushing the brakes on
and off. When you're standing on the pedal, the brake shoes are not quite
stuck to the wheel drum, they're hammering at a furious pace. So you don't get
a locked wheel. Similarly the more frequently you hammer the speaker cone with
a +5V pulse, the farther it moves from the centerline. Bingo! Vary the
frequency of pulsing according to the required amplitude. I named the DOS
version fm.com just to remind myself that the idea was indeed ingenuous.</p>

<p>Now go back to the first figure and look at counter 2 of the 8254. Where does it lead to ? To the PC speaker, of course. Now all we have to do to get REAL sound, is to dump a scaled (remember 1 < countervalue < 65535) that is proportional to sample value (value => amplitude in PCM). We do this from within our hack timer ISR. Go on and take a look at the myhandler() function in myaudio.h</p>

<FONT COLOR="purple">
<h2> Quiz Time!!!!!</h2>

<DIV><b><i>&nbsp;&nbsp;smpl1&nbsp;&nbsp;&nbsp;&nbsp;smpl2&nbsp;&nbsp;&nbsp;&nbsp;smpl3</i></b></DIV>
<DIV>_______&nbsp;&nbsp;&nbsp;___&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;_</DIV>

<DIV>|&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;|&nbsp;&nbsp;|&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;|&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;|&nbsp;&nbsp;&nbsp;|</DIV>

<DIV>|&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;|&nbsp;&nbsp;|&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;|&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;|&nbsp;&nbsp;&nbsp;|</DIV>






<DIV>|&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;|_|&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;|___|&nbsp;&nbsp;&nbsp;|_____</DIV>






</p>

<h3><i>Can you guess the values of smpl1, smpl2 and smpl3 ? </i> </h3> 
</FONT>


<h2>Linux, here we come!</h2>

<p>The Linux kernel is an amazing piece of programming in that it has been
organized so well that a person with little or no knowledge of assembly language
can write a lot of kernel code (in fact 99% [wanna bet ? ;)] of the kernel is written in "c"). It is also designed in such a way that device driver writers are given a preset environment and an elegantly exhaustive programming interface to write code.</p>

<p>The kernel code is very portable, i.e., it can be compiled on a variety of
machines (processors like the i86, alpha, sparc). I think it makes good logic to
write code templates, which can be elaborated and tailor made for individual
hardware. In English, I can best illustrate this principle with an example. Suppose that you want to publish a PhD thesis on how to wash clothes using your brand of washing machine. You'd write a sequence of steps starting from:</p>

<p>1) Insert the power cord into the wall socket and switch on the power</p>

<p>...</p>

<p>n) Finally, retrieve your garments from the soaking mess and dump them on
the clothesline.</p>

<p>The sequence from 1 to n would take minor variations depending on whether
your washing machine was semi or fully automatic, whether it was top or side
loading (try step 'n' from the side loading washing machine, and send me an
e-mail about it) and other variables. The instructions in your thesis would be
fine for one washing machine, but how about if you were a freelance user
manual writer, and needed to write manuals for a thousand brands?</p>

<p>Take the case of the /dev/dsp device interface, the default interface for PCM
(pulse code modulated) and coded PCM sound. Hannu Savolainen designed much of
the interface, with Alan Cox making significant contributions. But these
designers--quite rightly--didn't make room for one teeny-weeny little device
called the PC-speaker, in favor of the AWE 64 and cards of the kind. They
assumed that all DSP devices would at least have DMA (Direct Memory Access is a
technique by which "intelligent" peripheral chips take care of moving data
to/from RAM, without involving the processor) support, or on board buffers, if
not coprocessors (i.e., on-board processors). So they put the DMA registration
code as a mandatory part of the OSS API. The OSS API has two levels of exported
functions: those exported by soundcore.o and another set exported by sound.o </p>

<p>sound.o is stacked on top of soundcore.o and uses its exported functions much the same as any other device driver. It provides an easy interface to portable device drivers and supports advanced functions like DMA access. (Modern sound cards support at least DMA ) </p>
<p>That's where we begin hacking. We have to avoid the standard OSS interface, and use the soundcore interface directly. Which means it's time for another technical discussion - character devices in Linux.</p>

<h2>Character Devices in Linux</h2>

<p>In Linux, there are mainly two kinds of devices: block and character.
(We're ignoring network devices since they aren't really "devices", more like
interfaces.)</p>

<p>Block devices are assumed to have certain characteristics like reading and
writing in blocks, buffering, partitioning etc. The hard disk drive is the
perfect example of a block device. An application normally accesses a hard
drive through a file system driver. That's why in Unix you mount disk drives
and do not access them sector-by-sector.</p>

<p>Character devices are meant to be read and written one byte at a time (e.g.:
the serial port), but are transparently buffered to improve system throughput. An
application accesses them by doing ordinary file operations on the
corresponding device nodes. Device nodes are special "files" which can be
accessed through the ordinary path tree. So if you want to write to the sound
device, by convention, /dev/dsp is the published device node to use for that.
Note that any device node that points to the corresponding device number
registered by the driver can be used to access that driver. For example, the
/dev/dsp node is attached to device number 14/3. (try: file /dev/dsp; on your
system). You could equally well access it via /dev/mynode if /dev/mynode points
to 14/3. Check the mknod man pages for exact semantics.</p>

<p>Now if you have a .wav file which is of a specific format, say 16-bit, stereo, raw pcm, to make it play on the system sound device, you might open the /dev/dsp node using the open system call, and open your .wav file, read a block of data from the .wav file, and write it to the /dev/dsp node using read and write system calls respectively. AHA! And guess what client is readily available for this? Our very own cp. So next time, try cp -f fart.wav /dev/dsp. And tell me how it sounded. I'll bet that unless you're very lucky, you wouldn't get the right sound even if you play Celine Dione. That's because the sound driver needs to be told what format the raw data it gets is in. More often than not, you'd be trying to play a 16-bit stereo file at 44khz on a 8-bit mono 8khz driver. That's like trying to play an LP disc at the wrong turntable speed.</p>

<p>The ioctl (short for input/output control) system call is used on /dev/dsp,
to talk to the device driver. Unfortunately, the exact semantics of the ioctl
call is left to the device driver writer's discretion. That's sort of like the
chaos one gets in the DOS software market. Thankfully, we have a few recognized
conventions in Linux, the most popular of which is the OSS or Open Sound System.
This is the interface implemented in Linux by Savolainen &amp; Co. So we have XMMS plug-ins for OSS on the application side, and scores of device drivers on the kernel side.</p>

<h2>The Kernel</h2>

<p>When an application makes the open "call" it's obviously calling something.
That something is a kernel routine (remember, <code>open</code> is a system call). The kernel
is designed to pass the call on to the corresponding device driver. The
amazingly nice thing about the Linux kernel is that you can tell the kernel to
call your routine for a particular device number. This is called device callback
registration, and is a kernel mode call, i.e., you cannot write applications
that do these calls and can be run from the terminal. Similarly you can play
kernel, and pass on user calls to further routines, if you design and export
your own custom registration functions. That's exactly what soundcore.o does via
register_sound_dsp().(Alright, alright, hold it, you ask me.  We'll dive into
the OSS sound modules soon. Just making sure that there's water in the pool!)
You use insmod for that, and write a special program called a kernel module,
which insmod can load into kernel space and link with the kernel system calls.
The main difference between system calls and kernel mode calls is that system
calls have to conform to general conventions if they are ever to be recognized
as a part of Unix.(Remember the "what is Linux" FAQ? ) The kernel, on the other
hand, is Linux. So it's just Linux conventions one has to follow in kernel
programming, and mind you, Linux kernel conventions change nine to the dozen per
kernel release. That's why you have a "pre-x.xx.xx version compile only "
warning with many releases of module binaries. At a minimum, we need to have a
read and write callback routine each, besides open and close. The Linux kernel
specifies a routine called init_module, and another called cleanup_module, which
are called by the kernel at the insertion and removal of our module. (Somewhat
like main() in user space.) In other words, when we write a init_module routine,
we assume that we have full control over the system ports, memory, etc. and that
we can call all available kernel functions. Another thing that's interesting is
that any kernel or module function can be exported to the kernel symbol table
(Check /proc/ksyms for a list) , so that it can get called by any other kernel
function or module. In other words, the kernel program file, /boot/vmlinuz,
originally was a C program starting with main() just like you or I would write
any other program in C. Only that the lines after the parenthesis were filled in by a very talented systems programmer called Linus Torvalds.</p>

<h2>Registering our driver</h2> <p>The most crucial part of the whole
discussion is of course the code itself. Registering the driver is done by
means of the register_sound_dsp function exported by the soundcore.o module,
which as I explained earlier, is part of the standard OSS distribution. What it
does is to pass through the <code>open</code> call from the user-space
application. Much of the code is self-explanatory. The GNU assembler
(originally AT&T assembler format) has to do with hooking the timer interrupt.
The setvect and getvect functions work much the same as they do in DOS. (OK go
ahead and say YUCK - I know you're lying. I wasn't born in Bell labs, you know
:) </p>


<h2>Towards A Working Device Driver</h2>

<p>For us, the main job is to get a working device driver that can access the
PC speaker through the 8254 timer ports, and do the tricks that'll copy the
application's sound data to the PC speaker, byte-by-byte.</p>

<p>OSS creates a device node called /dev/dsp for us. Our driver called
myaudio.o can be loaded into the running kernel using insmod myaudio.o,
and removed using rmmod myaudio. /dev/dsp points to our driver after the insmod.</p>

<p>Let's take a look at the program structure. We have the following tasks to
do:</p>

<p>1) Register our fake dsp device. 2) Hook the timer interrupt vector and set
the interrupt at the correct sampling rate. 3) Print a message that says Phew!
The kernel will tell you if anything went wrong. In many cases, it'll reboot
the system for you.</p>

<p>When the device is unloaded, we need to restore the system to its previous
state by the following steps:</p>

<p>4) Unhook the timer interrupt vector and reset the interrupt to the old
rate. 5) Unregister the dsp device. 6) Print a success message.</p>

<h2>A Look at myhandler()</h2>

<p>The sample code is in two files called myaudio.c and myaudio.h. myaudio.c
contains the device registration routines that do all the above tasks.
myaudio.h contains a very important routine called the ISR (Interrupt Service
Routine). It's named myhandler(). I think that the steps given above are
best explained by reading the code in myaudio.c. Let me turn your attention to
myaudio.h, to myhandler() in particular.</p>

<p>Step number 2 above says: "hook the timer interrupt vector". This means
that the ISR is to be setup in such a way as to get executed at exactly the
sampling rate we intend. This means that when I write the code in the ISR, I
can be reasonably sure of the following: a) The next datum from the user
application, if available, is to be fetched, b) It needs to be processed into
an 8254 counter 2 value (discussed in detail above), c) This counter value is
to be dumped into the 8254 counter 2 register: i.e. delay for the PC-speaker
is set according to the value of the fetched datum and d) The system scheduler
has not yet been called! Decide whether to call it.</p>

<p>Step d) needs an aside:</p>

<p>If you've read through setvect() in myaudio.c, you'll find that setvect
uses a few gimmicks to put myhandler into the system vector table. This is
Intel 386+ specific. In the real mode of 8086 operation, all one needs to do
to revector an ISR is to save the corresponding entry in the interrupt vector
table (IVT) that starts at memory address 0000:0000 in increments of 4 bytes.
(Because a fully qualified long pointer in the 8086 is 32bits long cs:ip.) In
other words, for interrupt 8, which is the default BIOS setting for IRQ 7, of
the PIC, just change the pointer value at 0000:0020 to the full address of
myhandler().Things are a little more complicated here. In 386+ protected mode,
in which the Linux kernel runs, the processor, the IVT is called the IDT, or
the Interrupt Descriptor Table. A meaningful description of the IDT would take
a whole HOWTO, but I'll assume that you know about 386+ protected mode if you
want to and save all the gory details for your PhD thesis. What we really need
to know is that the pointer to myhandler is scattered over an 8-byte area.
That information is put together using some cute GNU assembler statements to
make the original ISR memory pointer that actually points to the system
SCHEDULER (which is a special program routine in every multitasking operating
system) now point to myhandler(). The responsibility of the SCHEDULER is to pluck control from one
program when its time slice is over, and give control to the next. This is
called pre-emptive multitasking. In Linux, the time slice given to a process
is 10 milliseconds. Can you guess the rate at which the default timer ISR is
called? It's a value called HZ, in the Linux kernel.</p>

<p>The catch here is that while the original ISR (the scheduler) needs to be
called at 100Hz, our ISR requires calling at the sampling rate, usually
22Khz. And if we neglect to call the original ISR, all hell's going to break
loose. There's a simple solution waiting. If you know the rate at which you're
called, and the rate at which to call the original ISR, just call it once
every so many times. In other words: At 22Khz, increment a counter at
every tick and when the counter reaches 220, call the old ISR, otherwise, send
an EOI (End Of Interrupt) to the PIC. Thus the old ISR gets called at exactly
100Hz! Black Magic!! If you forget to compensate for the rates, it's very
interesting to observe what happens. Just try it. On my system, the minute
needle of xclock was spinning like a roulette wheel!</p>

<p>If you take a look at the figure above, the one which shows how the 8254
timer interrupt is hooked to the PIC, you'll notice that when the 8254 wants
to interrupt, it tells the PIC, via the IRQ 7 line, (which incidentally is
just a piece of copper wire embedded on the motherboard). Nowadays of course,
a number of the older chips are merged into one package so don't go around
snooping for a PCB trace labeled IRQ 7 on your motherboard! The PIC decides
whether, and when to interrupt the processor. This is a standard method to
share interrupts, and is called interrupt priority resolution (or
prioritization), which is the sole purpose of the PIC. In Linux, the PIC is
reprogrammed to call vector 20 for the timer ISR (IRQ 7) as against the vector
8 setting of the BIOS in DOS. After every interrupt, the corresponding ISR is
expected to do an EOI, which is essentially an outportb(0x20,0x20). So a
little care is needed to make sure you don't send a double EOI, one from you,
and one from the original ISR which doesn't know about you.</p>


<h2>One Last Point</h2>

<p>I guess, that's it, but before I run away satisfied that I've shoved Latin
up a thousand throats, I want to clear up a few things about the sample that I did
in myaudio.x . Linux has a formal method to claim interrupts for device
drivers. The trouble is, by the time a module is loaded, the scheduler has already
claimed the timer interrupt. So we have to hack a bit and steal it from the
scheduler. That's why we had to discuss IDTs and stuff. The OSS interface that
I've written in the code is pre-alpha. Actually, you can run applications like
mpg123, play and even xmms and you'll get insight into event synchronisation in
Multi-Multi Operation Systems if you add a -D SPKDBG to the compiler options
variable in myaudio.mak. The "-D SPKDBG" turns on debug messages. Be warned however,
that your machine may not be able to handle the overhead of recording the logs.
So do it only if you know what you are doing. I've elaborated OSS on a TODO
list earlier. You're welcome to complete it.</p>

<p>Do the following to use our driver:As root user, chdir to the directory where you've copied the source files
myaudio.c, myaudio.h, and myaudio.mak. Run:

<PRE>
make -f myaudio.mak
</PRE>

assuming that you have a standard OSS distribution on your machine. (The path
is /usr/src/linux/drivers/sound. Check it out.)

<PRE>
modprobe sound
insmod myaudio.o
</PRE>

<p>Now the driver is active. Check it with:

<PRE>lsmod
</PRE>

<p>Look for myaudio at the top of the list. mpg123, play and xmms should work like usual now.</p>

<p>If none of the above applications work, it's possible to listen to MP3 music with the following:

<PRE>
mpg123 -m -r 22000 --8bit -w /dev/dsp x.mp3 #this should playx.mp3
</PRE>

<p>ENJOY!!!!

<HR WIDTH="70%">

<b>Note: All these operations need to be done as user root. So I'm assuming
that you're using your own machine, and are ready to trash any part of it,
maybe permanently. I cannot take any responsibility for what happened to your
system because of my code, so I'll insist that you try it only at your own
risk. I tried my own sample on a Redhat 7.1 system running on a Celeron
366/64MB RAM. For a really, seriously, interested person who's bent on not
messing up his/her machine, kindly use the patches provided by Michael Beck,
but then you wouldn't be reading this, would you?

</b>

<HR WIDTH="70%">

<p><FONT COLOR="brown"> If your answer was in the order 
<PRE>
smpl1&gt;smpl2&gt;smpl3, and smpl2=127 
</PRE> then you've passed the test. You may now apply to Creative labs ;)
</FONT>

<HR WIDTH="70%">

Program listing:
<ul>
<li> <A HREF="misc/mathew/myaudio.h.txt">myaudio.h</A>
<li> <A HREF="misc/mathew/myaudio.c.txt">myaudio.c</A>
<li> <A HREF="misc/mathew/Makefile.txt">Makefile</A>
</ul>




<!-- *** BEGIN bio *** -->
<SPACER TYPE="vertical" SIZE="30">
<P> 
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Cherry George Mathew</H4>
<EM>I'm a third year Electronics Engineering undergraduate student at College of
Engineering, Adoor, Kerala, India.   You may contact me at at <a
href="http://berryplum.homestead.com/">http://berryplum.homestead.com/</a> or
<a href="mailto:berryplumis@yahoo.com">berryplumis@yahoo.com</a>, and time
permitting I will try to answer.</EM>

<!-- *** END bio *** -->

<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P --> 
<H5 ALIGN=center>

Copyright &copy; 2001, Cherry George Mathew and Linux.com.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR> 
Published in Issue 69 of <i>Linux Gazette</i>, August 2001</H5>
<!-- *** END copyright *** -->


<H4 ALIGN="center">
"Linux Gazette...<I>making Linux just a little more fun!</I>"
</H4>

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

<center>
<H1><font color="maroon">Combining Perl and PostgreSQL, Part 2: Procedures with PL/pgSQL</font></H1>
<H4>By <a href="mailto:articles@gnujobs.com">Mark Nielsen</a></H4>
</center>
<P> <HR> <P>  

<!-- END header -->




<p>
<ol>
<li>
<a href="#Introduction">Introduction</a></li>
<li><a href="#perl">Perl script to create tables, procedures, 
backup tables, and sequences. 
</a></li>
<li><a href="#execute">Executing the Perl script</a></li>
<li><a href="#consider">Considerations to explore.</a></li>
<li><a href="#Conclusion">Conclusion</a></li>
<li><a href="#REF">References</a></li>
</ol>

<h3><a NAME="Introduction"></a>Introduction</h3>
After dealing with installing PostgreSQL, Perl, and embedding Perl in
PostgreSQL, I wanted a standard way to create tables, sequences, 
stored procedures, and backup tables. Perhaps other people have nice GUI
solutions to do this, but I haven't seen any. I would like it if someone
would work with me to create a GUI interface to achieve what I am doing here. 
My goals are:
<ol>
<li> Always backup data no matter what happens. </li>
<li> Always use stored procedures to insert, update, delete, copy, or
  to do anything that changes data on the tables. One should even create
  stored procedures to select data. </li>
<li> Have a Perl script create tables, sequences, backups tables, and the
  stored procedures to manipulate the data. </li>
<li>Have the stored procedures clean data using Perl. </li> 
<li>Backup data if someone runs the Perl script on a live system.</li>
<li> There should be an active column in the table so that you can specify
active or inactive rows in the table. We create a view which views 
active rows of a table. </li>
<li> Stored procedures should record date created and date last updated. 
</li>
<li>All rows have a unique id. Even if we choose not to use them, 
they will still have them. It is not always good to use oid to get
unique rows. </li>
<li> Be able to delete inactive rows 
with a purge procedure. The delete procedure
just makes it inactive. Also, unpurge data with the latest purged
data for a unique id. This
is cool.</li> 
<li> All negative numbers returned from pl/sql procedures are considered
failures. All positive numbers (including 0) are considered to be
successes in the fact nothing errored out. They are either 0, in which
nothing happened, or something greater than 0 which indicates the
number of items affected or a id number. </li>
</ol>
My future goals include:
<ol>
<li> Creating a GUI interface. Preferrably one that is not dependent on GNOME
or KDE libraries but Python. You can create Python binaries easily, so I 
would prefer Python/TK.</li>
<li>Allow the GUI design to make changes to live tables by either:
  <ul>
  <li>Making updates that really happen with full effects. Some changes
   con't allow all options (at least in the past). </li>
  <li>Creating a new table, and dumping all the data from the old table
  into the new one while locking the old table.  </li>
  </ul>
</li>
<li>Record all database changes to review history.</li>
</ol>

<h3><a NAME="perl"></a>Perl script to create tables, procedures,
backup tables, and sequences.</h3>
Here is the Perl script I use. You can also get a copy here
<a href="misc/nielsen/Create_Functions.pl.txt">Create_Functions.pl.txt</a>.
<pre>
#!/usr/bin/perl

#              Create Functions for Perl/PostgreSQL version 0.1

#                       Copyright 2001, Mark Nielsen
#                            All rights reserved.
#    This Copyright notice was copied and modified from the Perl 
#    Copyright notice. 
#    This program is free software; you can redistribute it and/or modify
#    it under the terms of either:

#        a) the GNU General Public License as published by the Free
#        Software Foundation; either version 1, or (at your option) any
#        later version, or

#        b) the "Artistic License" which comes with this Kit.

#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See either
#    the GNU General Public License or the Artistic License for more details.

#    You should have received a copy of the Artistic License with this
#    Kit, in the file named "Artistic".  If not, I'll be glad to provide one.

#    You should also have received a copy of the GNU General Public License
#   along with this program in the file named "Copying". If not, write to the 
#   Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 
#    02111-1307, USA or visit their web page on the internet at
#    http://www.gnu.org/copyleft/gpl.html.

use strict;

  ### We want to define some variables WHICH YOU SHOULD CHANGE FOR YOUR
  ### OWN COMPUTER. 
my $Home = "/tmp/testdir";
my $File = "$Home/Tables.txt";
my $Template = "$Home/Generic.fun";
my $Custom = "$Home/Custom.sql";
my $Database = "testdatabase";
 
#------------------------------------------------------------------------

my @List = @ARGV;

  ## Let us create the two directories we need if they are not there. 
if (!(-e "$Home/Tables")) {system "mkdir -p $Home/Tables"}
if (!(-e "$Home/Backups")) {system "mkdir -p $Home/Backups"}

  ### Open up the template for the functions and the file that contains
  ### the info to create the tables. 
open(FILE,$Template); my @Template = &lt;FILE&gt;; close FILE;
open(FILE,$File); my @File = &lt;FILE&gt;; close FILE;
open(FILE,$Custom); my @Custom = &lt;FILE&gt;; close FILE;

  ### Filter out lines that have no numbers or letters. 
@File = grep($_ =~ /[a-z0-9]/i, @File);
  ### Get rid of any line which contains a #
@File = grep(!($_ =~ /\#/), @File);
  ### Get rid of the newline. 
grep(chomp $_, @File);
  ### Get rid of tabs and replace with spaces. . 
grep($_ =~ s/\t/ /g, @File);
  ### Convert all multiple spaces to one.  
grep($_ =~ s/  +/ /g, @File);
  ### Next two lines get rid of spaces and front and end.  
grep($_ =~ s/^ //g, @File);
grep($_ =~ s/ $//g, @File);
  ### Delete any commas at the end, we will put them back on later. 
grep($_ =~ s/\,$//g, @File);

my $Tables = {};
my $TableName = "";
  ### For each line in the file, either make a new array for the table, 
  ### or store the lines in the array for a table.  
foreach my $Line (@File)  
  {
  my $Junk = "";
    ### If the line starts with "TABLENAME" then create a new array. 
  if ($Line =~ /^TABLENAME/) 
    {
    ($Junk,$TableName, $Junk) = split(/ /,$Line);
       ### This creates the aray for the table. 
    $Tables-&gt;{$TableName} = [];
    }
  else 
    {
       ### Storing lines for the table. 
    push (@{$Tables-&gt;{$TableName}}, $Line) ;
    }
  }

    ### If we listed specific tables, then only do those. 
  if (@List) 
    {
    foreach my $TableName (sort keys %$Tables)
      { if (!(grep($_ eq $TableName, @List))) {delete $Tables-&gt;{$TableName};} }
    }

  ### Get the keys of the reference to an array $Tables
  ### and get the data for that array, create our file, and then use the file. 
foreach my $TableName (sort keys %$Tables) 
  {
  my @Temp = @{$Tables-&gt;{$TableName}};

  my $Backup_Columns = "";  my $Backup_Values = ""; my $Update_Fields = "";
  my $Field_Copy_Values = "";  my $FieldTypes = "";
  my $CleanVariables = ""; my $RemakeVariables = ""; 
    ### The two tables are different in one respect, the backup table 
    ### does not require uniqueness and it doesn't use a sequence.  
  my $Table = qq($TableName\_id int4 NOT NULL UNIQUE DEFAULT nextval('$TableName\_sequence'),
    date_updated  timestamp NOT NULL default CURRENT_TIMESTAMP,
    date_created  timestamp NOT NULL default CURRENT_TIMESTAMP,
    active int2 CHECK (active in (0,1)) DEFAULT 0,
);
    ## I should allow null for the id instead of 0, but since the sequence
    ### starts at 1, I use 0 as null. I hate nulls.  
  my $Table_Backup = qq(backup_id int4 NOT NULL UNIQUE DEFAULT nextval('$TableName\_sequence_backup'), 
    $TableName\_id int4 NOT NULL DEFAULT 0,
    date_updated  timestamp NOT NULL default CURRENT_TIMESTAMP,
    date_created  timestamp NOT NULL default CURRENT_TIMESTAMP,
    active int2 CHECK (active in (0,1)) DEFAULT 0,
    );

  print "Creating functions for table '$TableName'\n";
  my $No = 1;
    ### For each line for this table do this. 
    ### We want to create a few variables that are going to be placed into
    ### the template.  
  foreach my $Line (@Temp) 
    {
    $Table .= "$Line,\n";
    $Table_Backup .= "$Line,\n";
    my ($Name,$Type,$Ext) = split(/ /,$Line,3);
      ### The backup columns
    $Backup_Columns .= ", $Name"; 
      ### The update fields
    $No++; $Update_Fields .= ", $Name = var_$No"; 
      ### Backup values
    $Backup_Values .= ", record_backup.$Name";
      ### Now the fields when we copy stuff in the cyop function. 
    $Field_Copy_Values .= ", clean_text(record2.$Name)";
      ### Now the field types for the update function. 
    $FieldTypes .= ", $Type";
      ### We need to define the variables for the updating function.
    $CleanVariables .= "          var_$No $Type;\n";
      ### We need to define the type, I only check for text and int4 for now. 
    my $Temp = "\$$No";  
    if ($Type eq "int4") {$Temp = "clean_numeric($Temp)";}
    elsif  ($Type eq "text") {$Temp = "clean_text($Temp)";}
      ### Now we need to set the variables. 
    $RemakeVariables .= "         var_$No := $Temp;\n";

     ### We also need to add the function to clean out he variables before
     ### they are submitted. 
    }
   ### Record how many rows we had. Make a line for the update command for
   ### testing. 
  my $Number_Of_Rows = $No;
  my $Update_Test = "1";
  for (my $i = 1; $i &lt; $Number_Of_Rows - 1; $i++) {$Update_Test .= ",$i";}

    ### We need to chop off the last comma. 
  chomp $Table; chop $Table; chomp $Table_Backup; chop $Table_Backup;
    ### Now let us setup dropping and creating of the table and backup table. 
  my $Tables = qq(drop table $TableName;\ncreate table $TableName (\n$Table\n);); 
  $Tables .= "drop table $TableName\_backup;\n";
  $Tables .= "create table $TableName\_backup (\n$Table_Backup, error_code text NOT NULL DEFAULT ''\n);\n";
    ### Let us create a view for active stuff in our table. 
  $Tables .= "drop view $TableName\_active;\n";
  $Tables .= "create view $TableName\_active as select * from $TableName
        where active = 1;\n";
    ### Create a view for inactive or deleted items. 
  $Tables .= "drop view $TableName\_deleted;\n";
  $Tables .= "create view $TableName\_deleted as select * from $TableName
        where active = 0;\n";
    ### Create a view for a list of unique backup ids. 
  $Tables .= "drop view $TableName\_backup_ids;\n";
  $Tables .= "create view $TableName\_backup_ids as 
           select distinct $TableName\_id from $TableName\_backup;\n";
    ### Create a list of purged data (lastest data per id).  
  $Tables .= "drop view $TableName\_purged;\n";
  $Tables .= "create view $TableName\_purged as
   select * from $TableName\_backup where oid = ANY (
     select max(oid) from $TableName\_backup where $TableName\_id = ANY
        (
        select distinct $TableName\_id from $TableName\_backup
          where $TableName\_backup.error_code = 'purge'
           and NOT $TableName\_id = ANY (select $TableName\_id from $TableName)
        )
        group by $TableName\_id
     )
    ;\n";

     ### I use grep commands to search and replace stuff for arrays.
     ### I could use map, but I like greps.  
  my @Temp = @Template;
     ### now add the custom sql commands. 
  push (@Temp,@Custom);

  grep($_ =~ s/TABLENAME/$TableName/g, @Temp);
  grep($_ =~ s/BACKUPCOLUMNS/$Backup_Columns/g, @Temp);
  grep($_ =~ s/BACKUPVALUES/$Backup_Values/g, @Temp);
  grep($_ =~ s/UPDATEFIELDS/$Update_Fields/g, @Temp);
  grep($_ =~ s/COPYFIELDS/$Field_Copy_Values/g, @Temp);
  grep($_ =~ s/FIELDS/$FieldTypes/g, @Temp);
  grep($_ =~ s/HOME/$Home/g, @Temp);
  grep($_ =~ s/CLEANVARIABLES/$CleanVariables/g, @Temp);
  grep($_ =~ s/REMAKEVARIABLES/$RemakeVariables/g, @Temp);

    ### Now move the stuff from the array @Temp to @Template_Copy.
  my @Template_Copy = @Temp;

    ### Now we save the file. We won't delete it (unless you run this script
    ### again) so that we can figure out what was done.  
  open(FILE,"&gt;$Home/Tables/$TableName\.table_functions");
    ### Create the sequence for the table . 
  print FILE "drop sequence $TableName\_sequence;\n";
  print FILE "create sequence $TableName\_sequence;\n";
  print FILE "drop sequence $TableName\_sequence_backup;\n";
  print FILE "create sequence $TableName\_sequence_backup;\n";
    ### Print out the table and backup table.   
  print FILE $Tables;
    ### Print out the 4 functions, insert, delete, update, and copy. 
  foreach my $Temp (@Template_Copy) {print FILE "$Temp";} 

  close FILE;

    ### Before we execute, let us backup the table in case some novice 
    ### executes this on a live server. 
  my $Backup_File = "$Home/Backups/$TableName\_0.backup";
  my $No = 0;
  while (-e $Backup_File)
    {$No++; $Backup_File = "$Home/Backups/$TableName\_$No\.backup";} 
    ### Now we have the filename to store the backup, execute it. 
  system ("pg_dump -t $TableName -f $Backup_File $Database");
  
  ### Uncomment this option if you want to see what is in the file. 
##  system ("cat $Home/Tables/$TableName\.table_functions");

    ### Drop table and functions, create table and functions and backup table. 
  system ("psql -d $Database -c '\\i $Home/Tables/$TableName\.table_functions'");
  print "Check the file\n $Home/Tables/$TableName\.table_functions.\n";

  } 



</pre>
Rename the perl script "Create_Functions.pl.txt". Here are the things
needed to get it to work:
<ul>
<li>You must change the options above the dotted line. </li>
<li> You must have PostgreSQL installed with Perl embedded in it. 
<li>Enter the command "psql template1". Then type "create database
testdatabase;" or whatever you named your database. Press enter. If you have
errors along the way, you haven't set up the permissions yet. Login in as
root, then execute "su -l postgres". Then type "createuser" and press
enter. This will create a user in your postgresql database. Enter in the
username and give the username full privledges. Then try again 
with your normal account. </li> 
</ul>

<h3><a NAME="execute"></a>Executing the Perl script </h3>
You will need some more files. The <a href="misc/nielsen/Tables.txt">Tables.txt</a> file.  
<pre>

TABLENAME contact
question_id int4 NOT NULL DEFAULT 0
company_name text NOT NULL default ''
first  text NOT NULL default ''
middle text NOT NULL default ''
last text NOT NULL default ''
email  text NOT NULL default ''
work_phone text NOT NULL default ''
home_phone text NOT NULL default ''
address_1 text NOT NULL default '',
address_2 text NOT NULL default ''
city text NOT NULL default ''
state text NOT NULL default ''
zip text NOT NULL default ''

TABLENAME account
username text NOT NULL DEFAULT '',
password text not NULL DEFAULT '',

TABLENAME contact_lists
account_id int4 not null default 0,
contact_id int4 not null default 0,
</pre>
You can use my file as an example, but I suggest to modify it for your
own needs. It is simulated to make three tables. One containing userame
and passwords, and the other associating a username to a list of
contacts.  Another file you will need is <a href="misc/nielsen/Generic.fun">Generic.fun</a>
<pre>
---              Generic Functions for Perl/Postgresql version 0.1

---                       Copyright 2001, Mark Nielsen
---                            All rights reserved.
---    This Copyright notice was copied and modified from the Perl 
---    Copyright notice. 
---    This program is free software; you can redistribute it and/or modify
---    it under the terms of either:

---        a) the GNU General Public License as published by the Free
---        Software Foundation; either version 1, or (at your option) any
---        later version, or

---        b) the "Artistic License" which comes with this Kit.

---    This program is distributed in the hope that it will be useful,
---    but WITHOUT ANY WARRANTY; without even the implied warranty of
---    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See either
---    the GNU General Public License or the Artistic License for more details.

---    You should have received a copy of the Artistic License with this
---    Kit, in the file named "Artistic".  If not, I'll be glad to provide one.

---    You should also have received a copy of the GNU General Public License
---   along with this program in the file named "Copying". If not, write to the 
---   Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 
---    02111-1307, USA or visit their web page on the internet at
---    http://www.gnu.org/copyleft/gpl.html.

-- create a method to unpurge just one item.  
-- create a method to purge one item. 
--  \i HOME/TABLENAME.table
---------------------------------------------------------------------

drop function sql_TABLENAME_insert ();
CREATE FUNCTION sql_TABLENAME_insert () RETURNS int4 AS '
DECLARE
    record1 record;  oid1 int4; id int4 :=0; record_backup RECORD;
BEGIN
   insert into TABLENAME (date_updated, date_created, active)
        values (CURRENT_TIMESTAMP,CURRENT_TIMESTAMP, 1);
     -- Get the unique oid of the row just inserted. 
   GET DIAGNOSTICS oid1 = RESULT_OID;
     -- Get the TABLENAME id. 
   FOR record1 IN SELECT TABLENAME_id FROM TABLENAME where oid = oid1
      LOOP
      id := record1.TABLENAME_id;
   END LOOP;
   
     -- If id is NULL, insert failed or something is wrong.
   IF id is NULL THEN return (-1); END IF;
     -- It should also be greater than 0, otherwise something is wrong.
   IF id &lt; 1 THEN return (-2); END IF;

      -- Now backup the data. 
    FOR record_backup IN SELECT * FROM TABLENAME where TABLENAME_id = id
       LOOP
       insert into TABLENAME_backup (TABLENAME_id, date_updated, date_created, 
           active, error_code) 
         values (id, record_backup.date_updated, record_backup.date_created,
            record_backup.active, ''insert'');
    END LOOP;

     -- Everything has passed, return id as TABLENAME_id.
   return (id);
END;
' LANGUAGE 'plpgsql';
---------------------------------------------------------------------

drop function sql_TABLENAME_delete (int4);
CREATE FUNCTION sql_TABLENAME_delete (int4) RETURNS int2 AS '
DECLARE
    id int4 := 0;
    id_exists int4 := 0;
    record1 RECORD; 
    record_backup RECORD;
    return_int4 int4 :=0;

BEGIN
     -- If the id is not greater than 0, return error.
   id := clean_numeric($1);
   IF id &lt; 1 THEN return -1; END IF;

     -- If we find the id, set active = 0. 
   FOR record1 IN SELECT TABLENAME_id FROM TABLENAME 
          where TABLENAME_id = id
      LOOP
      update TABLENAME set active=0, date_updated = CURRENT_TIMESTAMP
           where TABLENAME_id = id;  
      GET DIAGNOSTICS return_int4 = ROW_COUNT;       
      id_exists := 1;
   END LOOP;
      
     -- If we did not find the id, abort and return -2.  
   IF id_exists = 0 THEN return (-2); END IF;

   FOR record_backup IN SELECT * FROM TABLENAME where TABLENAME_id = id
      LOOP
      insert into TABLENAME_backup (TABLENAME_id, date_updated, date_created,
          active BACKUPCOLUMNS ,error_code)
           values (record_backup.TABLENAME_id, record_backup.date_updated, 
             record_backup.date_updated, record_backup.active
             BACKUPVALUES , ''delete''
      );
   END LOOP;

     -- If id_exists == 0, Return error.
     -- It means it never existed. 
   IF id_exists = 0 THEN return (-1); END IF;

     -- We got this far, it must be true, return ROW_COUNT.   
   return (return_int4);
END;
' LANGUAGE 'plpgsql';

---------------------------------------------------------------------
drop function sql_TABLENAME_update (int4 FIELDS);
CREATE FUNCTION sql_TABLENAME_update  (int4 FIELDS) 
  RETURNS int2 AS '
DECLARE
    id int4 := 0;
    id_exists int4 := 0;
    record_update RECORD; record_backup RECORD;
    return_int4 int4 :=0;
    CLEANVARIABLES
BEGIN
    REMAKEVARIABLES
     -- If the id is not greater than 0, return error.
   id := clean_numeric($1);
   IF id &lt; 1 THEN return -1; END IF;

   FOR record_update IN SELECT TABLENAME_id FROM TABLENAME
         where TABLENAME_id = id
      LOOP
      id_exists := 1;
   END LOOP;

   IF id_exists = 0 THEN return (-2); END IF;

   update TABLENAME set date_updated = CURRENT_TIMESTAMP
      UPDATEFIELDS 
        where TABLENAME_id = id;
   GET DIAGNOSTICS return_int4 = ROW_COUNT;

   FOR record_backup IN SELECT * FROM TABLENAME where TABLENAME_id = id
      LOOP
     insert into TABLENAME_backup (TABLENAME_id,
         date_updated, date_created, active
         BACKUPCOLUMNS, error_code)
       values (record_update.TABLENAME_id, record_backup.date_updated,
         record_backup.date_updated, record_backup.active
         BACKUPVALUES, ''update''
      );
   END LOOP;

     -- We got this far, it must be true, return ROW_COUNT.   
   return (return_int4);
END;
' LANGUAGE 'plpgsql';
---------------------------------------------------------------------

drop function sql_TABLENAME_copy (int4);
CREATE FUNCTION sql_TABLENAME_copy (int4) 
  RETURNS int2 AS '
DECLARE
    id int4 := 0;
    id_exists int4 := 0;
    record1 RECORD; record2 RECORD; record3 RECORD;    
    return_int4 int4 := 0;
    id_new int4 := 0;
    TABLENAME_new int4 :=0;
BEGIN
     -- If the id is not greater than 0, return error.
   id := clean_numeric($1);
   IF id &lt; 1 THEN return -1; END IF;

   FOR record1 IN SELECT TABLENAME_id FROM TABLENAME where TABLENAME_id = id
      LOOP
      id_exists := 1;
   END LOOP;
   IF id_exists = 0 THEN return (-2); END IF;

     --- Get the new id
   FOR record1 IN SELECT sql_TABLENAME_insert() as TABLENAME_insert
      LOOP
      TABLENAME_new := record1.TABLENAME_insert;
   END LOOP;
     -- If the TABLENAME_new is not greater than 0, return error.
   IF TABLENAME_new &lt; 1 THEN return -3; END IF;

   FOR record2 IN SELECT * FROM TABLENAME where TABLENAME_id = id
      LOOP

     FOR record1 IN SELECT sql_TABLENAME_update(TABLENAME_new COPYFIELDS)
        as TABLENAME_insert
      LOOP
        -- execute some arbitrary command just to get it to pass. 
      id_exists := 1;
     END LOOP;
   END LOOP;

     -- We got this far, it must be true, return new id.   
   return (TABLENAME_new);
END;
' LANGUAGE 'plpgsql';

------------------------------------------------------------------
drop function sql_TABLENAME_purge ();
CREATE FUNCTION sql_TABLENAME_purge () RETURNS int4 AS '
DECLARE
    record_backup RECORD; oid1 int4 := 0;
    return_int4 int4 :=0;
    deleted int4 := 0;
    delete_count int4 :=0;
    delete_id int4;

BEGIN 

     -- Now delete one by one. 
   FOR record_backup IN SELECT * FROM TABLENAME where active = 0
      LOOP
         -- Record the id we want to delete. 
      delete_id = record_backup.TABLENAME_id;

      insert into TABLENAME_backup (TABLENAME_id, date_updated, date_created,
          active BACKUPCOLUMNS ,error_code)
           values (record_backup.TABLENAME_id, record_backup.date_updated, 
             record_backup.date_updated, record_backup.active
             BACKUPVALUES , ''purge''
          );

        -- Get the unique oid of the row just inserted. 
      GET DIAGNOSTICS oid1 = RESULT_OID;

        -- If oid1 less than 1, return -1
      IF oid1 &lt; 1 THEN return (-2); END IF;
        -- Now delete this from the main table.   
      delete from TABLENAME where TABLENAME_id = delete_id;

        -- Get row count of row just deleted, should be 1. 
      GET DIAGNOSTICS deleted = ROW_COUNT;
        -- If deleted less than 1, return -3
      IF deleted &lt; 1 THEN return (-3); END IF;
      delete_count := delete_count + 1;

    END LOOP;

     -- We got this far, it must be true, return the number of ones we had.  
   return (delete_count);
END;
' LANGUAGE 'plpgsql';

------------------------------------------------------------------
drop function sql_TABLENAME_purgeone (int4);
CREATE FUNCTION sql_TABLENAME_purgeone (int4) RETURNS int4 AS '
DECLARE
    record_backup RECORD; oid1 int4 := 0;
    record1 RECORD;
    return_int4 int4 :=0;
    deleted int4 := 0;
    delete_count int4 :=0;
    delete_id int4;
    purged_no int4 := 0;

BEGIN

    delete_id := $1;
        -- If purged_id less than 1, return -4
    IF delete_id &lt; 1 THEN return (-4); END IF;

   FOR record1 IN SELECT * FROM TABLENAME 
      where active = 0 and TABLENAME_id = delete_id 
      LOOP
      purged_no := purged_no + 1;
   END LOOP;

        -- If purged_no less than 1, return -1
   IF purged_no &lt; 1 THEN return (-1); END IF;

     -- Now delete one by one.
   FOR record_backup IN SELECT * FROM TABLENAME where TABLENAME_id = delete_id
      LOOP

      insert into TABLENAME_backup (TABLENAME_id, date_updated, date_created,
          active BACKUPCOLUMNS ,error_code)
           values (record_backup.TABLENAME_id, record_backup.date_updated,
             record_backup.date_updated, record_backup.active
             BACKUPVALUES , ''purgeone''
          );

        -- Get the unique oid of the row just inserted.
      GET DIAGNOSTICS oid1 = RESULT_OID;

        -- If oid1 less than 1, return -2
      IF oid1 &lt; 1 THEN return (-2); END IF;
        -- Now delete this from the main table.
      delete from TABLENAME where TABLENAME_id = delete_id;

        -- Get row count of row just deleted, should be 1.
      GET DIAGNOSTICS deleted = ROW_COUNT;
        -- If deleted less than 1, return -3
      IF deleted &lt; 1 THEN return (-3); END IF;
      delete_count := delete_count + 1;

    END LOOP;

     -- We got this far, it must be true, return the number of ones we had.
   return (delete_count);
END;
' LANGUAGE 'plpgsql';

------------------------------------------------------------------------
drop function sql_TABLENAME_unpurge ();
CREATE FUNCTION sql_TABLENAME_unpurge () RETURNS int2 AS '
DECLARE
    record1 RECORD;
    record2 RECORD; 
    record_backup RECORD;
    purged_id int4 := 0;
    purge_count int4 :=0;
    timestamp1 timestamp;
    purged_no int4 := 0;
    oid1 int4 := 0;
    oid_found int4 := 0;
    highest_oid int4 := 0;

BEGIN

     -- Now get the unique ids that were purged. 
   FOR record1 IN select distinct TABLENAME_id from TABLENAME_backup 
       where TABLENAME_backup.error_code = ''purge''
          and NOT TABLENAME_id = ANY (select TABLENAME_id from TABLENAME)
      LOOP

      purged_id := record1.TABLENAME_id;
      timestamp1 := CURRENT_TIMESTAMP;
      purged_no := purged_no + 1;
      oid_found := 0;
      highest_oid := 0;

        -- Now we have the unique id, find its latest date. 

      FOR record2 IN select max(oid) from TABLENAME_backup 
          where TABLENAME_id = purged_id and error_code = ''purge''
        LOOP 
          -- record we got the date and also record the highest date.
        oid_found := 1; 
        highest_oid := record2.max;
      END LOOP;
 
         -- If the oid_found is 0, return error. 
      IF oid_found = 0 THEN return (-3); END IF;

        -- Now we have the latest date, get the values and insert them. 
      FOR record_backup IN select * from TABLENAME_backup 
          where oid = highest_oid
        LOOP 

      insert into TABLENAME_backup (TABLENAME_id, date_updated, date_created,
          active BACKUPCOLUMNS ,error_code)
           values (purged_id, record_backup.date_updated, 
             timestamp1, record_backup.active
             BACKUPVALUES , ''unpurge''
          );

        -- Get the unique oid of the row just inserted. 
      GET DIAGNOSTICS oid1 = RESULT_OID;
        -- If oid1 less than 1, return -1
      IF oid1 &lt; 1 THEN return (-1); END IF;

      insert into TABLENAME (TABLENAME_id, date_updated, date_created,
          active BACKUPCOLUMNS)
           values (purged_id, timestamp1,
             timestamp1, record_backup.active
             BACKUPVALUES );
        -- Get the unique oid of the row just inserted.
      GET DIAGNOSTICS oid1 = RESULT_OID;
        -- If oid1 less than 1, return -2
      IF oid1 &lt; 1 THEN return (-2); END IF;

      END LOOP;

   END LOOP;

     -- We got this far, it must be true, return how many were affected.  
   return (purged_no);
END;
' LANGUAGE 'plpgsql';

---------------------------------------------------------------------
drop function sql_TABLENAME_unpurgeone (int4);
CREATE FUNCTION sql_TABLENAME_unpurgeone (int4) RETURNS int2 AS '
DECLARE
    record_id int4;
    record1 RECORD;
    record2 RECORD;
    record_backup RECORD;
    return_int4 int4 :=0;
    purged_id int4 := 0;
    purge_count int4 :=0;
    timestamp1 timestamp;
    purged_no int4 := 0;
    oid1 int4 := 0;
    oid_found int4 := 0;
    highest_oid int4 := 0;

BEGIN

      purged_id := $1;
        -- If purged_id less than 1, return -1
      IF purged_id &lt; 1 THEN return (-1); END IF;
        --- Get the current timestamp.
      timestamp1 := CURRENT_TIMESTAMP;

   FOR record1 IN select distinct TABLENAME_id from TABLENAME_backup
       where TABLENAME_backup.error_code = ''purge''
          and NOT TABLENAME_id = ANY (select TABLENAME_id from TABLENAME)
          and TABLENAME_id = purged_id
      LOOP
      purged_no := purged_no + 1;

   END LOOP;

        -- If purged_no less than 1, return -1
   IF purged_no &lt; 1 THEN return (-3); END IF;

        -- Now find the highest oid.  
   FOR record2 IN select max(oid) from TABLENAME_backup
          where TABLENAME_id = purged_id and error_code = ''purge''
        LOOP
          -- record we got the date and also record the highest date.
        oid_found := 1;
        highest_oid := record2.max;
    END LOOP;

         -- If the oid_found is 0, return error.
    IF oid_found = 0 THEN return (-4); END IF;

        -- Now get the data and restore it. 
    FOR record_backup IN select * from TABLENAME_backup 
          where oid  = highest_oid
        LOOP 
        -- Insert into backup that it was unpurged. 
      insert into TABLENAME_backup (TABLENAME_id, date_updated, date_created,
          active BACKUPCOLUMNS ,error_code)
           values (purged_id, timestamp1, 
             record_backup.date_created, record_backup.active
             BACKUPVALUES , ''unpurgeone''
          );

        -- Get the unique oid of the row just inserted. 
      GET DIAGNOSTICS oid1 = RESULT_OID;
        -- If oid1 less than 1, return -1
      IF oid1 &lt; 1 THEN return (-1); END IF;
        -- Insert into live table. 
      insert into TABLENAME (TABLENAME_id, date_updated, date_created,
          active BACKUPCOLUMNS)
           values (record_backup.TABLENAME_id, timestamp1,
             record_backup.date_updated, record_backup.active
             BACKUPVALUES );
        -- Get the unique oid of the row just inserted.
      GET DIAGNOSTICS oid1 = RESULT_OID;
        -- If oid1 less than 1, return -2
      IF oid1 &lt; 1 THEN return (-2); END IF;

      END LOOP;

     -- We got this far, it must be true, return how many were affected (1).  
   return (purged_no);
END;
' LANGUAGE 'plpgsql';





</pre>

and lastly <a href="misc/nielsen/Custom.sql">Custom.sql</a>. 
<pre>
---          Custom Sample SQL for Perl/PostgreSQL version 0.1

---                       Copyright 2001, Mark Nielsen
---                            All rights reserved.
---    This Copyright notice was copied and modified from the Perl 
---    Copyright notice. 
---    This program is free software; you can redistribute it and/or modify
---    it under the terms of either:

---        a) the GNU General Public License as published by the Free
---        Software Foundation; either version 1, or (at your option) any
---        later version, or

---        b) the "Artistic License" which comes with this Kit.

---    This program is distributed in the hope that it will be useful,
---    but WITHOUT ANY WARRANTY; without even the implied warranty of
---    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See either
---    the GNU General Public License or the Artistic License for more details.

---    You should have received a copy of the Artistic License with this
---    Kit, in the file named "Artistic".  If not, I'll be glad to provide one.

---    You should also have received a copy of the GNU General Public License
---   along with this program in the file named "Copying". If not, write to the 
---   Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 
---    02111-1307, USA or visit their web page on the internet at
---    http://www.gnu.org/copyleft/gpl.html.

drop function clean_text (text);
CREATE FUNCTION  clean_text (text) RETURNS text AS '
  my $Text = shift;
    # Get rid of whitespace in front. 
  $Text =~ s/^\\s+//;
    # Get rid of whitespace at end. 
  $Text =~ s/\\s+$//;
    # Get rid of anything not text.
  $Text =~ s/[^ a-z0-9\\/\\`\\~\\!\\@\\#\\$\\%\\^\\&\\*\\(\\)\\-\\_\\=\\+\\\\\\|\[\\{\\]\\}\\;\\:\\''\\"\\,\\&lt;\\.\\&gt;\\?\\t\\n]//gi;
    # Replace all multiple whitespace with one space. 
  $Text =~ s/\\s+/ /g;
  return $Text;
' LANGUAGE 'plperl';
 -- Just to show you what this function cleans up. 
select clean_text ('       ,./&lt;&gt;?aaa aa      !@#$%^&*()_+| ');

drop function clean_alpha (text);
CREATE FUNCTION  clean_alpha (text) RETURNS text AS '
  my $Text = shift;
  $Text =~ s/[^a-z0-9_]//gi;
  return $Text;
' LANGUAGE 'plperl';
 -- Just to show you what this function cleans up. 
select clean_alpha ('       ,./&lt;&gt;?aaa aa      !@#$%^&*()_+| ');

drop function clean_numeric (text);
CREATE FUNCTION  clean_numeric (text) RETURNS int4 AS '
  my $Text = shift;
  $Text =~ s/[^0-9]//gi;
  return $Text;
' LANGUAGE 'plperl';
 -- Just to show you what this function cleans up.
select clean_numeric ('       ,./&lt;&gt;?aaa aa      !@#$%^&*()_+| ');

drop function clean_numeric (int4);
CREATE FUNCTION  clean_numeric (int4) RETURNS int4 AS '
  my $Text = shift;
  $Text =~ s/[^0-9]//gi;
  return $Text;
' LANGUAGE 'plperl';
 -- Just do show you what this function cleans up.
select clean_numeric (1111);



</pre>

<p>
After you save the perl script, execute "chmod 755 Create_Functions.pl"
and then "./Create_Functions.pl". That should do it. 
<p>
If you have installed PostgreSQL and Perl correctly, and you have setup
the database and your account has permissions to that database, then everything
should have worked fine.  

<h3><a NAME="consider"></a>Considerations to explore.</h3>
I would like to test TCL, Python, and other languages as well for
stored procedures. If you are using MySQL, and I don't believe it has
stored procedures, you may want to consider PostgreSQL if you like the
style I mentioned. A nice GUI application to create tables and 
make changes to tables would be nice. Lastly, examples of how to
connect to the database server to use these stored procedures (using Perl, 
Python, PHP, TCL, C, etc) would be nice.  

<h3><a NAME="Conclusion"></a>Conclusion</h3>
The combination of PostgreSQL and Perl rocks. I can use Perl for three things, 
stored procedures, to setup my database, and to make Perl modules for
Apache that connect to the PostgreSQL database. Similar stuff can be
accomplished with other programming languages like Python, TCL, and others.
I want to try Python at some point when it gets out of beta
for PostgreSQL.
<p>
All database servers should use procedures exclusively for changing data. 
You could even argue that you should make custom stored procedures
for selecting data as well. The reason why this is so important is because
the web programmer (or other type of programmer) doesn't have to know 
anything about how to manipulate the data. They just submit variables
to procedures. This lets the web programmer use any programming language
he/she wants to without changing the behaviour of the database. The database
and how you use it becomes abstract. 
<p>
One stupid thing my perl script does is execute the custom sql code
for each table. This s very bad. I will have to go back and fix it later. 
You may want to test my stuff out with these commands:
<pre>
select sql_account_insert();
select sql_account_delete(1);
select sql_account_insert();
select sql_account_update(2,'mark','nielsen');
select sql_account_purge();
select sql_account_unpurge();
select * from account_backup;
select sql_account_delete(2);
select sql_account_insert();
select sql_account_update(1,'john','nielsen');
select sql_account_purge();
select * from account_backup;
</pre> 

<h3>
<a NAME="REF"></a>References</h3>

<ol>
<li><a href="../issue67/nielsen.html">
My Previous PostgreSQL article</a>.
<li>
If this article
changes, it will be available at
<a href="http://www.gnujobs.com/Articles/22/Perl_PostgreSQL2.html">
http://www.gnujobs.com/Articles/22/Perl_PostgreSQL2.html</a></li>
</ol>







<!-- *** BEGIN bio *** -->
<SPACER TYPE="vertical" SIZE="30">
<p> 
<h4><img align=bottom alt="" src="../gx/note.gif">Mark Nielsen</h4>
<EM>Mark works as an independent consultant donating time to causes like
GNUJobs.com, writing articles, writing free software, and working
as a volunteer at <a href="http://www.eastmont.net">eastmont.net</a>.</EM>

<!-- *** END bio *** -->

<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P --> 
<H5 ALIGN=center>

Copyright &copy; 2001, Mark Nielsen.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR> 
Published in Issue 69 of <i>Linux Gazette</i>, August 2001</H5>
<!-- *** END copyright *** -->


<H4 ALIGN="center">
"Linux Gazette...<I>making Linux just a little more fun!</I>"
</H4>

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

<center>
<H1><font color="maroon">Learning Perl, part 5</font></H1>
<H4>By <a href="mailto:ben-fuzzybear@yahoo.com">Ben Okopnik</a></H4>
</center>
<P> <HR> <P>  

<!-- END header -->




<br><tt>What is the sound of Perl? Is it not the sound of a wall that people
have stopped banging their heads against?</tt>
<br><tt>&nbsp;-- Larry Wall</tt>

<p><b>Overview</b>
<p>This month, we're going to cover some general Perl issues, look at a
way to use it in Real Life(tm), and take a quick look at a mechanism that
lets you leverage the power of O.P.C. - Other People's Code :). <i>Modules</i>
let you plug chunks of pre-written code into your own scripts, saving you
hours - or even days - of programming. That will wrap up this introductory
series, hopefully leaving you with enough of an idea of what Perl is to
write some basic scripts, and perhaps a desire to explore further.
<br>&nbsp;
<p><b>A Quick Correction</b>
<p>One of our readers, A. N. Onymous (he didn't want to give me his name;
I guess he decided that fame wasn't for him...), wrote in regarding a statement
that I made in last month's article - that "close" without any parameters
closes <i>all</i> filehandles. After cranking out a bit of sample code
and reading the docs a bit more closely, I found that he was right: it
only closes the currently selected filehandle (<tt>STDOUT</tt> by default).
Thanks very much - well spotted!
<br>&nbsp;
<p><b>Excercises</b>
<p>In the last article, I suggested a couple of script ideas that would
give you some practice in using what you'd learned previously. One of the
people who sent in a script was Tjabo Kloppenburg; a brave man. :) No worries,
Tjabo; either you did a good job, or you get to learn a few things... it's
a win-win situation.
<p>The idea was to write a script that read "/etc/services", counted UDP
and TCP ports, and wrote them out to separate files. Here was Tjabo's solution
(my comments are preceded with a '###'):
<br>
<hr WIDTH="100%"><tt>#!/usr/bin/perl -w</tt>
<br><tt>### Well done; let the computer debug your script!</tt>
<p><tt>$udp = $tcp = 0;</tt>
<br><tt>### Unnecessary: Perl does not require variable declaration.</tt>
<p><tt># open target files:</tt>
<br><tt>open (TCP, ">>tcp.txt") or die "Arghh #1 !";</tt>
<br><tt>open (UDP, ">>udp.txt") or die "Arghh #2 !";</tt>
<p><tt>### My fault here: in a previous article, I showed a quick hack
in which</tt>
<br><tt>### I used similar wording for the "die" string. Here is the proper
way</tt>
<br><tt>### to use it:</tt>
<br><tt>###</tt>
<br><tt>### open TCP, ">tcp.txt" or die "Can't open tcp.txt: $!\n";</tt>
<br><tt>###</tt>
<br><tt>### The '$!' variable gives the error returned by the system, and
should</tt>
<br><tt>### definitely be used; the "\n" at the end of the "die" string
prevents</tt>
<br><tt>### the error line number from being printed. Also, the ">>" (append)</tt>
<br><tt>### modifier is inappropriate: this will cause anything more than
one</tt>
<br><tt>### execution of the script to append (rather than overwrite) the</tt>
<br><tt>### contents of those files.</tt>
<p><tt># open data source:</tt>
<br><tt>open (SERV, "&lt;/etc/services") or die "Arghh #3 !";</tt>
<p><tt>while( &lt;SERV> ) {</tt>
<br><tt>&nbsp; if (/^ *([^# ]+) +(\d+)\/([tcpud]+)/) {</tt>
<p><tt>### The above regex has several problems, some of them minor</tt>
<br><tt>### (unnecessary elements) and one of them critical: it actually
misses</tt>
<br><tt>### out on most of the lines in "/etc/services". The killer is
the ' +'</tt>
<br><tt>### that follows the first capture: "/etc/services" uses a mix
of spaces</tt>
<br><tt>### and *tabs* to separate its elements.</tt>
<p><tt>&nbsp;&nbsp;&nbsp; $name&nbsp;&nbsp; = $1;</tt>
<br><tt>&nbsp;&nbsp;&nbsp; $port&nbsp;&nbsp; = $2;</tt>
<br><tt>&nbsp;&nbsp;&nbsp; $tcpudp = $3;</tt>
<br><tt>&nbsp;&nbsp;&nbsp; $tmp = "$name ($port)\n";</tt>
<p><tt>### The above assignments are unnecessary; $1, $2, etc. will keep
their</tt>
<br><tt>### values until the next succesful match. Removing all of the
above</tt>
<br><tt>### and rewriting the "if" statement below as</tt>
<br><tt>###</tt>
<br><tt>### if ( $3 eq "udp" ) { print UDP "$1 ($2)\n"; $udp++; }</tt>
<br><tt>###</tt>
<br><tt>### would work just fine.</tt>
<p><tt>&nbsp;&nbsp;&nbsp; if ($tcpudp eq "udp") {</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; print UDP $tmp;</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; $udp++;</tt>
<br><tt>&nbsp;&nbsp;&nbsp; }</tt>
<p><tt>&nbsp;&nbsp;&nbsp; if ($tcpudp eq "tcp") {</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; print TCP $tmp;</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; $tcp++;</tt>
<br><tt>&nbsp;&nbsp;&nbsp; }</tt>
<br><tt>&nbsp; }</tt>
<br><tt>}</tt>
<p><tt># just learned :-) :</tt>
<br><tt>for ( qw/SERV TCP UDP/ ) { close $_ or die "can't close $_: $!\n";
}</tt>
<p><tt>print "TCP: $tcp, UDP: $udp\n";</tt>
<br>
<hr WIDTH="100%">
<p>The above script counted 14 TCPs and 11 UDPs in my "/etc/services" (which
actually contains 185 of one and 134 of the other). Let's see if we can
improve it a bit:
<br>
<hr WIDTH="100%">
<br><tt>#!/usr/bin/perl -w</tt>
<p><tt>open SRV, "&lt;/etc/services" or die "Can't read /etc/services:
$!\n";</tt>
<br><tt>open TCP, ">tcp.txt"&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; or die
"Can't write tcp.txt: $!\n";</tt>
<br><tt>open UDP, ">udp.txt"&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; or die
"Can't write udp.txt: $!\n";</tt>
<p><tt>for ( &lt;SRV> ) {</tt>
<br><tt>&nbsp;&nbsp;&nbsp; if ( s=^([^# ]+)(\s+\d+)/tcp.*$=$1$2= ) { print
TCP; $tcp++; }</tt>
<br><tt>&nbsp;&nbsp;&nbsp; if ( s=^([^# ]+)(\s+\d+)/udp.*$=$1$2= ) { print
UDP; $udp++; }</tt>
<br><tt>}</tt>
<p><tt>close $_ or die "Failed to close $_: $!\n" for qw/SRV TCP UDP/;</tt>
<p><tt>print "TCP: $tcp\t\tUDP: $udp\n";</tt>
<br>
<hr WIDTH="100%">
<br>In the "for" loop, where all the 'real' work is done, I perform the
following matches/substitutions:
<p><i>Starting at the beginning of the line, (begin capture into $1) match
any character that is not a '#' or a space and occurs one or more times
(end capture). (Begin capture into $2) Match any whitespace character that
occurs one or more times that is followed by one or more digits (end capture),
a forward slash, and the string 'tcp' followed by any</i>
<br><i>number of any character to the end of the line. Replace the matched
string (i.e., the entire line) with $1$2 (which contain the name of the
service, whitespace, and the port number.) Write the result to the TCP
filehandle, and increment the "$tcp" variable.</i>
<p><i>Repeat for 'udp'.</i>
<p>Note that I used the '=' symbol for the delimiter in the 's///' function.
'=' has no particular magic about it; it's just that I was trying to avoid
conflict with the '/' and the '#' characters which appear as part of the
regex (those being two commonly used delimiters), and there was a sale
on '=' at the neighborhood market. :) Any other character or symbol would
have done as well.
<br>&nbsp;
<p>Here are a couple of simple solutions for the other two problems:
<p>1. Open two files and exchange their contents.
<br>
<hr WIDTH="100%">
<br><tt>#!/usr/bin/perl -w</tt>
<br><tt># The files whose contents are to be exchanged are named "a" and
"b".</tt>
<p><tt>for ( A, B ) { open $_, "&lt;\l$_" or die "Can't open \l$_: $!\n";
}</tt>
<br><tt>@a = &lt;A>; @b = &lt;B>;</tt>
<p><tt>for ( A, B ) { open $_, ">\l$_" or die "Can't open \l$_: $!\n";
}</tt>
<br><tt>print A @b; print B @a;</tt>
<br>
<hr WIDTH="100%">
<br>Pretty conservative, basic stuff. A minor hack: I used the '\l' modifier
to set the filename to lowercase. Note that re-opening a filehandle closes
it automatically - you don't have to close a handle between different "open"s.
Also, explicitly closing a file isn't always necessary: Perl will close
the handles for you on script exit (but be aware that some OSs have been
reported as leaving them open.) By the way, the current version of Perl
(5.6.1) has a neat mechanism that helps you do what I did above, but far
more gracefully:
<br>
<hr WIDTH="100%">
<br><tt>...</tt>
<br><tt>$FN = "/usr/X11R6/include/X11/Composite.h";</tt>
<br><tt>open FN or die "I choked on $FN: $!\n";</tt>
<br><tt># "FN" is now open as a filehandle to "Composite.h".</tt>
<br><tt>...</tt>
<br>
<hr WIDTH="100%">
<br>All the distros with which I'm familiar currently come with Perl version
5.005.003 installed. I suggest getting 5.6.1 from CPAN (see below) and
installing it; different versions of Perl coexist quite happily on the
same machine. (Note that <b>replacing</b> an installed version by anything
other than a distro package can be rather tricky, given how much system
stuff depends on
<br>Perl.)
<p>I'm sure that a number of folks figured out that renaming the files
would produce the same result. That wasn't the point of the excercise...
but here's a fun way to do that:
<br>
<hr WIDTH="100%">
<br><tt>#!/usr/bin/perl -w</tt>
<br><tt>%h = qw/a $$.$$ b a $$.$$ b/;</tt>
<br><tt>rename $x, $y while ($x, $y) = each %h</tt>
<br>
<hr WIDTH="100%">
<br>Here, I created a hash using a list of the filenames and a temporary
variable - "$$" in Perl, just as in the shell, is the current process ID,
and "$$.$$" is almost certainly a unique filename - and cycled through
it with the "each" command, which retrieves key/value pairs from hashes.
I suppose you could call it "round-robin renaming"...
<br>&nbsp;
<p>2. Read "/var/log/messages" and print out any line that contains the
words "fail", "terminated/terminating", or " no " in it. Make it case-insensitive.
<p>This one is an easy one-liner:
<br>
<hr WIDTH="100%">
<br><tt>perl -wne 'print if /(fail|terminat(ed|ing)| no )/i' /var/log/messages</tt>
<br>
<hr WIDTH="100%">
<br>The interesting part there is the "alternation" mechanism in the match:
it allows strings like "<tt>(abc|def|ghi)</tt>" for lines matching any
of the above.
<br>&nbsp;
<p><b>Building Quick Tools</b>
<p>A few days ago, I needed to convert a text file into its equivalent
in phonetic alphabet - a somewhat odd requirement. There may or may not
have been a program to do this, but I figured I could write my own in
<br>less time that it would take me to find one:
<p>1) I grabbed a copy of the phonetic alphabet from the Web and saved
it to a file. I called the file "phon", and it loked like this:
<p><tt>Alpha</tt>
<br><tt>Bravo</tt>
<br><tt>Charlie</tt>
<br><tt>Delta</tt>
<br><tt>Echo</tt>
<br><tt>Foxtrot</tt>
<br><tt>Golf</tt>
<br><tt>...</tt>
<p>2) Then, I issued the following command:
<br>
<hr WIDTH="100%">
<br><tt>perl -i -wple's/^(.)(.*)$/\t"\l$1" => "$1$2",/' phon</tt>
<br>
<hr WIDTH="100%">
<br>Ta-daa! Magic. (See below for a breakdown of the substitute operation.)
The file now looked like this:
<p><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "a" => "Alpha",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "b" => "Bravo",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "c" => "Charlie",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "d" => "Delta",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "e" => "Echo",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "f" => "Foxtrot",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "g" => "Golf",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; ...</tt>
<p>3) A few seconds later, I had the tool that I needed - a script with
exactly one function and one data structure in it:
<br>
<hr WIDTH="100%">
<br><tt>#!/usr/bin/perl -wlp</tt>
<br><tt># Created by Benjamin Okopnik on Sun May 27</tt>
<br><tt>13:07:49 2001</tt>
<p><tt>s/([a-zA-Z])/$ph{"\l$1"} /g;</tt>
<p><tt>BEGIN {</tt>
<br><tt>&nbsp;&nbsp;&nbsp; %ph = (</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "a" => "Alpha",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "b" => "Bravo",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "c" => "Charlie",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "d" => "Delta",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "e" => "Echo",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "f" => "Foxtrot",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "g" => "Golf",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "h" => "Hotel",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "i" => "India",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "j" => "Juliet",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "k" => "Kilo",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "l" => "Lima",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "m" => "Mike",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "n" => "November",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "o" => "Oscar",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "p" => "Papa",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "q" => "Quebec",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "r" => "Romeo",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "s" => "Sierra",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "t" => "Tango",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "u" => "Uniform",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "v" => "Victor",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "w" => "Whisky",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "x" => "X-ray",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "y" => "Yankee",</tt>
<br><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; "z" => "Zulu",</tt>
<br><tt>&nbsp;&nbsp;&nbsp; );</tt>
<br><tt>}</tt>
<br>
<hr WIDTH="100%">
<br>The above script will accept either keyboard input or a file as a command-line
argument, and return the phonetic alphabet equivalent of the text.
<p>This is one of the most common ways I use Perl - building quick tools
that I need to do a specific job. Other people may have other uses for
it - after all, <a href="#1">TMTOWTDI [1]</a> - but for me, a computer
without Perl is only half-useable. To drive the point even further home,
a group of Perl Wizards have rewritten most of the system utilities in
Perl - take a look at &lt;http://language.perl.com/ppt/> - and have fixed
a number of annoying quirks in the process. As I understand it, they were
motivated by the three chief virtues of the programmer: Laziness, Impatience,
and
<br>Hubris (if that confuses you, see the Camel Book ["Programming Perl,
Third Edition"] for the explanation). If you want to see <b>well</b>-written
Perl code, there are very few better places. Do note that the project is
not yet complete, but a number of Unices are already catching on: Solaris
8 has a large number of Perl scripts as part of the system
<br>executables, and doing a
<p><tt>file /sbin/* /usr/bin/* /usr/sbin/*|grep -c perl</tt>
<p>shows at least the Debian "potato" distro as having 82 Perl scripts
in the above directories.
<br>&nbsp;
<p>OK, now for the explanation of the two s///'s above. First, the "magic"
converter:
<p><tt>perl -i -wple's/^(.)(.*)$/\t"\l$1" => "$1$2",/' phon</tt>
<p>The "-i", "-w", "-p", and "-e" switches were described in the second
part of this series; as a quick overview, this will edit the contents of
the file by looping through it and acting on each line. The Perl "warn"
mechanism is enabled, and the script to be executed runs from the command
line. The "-l" enables end-of-line processing, in effect adding a carriage
return to the lines that don't have it. The substitution regex goes like
this:
<p><i>Starting at the beginning of the line, (begin capture into $1) match
one character (end capture, begin capture into $2). Capture any number
of any character (end capture) to the end of the line.</i>
<p>The replacement string goes like this:
<p><i>Print a tab, followed by the contents of $1 in lowercase* and surrounded
by double quotes. Print a space, the '=>' digraph, another space, $1$2
surrounded by double quotes and followed by a comma.</i>
<p>* This is done by the "\l" 'lowercase next character' operator (see
'Quote and Quote-like Operators' in the "perlop" page.)
<br>&nbsp;
<p>The second one is also worth studying, since it points up an interesting
feature - that of using a hash value (including modifying the key "on the
fly") in a substitution, a very useful method:
<p><tt>s/([a-zA-Z])/$ph{"\l$1"} /g;</tt>
<p>First, the regex:
<p><i>(Begin capture into $1) Match any character in the 'a-zA-Z' range
(end capture).</i>
<p>Second, the replacement string:
<p><i>Return a value from the "%ph" hash by using the lowercase version
of the contents of $1 as the key, followed by a space.</i>
<br>&nbsp;
<p>The BEGIN { ... } block makes populating the hash a one-time event,
despite the fact that the script may loop thousands of times. The mechanism
here is the same as in Awk, and was mentioned in the previous article.
So, all we do is use every character as a key in the "%ph" hash, and print
out the value associated with that key.
<p>Hashes are very useful structures in Perl, and are well worth studying
and understanding.
<br>&nbsp;
<p><b>Modular Construction</b>
<p>One of the wonderful things about Perl - really, the thing that makes
it a living, growing language - is the community that has grown up around
it. A number of these folks have contributed useful chunks of code that
are made to be re-used; that, in fact, make Perl one of the most powerful
languages on the planet.
<p>Imagine a program that goes out on the Web, connects to a server, retrieves
the weather data - either the current or the forecast - for your city,
and prints the result to your screen. Now, imagine this entire Perl script
taking just <b>one</b> line.
<p><tt>perl -MGeo::WeatherNOAA -we 'print print_forecast( "Denver", "CO"
)'</tt>
<p>That's it. The whole thing. How is it possible?
<p>(Note that this will not work unless you have the 'Geo::WeatherNOAA'
module installed on your system.)
<p>The CPAN (Comprehensive Perl Archive Network) is your friend. :) If
you go to &lt;http://cpan.org/> and explore, you'll find lots and lots
(and LOTS) of modules designed to do almost every programming task you
could imagine. Do you want your Perl script converted to Klingon (or Morse
code)? Sure. Would you like to pull up your stock's performance from Deutsche
Bank Gruppe funds? Easy as pie. Care to send some SMS text messages? No
problem! With modules, these are short, easy tasks that can be coded in
literally seconds.
<p>The standard Perl distribution comes with a number of useful modules
(for short descriptions of what they do, see "Standard Modules" in 'perldoc
perlmodlib'); one of them is the CPAN module, which automates the module
downloading, unpacking, building, and installation process. To use it,
simply type
<p><tt>perl -MCPAN -eshell</tt>
<p>and follow the prompts. The manual process, which you should know about
just in case there's some complication, is described on the "How to install"
page at CPAN, &lt;http://http://cpan.org/modules/INSTALL.html>. I highly
recommend reading it. The difference between the two processes, by the
way, is exactly like that of using "apt" (Debian) or "rpm" (RedHat) and
trying to install a tarball by hand: 'CPAN' will get all the prerequisite
modules to support the one you've requested, and do all the tests and the
installation, while doing it manually can be rather painful. For specifics
of using the CPAN module - although the above syntax is the way you'll
use it 99.9% of the time - just type
<p><tt>perldoc CPAN</tt>
<p>The complete information for any module installed on your system can
be accessed the same way.
<p>As you've probably guessed by now, the "-M" command line switch tells
Perl to use the specified module. If we want to have that module in a script,
here's the syntax:
<br>
<hr WIDTH="100%">
<br><tt>#!/usr/bin/perl -w</tt>
<p><tt>use Finance::Quote;</tt>
<p><tt>$q = Finance::Quote->new;</tt>
<br><tt>my %stocks = $q->fetch("nyse","LNUX");</tt>
<br><tt>print "$k: $v\n" while ($k, $v) = each %stocks;</tt>
<br>
<hr WIDTH="100%">
<br>The above program (you'll need to install the "Finance::Quote" module
for it to work) tells me all about VA Linux on the New York Stock Exchange.
Not bad for five lines of code.
<p>The above is an example of the <i>object-oriented</i> style of module,
the type that's becoming very common. After telling Perl to use the module,
we create a new instance of an object from the "Finance::Quote" class and
assign it to <tt>$q</tt>. We then call the "fetch" method (the methods
are listed in the module's documentation) with the "nyse" and "LNUX" variables,
and print the results stored in the returned hash.
<p>A lot of modules are of the so-called <i>exporting</i> style; these
simply provide additional functions when "plugged in" to your program.
<br>
<hr WIDTH="100%">
<br><tt>#!/usr/bin/perl -w</tt>
<br><tt>use LWP::Simple;</tt>
<p><tt>$code = mirror( "http://slashdot.org", "slashdot.html" );</tt>
<br><tt>print "Slashdot returned a code of $code.\n";</tt>
<br>
<hr WIDTH="100%">
<br>In this case, "mirror" is a new function that came from the LWP::Simple
module. Somewhat obviously, it will copy ("mirror") a given web page to
a specified file, and return the code (e.g., '404' for 'RC_NOT_FOUND).
<br>&nbsp;
<p><b>Wrapping It Up</b>
<p>Well, that was a quick tour through a few interesting parts of Perl.
Hopefully, this has whetted a few folks' tastebuds for more, and has shown
some of its capabilities. If you're interested in extending your Perl knowledge,
here are some recommendations for reading material:
<p><b><font size=-1>Learning Perl, 3rd Edition (coming out in July)</font></b>
<br><font size=-1>Randal Schwartz and Tom Phoenix</font>
<p><b><font size=-1>Programming Perl, 3rd Edition</font></b>
<br><font size=-1>Larry Wall, Tom Christiansen &amp; Jon Orwant</font>
<p><b><font size=-1>Perl Coookbook</font></b>
<br><font size=-1>By Tom Christiansen &amp; Nathan Torkington</font>
<p><b><font size=-1>Data Munging with Perl</font></b>
<br><font size=-1>By David Cross</font>
<p><b><font size=-1>Mastering Algorithms with Perl</font></b>
<br><font size=-1>By Jon Orwant, Jarkko Hietaniemi &amp; John Macdonald</font>
<p><b><font size=-1>Mastering Regular Expressions</font></b>
<br><font size=-1>By Jeffrey E. F. Friedl</font>
<p><b><font size=-1>Elements of Programming with Perl</font></b>
<br><font size=-1>by Andrew Johnson</font>
<br>&nbsp;
<p>Good luck with your Perl programming - and happy Linuxing!
<br>&nbsp;
<p><b>Ben Okopnik</b>
<br><tt>perl -we'print reverse split//,"rekcah lreP rehtona tsuJ"'</tt>
<br>
<hr WIDTH="100%">
<br><a NAME="1"></a>1. "There's More Than One Way To Do It" - the motto
of Perl. I find it applicable to all of Unix, as well.
<p><tt>References:</tt>
<p><tt>Relevant Perl man pages (available on any pro-Perl-y configured</tt>
<br><tt>system):</tt>
<p><tt>perl&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; - overview&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
perlfaq&nbsp;&nbsp; - Perl FAQ</tt>
<br><tt>perltoc&nbsp;&nbsp; - doc TOC&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
perldata&nbsp; - data structures</tt>
<br><tt>perlsyn&nbsp;&nbsp; - syntax&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
perlop&nbsp;&nbsp;&nbsp; - operators/precedence</tt>
<br><tt>perlrun&nbsp;&nbsp; - execution&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
perlfunc&nbsp; - builtin functions</tt>
<br><tt>perltrap&nbsp; - traps for the unwary&nbsp; perlstyle - style guide</tt>
<p><tt>"perldoc", "perldoc -q" and "perldoc -f"</tt>




<!-- *** BEGIN bio *** -->
<SPACER TYPE="vertical" SIZE="30">
<P> 
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Ben Okopnik</H4>
<EM>A cyberjack-of-all-trades, Ben wanders the world in his 38' sailboat, building
networks and hacking on hardware and software whenever he runs out of cruising
money. He's been playing and working with computers since the Elder Days
(anybody remember the Elf II?), and isn't about to stop any time soon.</EM>


<!-- *** END bio *** -->

<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P --> 
<H5 ALIGN=center>

Copyright &copy; 2001, Ben Okopnik.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR> 
Published in Issue 69 of <i>Linux Gazette</i>, August 2001</H5>
<!-- *** END copyright *** -->


<H4 ALIGN="center">
"Linux Gazette...<I>making Linux just a little more fun!</I>"
</H4>

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

<center>
<H1><font color="maroon">DMCA in the news: Russian programmer arrested, nerds protest for his release</font></H1>
<H4>By <a href="mailto:gazette@ssc.com">Mike Orr</a></H4>
</center>
<P> <HR> <P>  

<!-- END header -->




<P> The Digital Millennium Copyright Act (DMCA) has claimed its 
first  prisoner.  Russian programmer Dmitry Sklyarov was arrested by the FBI
July 16 after giving a talk at DEF CON in Las Vegas, Nevada, on the inadequate
security of Adobe's eBook format.  But he was arrested not because of the
talk, but because his company
ElcomSoft sold (and he worked on) a product that converted said eBook
format to ordinary PDF.  This violates the DMCA's circumvention
provision, which  prohibits circumventing any encryption that serves as a form
of copy protection. Never mind that the program was built and sold in  Russia,
which has no such law.  (Neither do Canada or Europe, at least not yet.) Never
mind that there are legitimate uses for ElcomSoft's product, such as exercising
your Fair Use rights or having a speech synthesizer read you the book if you
are blind.  

<P> Protests erupted a week later in several US cities, asking for
the release of Dmitry, boycotting Adobe, and/or arguing for the repeal of the
DMCA.  The Electronic Frontier Foundation (EFF) talked with Adobe and
got them to withdraw their complaint against Dmitry and ask for his 
release.  However, Dmitry is still in an Oklahoma jail without bail, and
his fate rests with the US justice department and a court trial.
A second route of protests took place a week later (July 30) to convince
the Justice Department to release Dmitry and to convince Congress to repeal
the DMCA.  There are other problems with the DMCA too. (Remember DeCSS?
What about your previous right to reverse engineer?)  

<P> The DMCA is an important issue for all Americans, even those who aren't
engineers or are computer novices, because the laws are changing much
faster than people realize, and you may find that rights you've always had
no longer exist, and that your right to read what you want when you want
(without some company keeping track of you)--and to criticize what you
read--may be gone.

<P> It's also an important issue to those outside the US.  Canada is 
already debating a similar law.  And Europeans must also be wary, lest
corporate lobbyists sneak it past your parliaments when you're not watching.
Already, American engineers have started sending their resumes to Canada
and Europe, in case their jobs get declared illegal over here.

<P> So much has been written about Sklyarov and the DMCA that I won't
retell it all but just point to some existing links.

<UL>
<LI> <A HREF="http://www.nytimes.com/2001/07/30/opinion/30LESS.html">Jail Time in the Digital Age</A> (Excellent New York Times article that articulates
many of the issues.  Free for one week, then purchase online or go to the
library and choose the July 30, 2001 edition.)
<LI> <A HREF="http://search.nytimes.com:80/plweb-cgi/fastweb?state_id=996644093&view=site&docrank=2&numhitsfound=5&query=%28sklyarov%29%20AND%20%2820010703%3C%3Dpdate%29&query_rule=%28$query%29&query1=thedbs%3Dpast30days%26section%3DALL%26fields%3DALL%26thequery%3Dsklyarov&query2=sorting%3DBYFIELD%3A-skey_pdate&query7=sklyarov&query8=from%20the%20past%2030%20days&docid=58838&docdb=2001arc&dbname=unify&numresults=10&sorting=BYFIELD%3A-skey_pdate&operator=AND&TemplateName=abs_MPoff.tmpl&setCookie=1">Arrest Raises Stakes in Battle Over Copyright</A>
(Another excellent NY Times article that also explains some of the issues.
Purchase online or go to the library and look at the July 23, 2001 edition.)
<LI> <A HREF="http://www.wired.com/">Wired</A> and
<A HREF="http://www.theregister.co.uk">The Register</A> (UK) have had several
articles.
<LI> <A HREF="http://noframes.linuxjournal.com/articles/misc/0048.html">We're Not Your Enemies; We're Your Customers</A> (Yours Truly wrote a 
<I>Linux Journal</I> web article on the Seattle protest July 24, on the 
effect of the DMCA on programmers, and some ideas for what to do now)

<LI> <A HREF="http://nodmca.org">nodmca.org</A> 
<LI> <A HREF="http://www.freesklyarov.org">www.freesklyarov.org</A>
<LI> <A HREF="http://www.anti-dmca.org/">http://www.anti-dmca.org/</A>
<LI> <A HREF="http://www.eff.org/">Electronic Frontier Foundation (EFF)</A>
<LI> <A HREF="http://www.eff.org/Legal/Cases/Felten_v_RIAA/20010606_eff_felten_pr.html">Felten vs RIAA</A>
<LI> <A HREF="http://www.gnu.org/philosophy/right-to-read.html">The Right to Read</A>
(a dysotopian short story by Richard Stallman, 1997)
<LI> <a href="http://lwn.net/2001/0719/">Linux Weekly News editorial</a> (scroll
down to "DMCA")
<LI> <A HREF="http://www.freedmitry.org">www.freedmitry.org</A>
<LI> <A HREF="http://www.boycottadobe.org">www.boycottadobe.org</A> (has some
technical references about the eBook case)
</UL>





<!-- *** BEGIN bio *** -->
<SPACER TYPE="vertical" SIZE="30">
<P>
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Mike Orr</H4>
<EM>Mike ("Iron") is the Editor of <I>Linux Gazette</I>.  You can read what he
has to say in the Back Page column in this issue.  He has been a Linux
enthusiast since 1991 and a Debian user since 1995.  He is SSC's web technical
coordinator, which means he gets to write a lot of Python scripts.
Non-computer interests include Ska/Oi! music and the international language
Esperanto.  The nickname Iron was given to him in college--short for Iron Orr,
hahaha.</EM>

<!-- *** END bio *** -->

<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P --> 
<H5 ALIGN=center>

Copyright &copy; 2001, Mike Orr.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR> 
Published in Issue 69 of <i>Linux Gazette</i>, August 2001</H5>
<!-- *** END copyright *** -->


<H4 ALIGN="center">
"Linux Gazette...<I>making Linux just a little more fun!</I>"
</H4>

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

<center>
<H1><font color="maroon">Installing Tomcat on Linux</font></H1>
<H4>By <a href="mailto:tl082@yahoo.com">Allan Peda</a></H4>
</center>
<P> <HR> <P>  

<!-- END header -->




<img src="misc/peda/tomcat.png" 
  alt="Screencap of the Tomcat Demo Webserver Running" 
  WIDTH="130" HEIGHT="92" ALIGN="left">

By now I'm sure many of you my have the impression that unless you know
Java, your r&eacute;sum&eacute; is severely handicapped, and even if
you are fluent in Java, increasingly employers will ask if you know Java
Server Pages (JSPs), and/or servlets.  Fortunately, there is a free
application server for Java Server Pages, and the related Java
Servlets, it is called called Jakarta-Tomcat (hereafter referred to
simply as Tomcat). I decided to download and install it, documenting
my experiences for reference.  I set up  Tomcat on a vintage Pentium
2/200 running SuSE 7.2, however it appears that the steps described
here should work with any recent distribution, as long as Java can
compile the source.  
<p>

Installation of the applet server involves the downloading and
compilation of several packages in addition to the obvious need for
Java and Tomcat.  The following packages are necessary:
<p>
<table CLASS="listing">
<caption>Required Packages to Set Up Jakarta-Tomcat</caption>
<tr><th>Package</th><th>Source  &nbsp;</th></tr>
<tr><td>Java SDK 1.3.1          &nbsp;</td>
         <td><a href="#java_download">Sun</a> &nbsp;</td></tr>
<tr><td>XML Parser Library 1.1  &nbsp;</td>
         <td><a href="#java_xml">Sun</a> &nbsp;</td></tr>
<tr><td>Secure Sockets for Java 1.0.2 &nbsp;</td>
         <td><a href="#java_sse">Sun</a> &nbsp;</td></tr>
<tr><td>Java Servlet API 3.2.3  &nbsp;</td>
         <td><a href="#jakarta_download">Apache Foundation</a> &nbsp;</td> </tr>
<tr><td>Jakarta Ant 1.3         &nbsp;</td>
         <td><a href="#jakarta_download">Apache Foundation</a> &nbsp;</td> </tr>
<tr><td>Jakarta Tomcat 3.2.3    &nbsp;</td>
         <td><a href="#jakarta_download">Apache Foundation</a> &nbsp;</td> </tr>
</table><p>

<p>
<h2>Getting Java Installed</h2><p>
Installation of Java has been written up so frequently it's almost
not worth repeating here, however for completeness I'll quickly run through the
steps using RPM.  I downloaded version 1.3 of the SDK (also known as
the JDK) from the <a href="#java_download">Java web site</a>, 
but 1.4 is in Beta, and may be out by the time you read this. The
notes for the Secure Sockets library indicate that 1.4 will include
them, so the installation will be simplified somewhat.
<p>

For Linux, Sun's Java comes as a script wrapped around an RPM package,
so that you must execute it and agree to the licensing before you get
to actually install the RPM.&nbsp; After unpacking the shell script to
yield an RPM, follow the standard installation as root.

<p>
<table CLASS="sourcecode">
<caption>RPM install for Java (after unpacking)</caption>
<tr><td>
    <pre>

    moby:~ &gt; sudo rpm -Uv jdk-1.3.1.i386.rpm
    </pre>
</td></tr>
</table>
<p>

I modified my path to include the location of the JDK, on SuSE you are
advised to edit /etc/profile.local to accomplish this, although on
other distributions one might edit /etc/profile directly. Note also the
environmental variable for $JAKARTA_HOME, and $TOMCAT_HOME, we can
ignore them for now, but you will need them soon enough as part of the
installation procedure, so it's easier to set them now. Note that I
did not initially set CLASSPATH, although you may want or need to.
You'll see below the steps I took to make sure that Java could find
the libraries. 

<p>
<table CLASS="sourcecode"  WIDTH="100%">
<caption>Environmental Variables Needed</caption>
<tr><td>
    <pre>

    #!/bin/bash
    JAVA_HOME=/usr/java/jdk1.3.1
    JAKARTA_HOME=/opt/jakarta
    ANT_HOME=$JAKARTA_HOME/jakarta-ant
    TOMCAT_HOME=$JAKARTA_HOME/build/tomcat
    PATH=$JAVA_HOME/bin:$PATH

    export JAVA_HOME JAKARTA_HOME ANT_HOME PATH TOMCAT_HOME
    </pre>
</td></tr>
</table>
<p>
<h2>Installing the Java XML Parser Library</h2>
I installed the libraries for XML parsing by unzipping and copying the
required libs to the library extensions directory (as root).  I
originally unzipped this file into my home directory.  Where the files
are initially unzipped doesn't matter, as long as java can find the
installed libraries.<p> 

<table CLASS="sourcecode"  WIDTH="100%">
<caption>Copying the XML Parser Library jar files</caption>
<tr><td>
    <pre>

    unzip jaxp-1_1.zip; cd jaxp-1.1
    moby:~/jaxp-1.1 > sudo cp *.jar $JAVA_HOME/jre/lib/ext
    </pre>
</td></tr>
</table>

<p>
Now, I like to do things step by step, so to check that your setup is 
able to find these new libraries, I suggest running an example
program, which is included in the XML parser library.
<br>
If your Java Virtual Machine (JVM) cannot find the libraries, you will
get an error like this:
<p>
<table CLASS="errormsg">
<caption>Error Message</caption>
<tr><td>
    <pre>

    moby:~/jaxp-1.1/examples/trax &gt; java Examples
    Exception in thread "main" java.lang.NoClassDefFoundError: 
    javax/xml/transform/TransformerException
    </pre>
</td></tr>
</table>
<p>

If you see something like this, check the library locations (.jar
files).  I constantly ran into this problem, and I solved it by
copying symlinking them to the correct location, or modifying
$CLASSPATH. 

<h2>Installing the Secure Sockets Library</h2>
<p>You follow a similar procedure to install the Secure
Sockets library copying the .jar libraries into the extensions directory.
<p>

<table CLASS="sourcecode">
<caption>Secure Sockets Library</caption>
<tr><td>
    <pre>

    moby:~/jsse1.0.2/lib &gt; sudo cp *.jar $JAVA_HOME/jre/lib/ext
    </pre>
</td></tr>
</table>
<p>
I then edited the file
/usr/java/jdk1.3.1/jre/lib/security/java.security to contain an entry
for "com.sun.net.ssl.internal.www.protocol" which was not in the
default file.
<p>
<table CLASS="sourcecode">
<caption>Java Security Entry for SSL</caption>
<tr><td>
    <pre>

    security.provider.1=sun.security.provider.Sun
    security.provider.2=com.sun.net.ssl.internal.ssl.Provider
    security.provider.3=com.sun.rsajca.Provider
    </pre>
</td></tr>
</table>
<p>

Now, to test that javac could find these libs, I quickly typed up
compiled the following piece of code, saved it as TestSSL.java and
compiled it:
<p>
<table CLASS="sourcecode">
<caption>Testing Secure Sockets</caption>
<tr><td>
    <pre>

    import javax.net.ssl.*;
    
    public class TestSSL {
	public static
	    void main(String [] arstring) {
	    try  {
		new java.net.URL("https://" + arstring[0] + "/").getContent();
	    } catch (Exception exception) {
		exception.printStackTrace();
	    }
	}
    }
    </pre>
</td></tr>
</table>
<p>
We compile to bytecode Using the standard javac invocation:
<pre>
      moby:~/jsse1.0.2 &gt; javac TestSSL.java
</pre>
Once again, if java could not find the libray, then I would get a
java.lang.NoClassDefFoundError error, and the code would not compile
to yield the TestSSL.class bytecode file.<p>

After compiling with javac to bytecode, I wanted to test the ssl library by
connecting to an SSL site (sourceforge).  Here it is necessary to 
specify the use of SSL on the command line, or as Sun's install docs say,
"add the handler's implementation package name to the list of packages
which are searched by the Java URL class".  I think of this as
analogous to linking the math library  using -lm as a linker option
to gcc, except it's done at runtime.

<table CLASS="sourcecode">
<caption>Explicitly Specifying the Handler</caption>
<tr><td>
    <pre>
    
    moby:~/jsse1.0.2 &gt; java \
    -Djava.protocol.handler.pkgs=com.sun.net.ssl.internal.www.protocol \
    TestSSL sourceforge.net
    moby:~/jsse1.0.2 &gt; echo $?
    moby:~/jsse1.0.2 &gt; 0
    </pre>
</td></tr>
</table>
<p>
<br>	
As an aside, if I did not include this argument to the JVM, I would
get the following error:<p>

<table CLASS="errormsg">
<caption>Unknown Protocol Error Message</caption>
<tr><td>
    <pre>

    moby:~/jsse1.0.2 &gt; java TestSSL sourceforge.net
    java.net.MalformedURLException: unknown protocol: https
	    at java.net.URL.&lt;init&gt;(URL.java:480)
	    at java.net.URL.&lt;init&gt;(URL.java:376)
	    at java.net.URL.&lt;init&gt;(URL.java:330)
	    at TestSSL.main(TestSSL.java:8)
    </pre>
</td></tr>
</table>
<p>

So now we have Apache, Java, Java libraries for XML and Secure
Sockets, and we can install Jakarta-Tomcat.  Not quite yet, we
still need Ant, a Java "make" replacement, and the Servlet API.

<h2>Installing Ant</h2>

Despite the fact that we not quite ready to install the Jakarta-Tomcat
distribution, the next step does involve installing some essential
components of Jakarta, so we need to modify our environment to
accommodate the package. We do this by creating the environmental variable 
$JAKARTA_HOME which was briefly introduced with the $JAVA_HOME
variable.  I decided to put Jakarta under /opt, simply because
there was space there, and also I try to put anything I build under
/opt, leaving /usr and /usr/local for the distribution RPM to
decide. Now we are getting to First, think of a place where you want
to install Ant.<p>

First download and unpack it.  In my example I downloaded the
compressed source into my home directory, then changed to the 
$JAKARTA_HOME directory.  I then unpacked it into the $JAKARTA_HOME
directory, letting tar choose the directory name.<p>

In order to comply with the requirement that jakarta-ant be in a
directory called $JAKARTA_HOME/jakarta-ant I symlinked the build
directory to the correct directory name. Then I cd'd into the
jakarta-ant/ directory and ran the bootstrap.sh script as root. 
After you run this script, there should be a new build/lib/
subdirectory containing the libraries just built:

<p>
<table CLASS="sourcecode">
<caption>Building Jakarta - Ant</caption>
<tr><td>
    <pre>

    moby:~ &gt; cd $JAKARTA_HOME
    moby:~/opt/jakarta&gt; tar xzf ~/jakarta-ant-1.3-src.tar.gz
    moby:/opt/jakarta &gt; sudo ln -s jakarta-ant-1.3/ jakarta-ant
    moby:~/opt/jakarta &gt; cd jakarta-ant
    moby:/opt/jakarta/jakarta-ant &gt; sudo sh bootstrap.sh    
    moby:/opt/jakarta/jakarta-ant > ls -1 build/lib/
    ant.jar
    optional.jar
    </pre>
</td></tr>
</table>
<p>

<a href="misc/peda/bootstrap_ant.txt">Output of the Ant bootstrap
script</a><p>

<h2>Installing the Servlet API</h2>
Next we install the servlet API, once again symlinking the real
extract directory to the required directory name:

<p>
<table CLASS="sourcecode">
<caption>Building the Servlet API</caption>
<tr><td>
    <pre>

    moby:/opt/jakarta &gt; sudo tar xvzf \
    &gt; ~/jakarta-servletapi-3.2.3-src.tar.gz 
    moby:/opt/jakarta &gt; sudo ln -s jakarta-servletapi \
    &gt; jakarta-servletapi-3.2.3-src
    moby:/opt/jakarta &gt; cd jakarta-servletapi
    moby:/opt/jakarta/jakarta-servletapi &gt;
    </pre>
</td></tr>
</table>
<p>
I was ready to build the jakarta servlet libraries, using the
build.sh script supplied.  But it was at this point I had to "cheat"
in order to resolve two library related errors: 

<p>
<table CLASS="errormsg">
<caption>Error messages due to libraries not being found</caption>
<tr><td>
    <pre>

    moby:/opt/jakarta/jakarta-servletapi &gt; sudo sh build.sh dist
    Exception in thread "main" java.lang.NoClassDefFoundError:
    org/apache/tools/ant/Main

    /opt/jakarta/jakarta-servletapi-3.2.3-src/build.xml:31: Cannot use
    classic compiler, as it is not available A common solution is to set
    the environment variable JAVA_HOME to your jdk directory.
    </pre>
</td></tr>
</table>
<p>

The error messages <i>look</i> different, but are really both related
to libraries not being found.  The first is related to ant.jar, the
second is due to a "lost" tools.jar library. To solve these problems I
created two symlinks under $JAVA_HOME/jre/lib/ext to allow Java to 
find the newly created ant.jar and tools.jar libraries.<br> 

<p>
<table CLASS="sourcecode">
<caption>Symlinks set to allow Java to find "lost" Libraries</caption>
<tr><td>
    <pre>

    $JAVA_HOME/jre/lib/ext/ant.jar -&gt; /opt/jakarta/jakarta-ant/build/lib/ant.jar
    $JAVA_HOME/jre/lib/ext/tools.jar -> /usr/java/jdk1.3.1/lib/tools.jar
    </pre>
</td></tr>
</table>
<p>

Alternately I know of two other options that <i>should</i> work (but
did not for me):<p> 
<ol>
    <li>modify the $CLASSPATH environmental variable to include tools.jar
    and ant.jar explicitly.<br>
    <TT>export
    CLASSPATH=$JAVA_HOME/lib/tools.jar:$ANT_HOME/lib/ant.jar</TT>
    <br><em>or</em>
    <li>
    Explicitly specify the "-classpath" option when calling
    java. This is probably impractical for any large run script.
</ol>
<br>

After creating these symlinks, the following command ran perfectly:
<p>
<table CLASS="sourcecode">
<caption>Building Tomcat</caption>
<tr><td>
    <pre>

    moby:/opt/jakarta/jakarta-servletapi > sudo sh build.sh dist
    </pre>
</td></tr>
</table>
<p>
<a href="misc/peda/build_servlet_api.txt">Here is the output of servlet build
script</a><p>

<h2>Building Tomcat</h2>
Finally, the moment of truth, building the Jakarta-Tomcat package.  I
still had one error, 
<p>
<table CLASS="errormsg">
<caption>Error messages due to bin directory not being found</caption>
<tr><td>
    <pre>

    moby:/opt/jakarta/jakarta-tomcat > sudo sh ./build.sh dist
    Buildfile: build.xml
    prepare:
    BUILD FAILED
    /opt/jakarta/jakarta-tomcat-3.2.3-src/build.xml:32: /opt/jakarta/jakarta-ant-1.3/bin not found.
    
    Total time: 2 seconds
    </pre>
</td></tr>
</table>
<p>
The error message, unlike most, is obvious. After symlinking the bin
directory in jakarta-ant, it ran perfectly. 
<p>
<table CLASS="sourcecode">
<caption>Symlink so the binaries could be found</caption>
<tr><td>
    <pre>

    moby:~ > cd /opt/jakarta/jakarta-ant
    moby:/opt/jakarta/jakarta-ant &gt; sudo ln -s bootstrap/bin .
    </pre>
</td></tr>
</table>
<p>

Here is the <a href="misc/peda/build_tomcat.txt">output of the
Tomcat build script</a><p>
At this point you can cd to $JAKARTA_HOME/dist/tomcat/bin and run
startup.sh .
<p>
<table CLASS="sourcecode">
<caption>Starting Jakarta-Tomcat</caption>
<tr><td>
    <pre>

    moby:/opt/jakarta/dist/tomcat/bin &gt; sudo ./startup.sh
    Using classpath: /opt/jakarta/build/tomcat/classes:/opt/jakarta/build/tomcat/lib
    /servlet.jar:/opt/jakarta/build/tomcat/lib/test:/usr/java/jdk1.3.1/lib/tools.jar
    allan@moby:/opt/jakarta/build/tomcat/bin &gt; 2001-07-20 03:13:50 - ContextManager:
     Adding context Ctx( /examples )
    2001-07-20 03:13:50 - ContextManager: Adding context Ctx( /admin )
    Starting tomcat. Check logs/tomcat.log for error messages 
    2001-07-20 03:13:50 - ContextManager: Adding context Ctx(  )
    2001-07-20 03:13:50 - ContextManager: Adding context Ctx( /test )
    allan@moby:/opt/jakarta/build/tomcat/bin &gt; 2001-07-20 03:13:53 - \
    PoolTcpConnector: Starting HttpConnectionHandler on 8080
    2001-07-20 03:13:53 - PoolTcpConnector: Starting Ajp12ConnectionHandler on 8007
    </pre>
</td></tr>
</table>
<p>
Similarly with shutdown:
<p>
<table CLASS="sourcecode">
<caption>Stopping Jakarta-Tomcat</caption>
<tr><td>
    <pre>

    moby:/opt/jakarta/dist/tomcat/bin > sudo ./shutdown.sh 
    Using classpath:
    /opt/jakarta/build/tomcat/classes:/opt/jakarta/build \
    /tomcat/lib/servlet.jar:/opt/jakarta/build/tomcat/lib/test:/usr/java \
    /jdk1.3.1/lib/tools.jar
    Stop tomcat
    2001-07-20 03:15:47 - ContextManager: Removing context Ctx( /examples )
    2001-07-20 03:15:47 - ContextManager: Removing context Ctx( /admin )
    2001-07-20 03:15:47 - ContextManager: Removing context Ctx(  )
    2001-07-20 03:15:47 - ContextManager: Removing context Ctx( /test )
    </pre>
</td></tr>
</table>
<p>

Congratulations!  After running the startup script, you can view the
greeting screen by pointing your browser at the web server's machine,
port 8080, unless modified.<p>
<img src="misc/peda/tomcat_works.png" 
alt="Screencap of the Tomcat Demo Webserver Running" WIDTH="600" HEIGHT="587">
<p>
Jumping to the various pages supplied you can then check out the
screen shots of the example <a href="misc/peda/servlet_examples.html">Servlets</a> 
and <a href="misc/peda/jsp_samples.html">Java Server Pages</a>. This
is a bit of a tease, because you are tempted to try to run the demos
from the screencaps, but still it's nice to see what you can expect
when you actually get Jakarta Tomcat Running. 
<p>

<h2>It works!</h2>
At this point you have two servers running: a simple web server
listening on port 8080, and a servlet container application server
listening on port 8007. The first thing I am concerned with is the
fact that everything was set up as root.  Supporting documentation
suggests running the server as "nobody", but I felt that a special
jakarta user analogous to a database user would be a good idea because of
the special environmental variables that are set.  Having a dedicated
jakarta user just for servlets would then allow configuration to be kept in
the ~jakarta home directory.  This would be even more useful if there
were other versions of java installed on the system.
<p>

Anyhow this is all fairly simple.  After the jakarta user is set up as
shown, you can run jakarta as that user, and since it runs from a
nonpriviliged port there should be no problem there.  Still I thought
that the permissions could be tightened up more so that only the jakarta
user can run the servlet container, so I shutdown the server, and
changed the permissions as follows:<p> 

<p>
<table CLASS="sourcecode" >
<caption>Tightening Up Permissions</caption>
<tr><td>
    <pre>

    moby:/opt/jakarta &gt; sudo $TOMCAT_HOME/bin/shutdown.sh 
    moby:/opt/jakarta &gt; sudo /usr/sbin/groupadd jakarta
    moby:/opt/jakarta &gt; sudo /usr/sbin/useradd -g jakarta -c \
    &gt; "Java Server Pages" jakarta
    moby:/opt/jakarta &gt; sudo mkdir /home/jakarta
    moby:/opt/jakarta &gt; sudo chown jakarta.jakarta /home/jakarta
    moby:/opt/jakarta &gt; sudo chown -R jakarta.jakarta $JAKARTA_HOME
    moby:/opt/jakarta &gt; sudo su - jakarta
    moby:~ &gt; cd $JAKARTA_HOME
    </pre>
</td></tr>
</table>
<p>

Naturally you could set the password too, but since root can get in
anyhow, I didn't bother.  I decided to tighten some permissions by using 
 <a href="misc/peda/tighten_perms.sh.txt">this</a> script.
Now only user jakarta can start and stop the servlets, and Java server
pages. The environmental variables set in /etc/profile or
 /etc/profile.local can now be set instead in ~jakarta/.profile or
 ~jakarta/.bash_profile leaving other users free to choose other java
 versions and reducing the count of environmental variables.
<p>
Now that Tomcat is running, you can experiment with altering the stock
configuration.  There are many options here, and of course since
Jakarta is a project by the Apache foundation, it is designed to
integrate easily with Apache. Take a look at the users guide
included with the source, it provides some good examples, and
you can also consult the project <a href="#tomcat_ug">web site</a>.  
XML is the native format of it's configuration file, and you'll be
getting a crash course in XML, it you haven't learned about it yet.
To get you started, see the main configuration files, "server.xml" and
"web.xml". 
<p>
So welcome to the wild world of Java Server Pages and Servlets.
You'll find that it's a very mature in interesting technology.  Good
luck.
<p>
<hr>
References:
<ol>
<li>Linux as an Application Server -- The Tomcat Way<br>
    by Chris Bush
    <a href="http://www.sysadminmag.com/linux/articles/v10/i01/a4.htm">http://www.sysadminmag.com/linux/articles/v10/i01/a4.htm</a>

<li><a name="java_download">Sun's Java Software Development Kit 1.3.1</a><br>
    <a href="http://java.sun.com/products/">http://java.sun.com/products/</a>

<li><a name="java_sse">Java Secure Sockets Extension (JSSE) version 1.0.2 or later</a><br>
    <a href="http://java.sun.com/products/jsse/">http://java.sun.com/products/jsse/</a>

<li><a name = "java_xml">Java API for XML Parsing implementation 1.1</a><br>
    <a href="http://java.sun.com/xml">http://java.sun.com/xml</a>

<li><a name="jakarta_download">Jakarta Tomcat download (includes
Jakarta Tomcat, ANT, Servlet API)</a><br>
    <a href="http://jakarta.apache.org/site/sourceindex.html">http://jakarta.apache.org/site/sourceindex.html</a><br>
    Note that Ant is a separate project, but the servlet API source is in the
    same download directory as the Jakarta-Tomcat source.

<li>Build secure network applications with SSL and the JSSE API<br>
    by Todd Sundsted
    <a href="http://www.javaworld.com/javaworld/jw-05-2001/jw-0511-howto.html">http://www.javaworld.com/javaworld/jw-05-2001/jw-0511-howto.html</a>

<li>The Ant FAQ:
    <a href="http://jakarta.apache.org/ant/faq.html">http://jakarta.apache.org/ant/faq.html</a>
<li><a name="tomcat_ug">The Tomcat Users Guide</a><br>
    <a href="http://jakarta.apache.org/tomcat/tomcat-3.3-doc/tomcat-ug.html">http://jakarta.apache.org/tomcat/tomcat-3.3-doc/tomcat-ug.html</a>

</ol>






<!-- *** BEGIN bio *** -->
<SPACER TYPE="vertical" SIZE="30">
<P> 
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Allan Peda</H4>
<EM>Allan has been enjoying Linux since about 1995, discovering Perl shortly
thereafter. Currently he is doing Linux consulting work in the NYC area.
He enjoys surfing, sailing, and dreams of owning a charter boat in
</EM>tranquilo<EM> Costa Rica.</EM>


<!-- *** END bio *** -->

<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P --> 
<H5 ALIGN=center>

Copyright &copy; 2001, Allan Peda.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR> 
Published in Issue 69 of <i>Linux Gazette</i>, August 2001</H5>
<!-- *** END copyright *** -->


<H4 ALIGN="center">
"Linux Gazette...<I>making Linux just a little more fun!</I>"
</H4>

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

<center>
<H1><font color="maroon">Qubism</font></H1>
<H4>By <a href="mailto:sirflakey@core.org.au">Jon "Sir Flakey" Harsem</a></H4>
</center>
<P> <HR> <P>  

<!-- END header -->


Vi-Agra (of HelpDex fame) makes a cameo appearance in two Qubism cartoons.

<P>

<IMG ALT="qb-hug.jpg" SRC="misc/qubism/qb-hug.jpg" 
	WIDTH="683" HEIGHT="306">
<BR CLEAR="all">

<IMG ALT="qb-joyride.jpg" SRC="misc/qubism/qb-joyride.jpg" 
	WIDTH="750" HEIGHT="308">
<BR CLEAR="all">

<IMG ALT="qb-magnify.jpg" SRC="misc/qubism/qb-magnify.jpg" 
	WIDTH="800" HEIGHT="310">
<BR CLEAR="all">

<IMG ALT="qb-vi-agra.jpg" SRC="misc/qubism/qb-vi-agra.jpg" 
	WIDTH="682" HEIGHT="310">
<BR CLEAR="all">

<IMG ALT="qb-ota.jpg" SRC="misc/qubism/qb-ota.jpg" 
	WIDTH="767" HEIGHT="306">
<BR CLEAR="all">

<IMG ALT="qb-pt.jpg" SRC="misc/qubism/qb-pt.jpg" 
	WIDTH="604" HEIGHT="310">
<BR CLEAR="all">

<IMG ALT="qb-pt2.jpg" SRC="misc/qubism/qb-pt2.jpg" 
	WIDTH="465" HEIGHT="310">
<BR CLEAR="all">

<IMG ALT="qb-pt3.jpg" SRC="misc/qubism/qb-pt3.jpg" 
	WIDTH="605" HEIGHT="305">
<BR CLEAR="all">

<IMG ALT="qb-skywritten.jpg" SRC="misc/qubism/qb-skywritten.jpg" 
	WIDTH="777" HEIGHT="310">
<BR CLEAR="all">

<IMG ALT="qb-xpbeta.jpg" SRC="misc/qubism/qb-xpbeta.jpg" 
	WIDTH="800" HEIGHT="310">
<BR CLEAR="all">

<IMG ALT="qb-revert.jpg" SRC="misc/qubism/qb-revert.jpg" 
	WIDTH="800" HEIGHT="310">
<BR CLEAR="all">




<!-- *** BEGIN bio *** -->
<SPACER TYPE="vertical" SIZE="30">
<P> 
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Jon "SirFlakey" Harsem</H4>
Jon is the creator of the Qubism cartoon strip and current
Editor-in-Chief of the 
<A HREF="http://www.core.org.au/">CORE</A> News Site.  
Somewhere along the early stages of
his life he picked up a pencil and started drawing on the wallpaper.  Now
his cartoons appear 5 days a week on-line, go figure. He confesses to
owning a Mac but swears it is for "personal use".

<!-- *** END bio *** -->

<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P --> 
<H5 ALIGN=center>

Copyright &copy; 2001, Jon "Sir Flakey" Harsem.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR> 
Published in Issue 69 of <i>Linux Gazette</i>, August 2001</H5>
<!-- *** END copyright *** -->


<H4 ALIGN="center">
"Linux Gazette...<I>making Linux just a little more fun!</I>"
</H4>

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

<center>
<H1><font color="maroon">Numerical Workbenches</font></H1>
<H4>By <a href="mailto:cspiel@hammersmith-consulting.com">Christoph Spiel</a></H4>
</center>
<P> <HR> <P>  

<!-- END header -->




<p>Some people think GNU/Linux is a good operating system, but has not enough
applications to make it succeed in the market. Although this might be true for
the desktop area, it is certainly wrong for numerical workbenches. In this
field GNU/Linux users have many different (and excellent) choices -- in
fact too many to introduce them all. Therefore, this series of articles
introduces three outstanding applications:</p>

<dl>
<dt><strong><a name="item_GNU%2FOctave_2%2E1%2E34">GNU/Octave
2.1.34</a></strong><br>
</dt>

<dd><a href="http://www.che.wisc.edu/octave/">
http://www.che.wisc.edu/octave/</a></dd>

<dt><strong><a name="item_Scilab_2%2E6">Scilab 2.6</a></strong><br>
</dt>

<dd><a href="http://www-rocq.inria.fr/scilab/">
http://www-rocq.inria.fr/scilab/</a></dd>

<dt><strong><a name="item_Tela_1%2E32">Tela 1.32</a></strong><br>
</dt>

<dd><a href="http://www.geo.fmi.fi/prog/tela.html">
http://www.geo.fmi.fi/prog/tela.html</a></dd>
</dl>

<p>To find out about more numerical workbenches, check out <a href=
"http://sal.kachinatech.com/A/2/">http://sal.kachinatech.com/A/2/</a></p>

<h2><a name="introduction">Introduction</a></h2>

<p>What can these programs do? Isn't paper and pencil -- er -- a
spreadsheet program enough?</p>

<p>The main application areas of numerical workbenches are:</p>

<ul>
<li>Preprocessing (yes -- meanwhile we need computers to talk to
computers) and postprocessing data with the special case of ``gluing'' two
numerical applications together.</li>

<li>Numerical optimizations (both, linear and non-linear),</li>

<li>Standalone simulations,</li>

<li>Data visualization,</li>

<li>Sophisticated ``pocket'' calculators,</li>

<li>Rapid prototyping of specialized numerical applications, which finally
will be implemented in, say, C++ or Fortran-90.</li>
</ul>

<p>However, because all of them provide complete programming languages to the
user and, moreover, are designed to be extended, the number of numerical
problems they can solve is almost limitless.</p>

<h3><a name="numerical mathematics">Numerical Mathematics</a></h3>

<p>Now, what the heck is numerical math anyhow? Numerical Mathematics is the
branch of math that develops, analyzes, and applies methods to compute with
finite precision numbers. Computer hardware, for example, uses numerical math.
</p>

<p>Why do computers work with finite precision numbers?  Why has nobody
developed a scheme that allows for the storage of exact numbers?</p>

<ol>
<li>Solving problems with finite precision numbers is faster -- much, much
faster. Take for example the sum of all square roots from one to one million.
On my computer, doing the exact computation with MuPAD-1.4.2 available at <a
href="http://math-www.uni-paderborn.de/MuPAD/index.html">
http://math-www.uni-paderborn.de/MuPAD/index.html</a> 

<pre>
    time(sum(sqrt(i), i = 1..10^6));
</pre>

<p>takes about 40&nbsp;seconds, whereas getting the approximate result with
Tela-1.32</p>

<pre>
    tic(); sum(sqrt(1:10^6)); toc();
</pre>

<p>takes 0.31&nbsp;seconds, that is, the answer in finite precision is
returned over 100&nbsp;times faster! Put another way, we can crunch hundred
times more data with finite precision numbers in the same time slice.</p>
</li>

<li>When using good algorithms -- the ones suggested by numerical
mathematicians -- and being careful one can get surprisingly precise
answers even with finite precision numbers.<p></p></li>

<li>Admit it, most of the time users do not need exact results! A good
approximation -- with ``sufficiently many correct digits'' -- will
do.<p></p></li>
</ol>

<h3><a name="article organization">Article Organization</a></h3>

<p>In this article series, we point out the similarities among the three
applications that we are going to discuss. We will use GNU/Octave in most of
the examples. Where there are important differences you should be aware of, we
have put a <strong>Differences</strong> paragraph at the end of the section.</p>

<p>Technical details for the terminally curious have been put in <strong>
Details</strong> sections.</p>

<h2><a name="getting in and out">Getting In and Out</a></h2>

<p>To give you a hands-on experience, let us start each of the applications,
request help on a function, and then quit.</p>

<dl>
<dt><strong><a name="item_GNU%2FOctave">GNU/Octave</a></strong><br>
</dt>

<dd>
<pre>
    cspiel@hydra:~/articles/numerical-workbenches $ octave
    GNU Octave, version 2.1.34 (i686-pc-linux-gnu).
    Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001 John W. Eaton.
    This is free software with ABSOLUTELY NO WARRANTY.
    For details, type `warranty'.
</pre>

<pre>
    *** This is a development version of Octave.  Development releases
    *** are provided for people who want to help test, debug, and improve
    *** Octave.
    ***
    *** If you want a stable, well-tested version of Octave, you should be
    *** using one of the stable releases (when this development release
    *** was made, the latest stable version was 2.0.16).
</pre>

<pre>
    octave:1&gt; help diag
    diag is a built-in function
</pre>

<pre>
     - Built-in Function:  diag (V, K)
         Return a diagonal matrix with vector V on diagonal K.  The second
         argument is optional.  If it is positive, the vector is placed on
         the K-th super-diagonal.  If it is negative, it is placed on the
         -K-th sub-diagonal.  The default value of K is 0, and the vector
         is placed on the main diagonal.  For example,
</pre>

<pre>
              diag ([1, 2, 3], 1)
              =&gt;  0  1  0  0
                       0  0  2  0
                       0  0  0  3
                       0  0  0  0
</pre>

<pre>
    octave:2&gt; quit
    cspiel@hydra:~/articles/numerical-workbenches $
</pre>

<p>Alternatively use <code>exit</code> or press <strong>C-d</strong> to quit
GNU/Octave.</p>

<p>GNU/Octave offers the user function-name completion, this is, when only
part of a function's name is entered and the user hits <strong>Tab</strong>,
the partial name is completed as much as possible. A second <strong>
Tab</strong> displays the list of remaining choices.</p>
</dd>

<dt><strong><a name="item_Scilab">Scilab</a></strong><br>
</dt>

<dd>After starting Scilab thus:

<pre>
    cspiel@hydra:~/articles/numerical-workbenches $ scilab
</pre>

<p>we get a new <a href="misc/spiel/scilab-main.png">X-window</a> in which the
Scilab interpreter runs.  Asking for help opens an 
<a href="misc/spiel/scilab-xless-help.png">xless(1x) window</a>.
(Both these links are screenshots, so click on them.)</p>

<p>To exit Scilab, enter <code>quit</code> or <code>exit</code>.</p>

<p>Scilab can also be launched in non-window mode by passing the <code>
-nw</code> option to it:</p>

<pre>
    cspiel@hydra:~/articles/numerical-workbenches $ scilab -nw
                               ===========
                               S c i l a b
                               ===========
</pre>

<pre>
                              scilab-2.6
                      Copyright (C) 1989-2001 INRIA
</pre>

<pre>
    Startup execution:
      loading initial environment
</pre>

<pre>
    --&gt;help diag
</pre>

<p>The help system then uses the text output, too.</p>
</dd>

<dt><strong><a name="item_Tela">Tela</a></strong><br>
</dt>

<dd>Tela's banner is quite terse, nonetheless, the help system is as
comprehensive as necessary. Note that Tela offers function name completion as
GNU/Octave does. 

<pre>
    cspiel@hydra:~/articles/numerical-workbenches $ tela
    This tela is a tensor language, Version 1.32.
    Type  ?help  for help.
    -&gt;TAB completion works; try docview() and source("demo")
    &gt;help diag
    diag(V, K) (V is a vector) returns a square diagonal matrix, with
       vector V on the main diagonal (K == 0, default), the K-th super
       diagonal (K &gt; 0) or the K-th sub-diagonal (K &lt; 0).
</pre>

<pre>
       diag(M, K) (M is a matrix) returns the main diagonal (K == 0,
       default), the K-th super diagonal (K &gt; 0), or the K-th sub-diagonal
       (K &lt; 0) of M as a vector.  M need not necessarily be square.
</pre>

<pre>
    &gt;quit()
    63 instructions, 0 arithmetic ops.
    0.0063 MIPS, 0 MFLOPS.
    cspiel@hydra:~/articles/numerical-workbenches $
</pre>

<p>Tela can also be exited by pressing <strong>C-d</strong>.</p>
</dd>
</dl>

<h2><a name="better than a pocketcalculator!">Better Than a
Pocket Calculator!</a></h2>

<p>Now that we know how to start and exit the programs, let us look at them in
action.</p>

<h3><a name="simple expressions">Simple Expressions</a></h3>

<p>We want to see:</p>

<ol>
<li>Whether we can write mathematical expressions the way we are used to from
school. Ugh! 
<BR><code>1&nbsp;+&nbsp;2&nbsp;*&nbsp;3&nbsp;^&nbsp;4</code> should be treated 
as <code>1&nbsp;+&nbsp;(2 *&nbsp;(3&nbsp;^&nbsp;4))</code>, yielding 
<code>163</code>.  It should not be treated as
<code>((1&nbsp;+&nbsp;2)&nbsp;*&nbsp;3)&nbsp;^&nbsp;4</code>, which equals 
<code>6561</code>,</li>

<li>How many bits are necessary to store <code>10^6</code>, and</li>

<li>How steep is our driveway? (measured in degrees) 
Our garage is 7&nbsp;meters away from the street and half a meter above
it.</p>
</li>
</ol>

<p>Here we go.</p>

<pre>
    cspiel@orion:~/articles/numerics $ octave
</pre>

<p>All three programs are console-based.  That is, the user gets a prompt
whenever the application is ready to accept input. We enter our first question
as we write it on paper. Hitting return terminates the line, the program
evaluates it, and returns the result in variable&nbsp;<code>ans</code> (more on
variables later).</p>

<pre>
    octave:1&gt; 1 + 2 * 3 ^ 4
    ans = 163
</pre>

<p>Aha, obviously GNU/Octave knows elementary-school math!</p>

<p>Our second question requires the logarithm function&nbsp;<code>log</code>,
which returns the natural logarithm of its argument; this is, the logarithm to
base&nbsp;<em>e</em>.</p>

<pre>
    octave:2&gt; log(10^6) / log(2)
    ans = 19.932
</pre>

<p>We conclude that 1,000,000 needs 20&nbsp;bits to be stored.</p>

<p>Finally, how steep is our driveway? What we need here is an angular
function, namely the arctangent, written as <code>atan(argument)</code>.</p>

<pre>
    octave:3&gt; atan(0.50 / 7.0)
    ans = 0.071307
</pre>

<p>Hmm, ain't that a bit too flat? Digging out the wisdom of long forgotten
math classes, we remember that the arctangent of 1 is 45 degrees. Let us check
this!</p>

<pre>
    octave:4&gt; atan(1)
    ans = 0.78540
</pre>

<p>Ouch, off by a factor of 57! Do we have to throw the program away? Wait
-- 57 equals almost 180&nbsp;over&nbsp;<em>pi</em>. This means GNU/Octave
has returned the result in radians, not in degrees. All angular functions work
in units of radians, this is, an angle of 360 degrees is equivalent
2&nbsp;<em>pi</em>&nbsp;radians.</p>

<p>We try again, supplying the correct conversion factor:</p>

<pre>
    octave:5&gt; atan(0.50 / 7.0) * 360/(2 * 3.14)
    ans = 4.0856
</pre>

<p>Approximately 4&nbsp;degrees, that looks good.  Our garage certainly won't
get flooded in the next deluge.</p>

<p><strong>Details</strong></p>

<ul>
<li>Numbers are either real-valued or complex-valued. Elementary operations
``+'', ``-'', ``*'', and ``/'', as well as exponentiation&nbsp;``^'' work as
expected on reals and complex numbers.</li>

<li>The commonly used basic functions are the absolute value <code>
abs(arg)</code>, the sign-function <code>sign(arg)</code>, and the square root
<code>sqrt(arg)</code>.</li>

<li>Two logarithm functions are supplied, one to the base of <em>e</em>:
<code>log(arg)</code>, and to the base of 10: <code>log10(arg)</code>. The
exponential <code>exp(arg)</code> is the inverse of <code>
log(arg)</code>.</li>

<li>All workbenches offer a wealth of angular and hyperbolic functions: <code>
sin(arg)</code>, <code>cos(arg)</code>, <code>tan(arg)</code>, <code>
sec(arg)</code>, <code>csc(arg)</code>; <code>asin(arg)</code>, <code>
acos(arg)</code>, <code>atan(arg)</code>, <code>acsc(arg)</code>; <code>
sinh(arg)</code>, <code>cosh(arg)</code>, <code>tanh(arg)</code>, <code>
sech(arg)</code>, <code>csch(arg)</code> <code>asinh(arg)</code>, <code>
acosh(arg)</code>, <code>atanh(arg)</code>, <code>acsch(arg)</code>.</li>
</ul>

<p><strong>Differences</strong></p>

<ul>
<li>Tela does not know the convenience variable <code>ans</code>.</li>

<li>In GNU/Octave and Tela imaginary literal numbers are written by appending
``i'', ``j'', ``I'', or ``J'' to a number. For example <code>1i</code>, <code>
-8.99I</code>, <code>324J</code>. Scilab defines a special constant for the
imaginary unit <code>sqrt(-1)</code>, which is written &lt;%i&gt;. Therefore,
Scilab's imaginary literals look like products: <code>-8.99*%i</code>, <code>
%i*324</code>.</li>
</ul>

<h3><a name="variables">Variables</a></h3>

<p>In the last section we have not gained much in comparison with a pocket
calculator, have we? The first feature where our programs beat pocket
calculators and spread-sheets are names that we can give parameters or
results; these are called variables.</p>

<p>Assume our better half wants us to build a garden in the yard, but we want
to watch basketball. Therefore we quickly need a hard figure that proves we
don't have enough compost for the desired size. Ha -- brilliant
idea!</p>

<img height="281" alt="[image: plan for a flower bed]" src=
"misc/spiel/patch.png" width="551">
<BR CLEAR="all">

<p>From our little plan we take the following lengths in feet:</p>

<pre>
    houseside_length = 10
    creekside_length = 6
    width = 2
</pre>

<p>Our better half also said the layer of new soil ought to be at least 
five inches, so</p>

<pre>
    height = 5 / 12
</pre>

<p>GNU/Octave to the rescue!</p>

<pre>
    octave:1&gt; houseside_length = 10
    houseside_length = 10
    octave:2&gt; creekside_length = 6
    creekside_length = 6
    octave:3&gt; width = 2
    width = 2
    octave:4&gt; height = 5 / 12
    height = 0.41667
    octave:5&gt; volume = (houseside_length + creekside_length) * width * height
    volume = 13.333
</pre>

<p>The compost box is 6' x 4' and currently holds eight inches of usable
compost.</p>

<pre>
    octave:6&gt; box_width = 6
    box_wight = 6
    octave:7&gt; box_depth = 4
    box_depth = 4
    octave:8&gt; compost_height = 8/12
    compost_height = 0.66667
    octave:9&gt; compost_volume = box_width * box_depth * compost_height
    compost_volume = 16
</pre>

<p>Oh no, we have just dug our own grave. We have got <em>enough</em> compost!
What about taping the match on the VCR?</p>

<p><strong>Details</strong></p>

<ul>
<li>Variables spring into existence when they are first assigned to.</li>

<li>It is not an error to assign a value of different type to an existing
variable. (Currently, we only know of one type, but more types are waiting for
us)</li>

<li>Using a undefined variable on the right-hand side of an assignment causes
an error.</li>
</ul>

<h2><a name="structured data">Structured Data</a></h2>

<p>Until now we have not exploited where computers are really good at:
repetitive work.</p>

<h3><a name="vectors">Vectors</a></h3>

<p>Say we got a long receipt from the grocery store. [Your ad here!]  How can
we get the VAT in Dollars on each item given the gross amount and the VAT rate
in percent? The formula</p>

<pre>
            vat_percent / 100
    vat = --------------------- * gross_amount
          1 + vat_percent / 100
</pre>

<p>is trivial, but we want to save us repeated typing.</p>

<p>The list of all gross amounts in the receipt forms what numerical programs
call a <em>vector</em>. Vectors are built from values by enclosing these
values in square brackets and separating them with commas like this:</p>

<pre>
    octave:1&gt; gross = [1.49, 4.98, 0.79, 5.49, 0.96, 0.96, 0.96, 0.96]
    gross =
</pre>

<pre>
      1.49000  4.98000  0.79000  5.49000  0.96000  0.96000  0.96000  0.96000
</pre>

<p>The vector is built from left to right using our supplied numbers in the
same order that we enter them.</p>

<p>Wouldn't it be wonderful if we simply wrote: <code>gross *
(vat_percent/100) / (1 + vat_percent/100)</code> and get the VAT of each item?
It really is that simple.</p>

<pre>
    octave:2&gt; vat_percent = 7
    vat_percent = 7
    octave:3&gt; a = (vat_percent/100) / (1 + vat_percent/100)
    a = 0.065421
    octave:4&gt; vat = a * gross
    vat =
</pre>

<pre>
      0.097477  0.325794  0.051682  0.359159  0.062804  0.062804  0.062804  0.062804
</pre>

<p>Wow -- it works! For the first time we have really gained convenience
and expressiveness: a single multiplication sign performs eight
multiplications in a row.</p>

<p>What has happened? <code>vat_percent</code> is a single value, which is
called <em>scalar</em> in numerics to distinguish it from vectors. Well, if
<code>vat_percent</code> is a scalar, then <code>vat_percent/100</code>,
<code>1 + vat_percent/100</code>, and <code>a</code> are scalars, too.
Finally, scalar&nbsp;<code>a</code> must be multiplied with vector&nbsp;<code>
gross</code>. What we wanted and what happened was that <code>a</code> was
multiplied in turn with every element of <code>gross</code>. This holds for
every operator, not only multiplication! In general</p>

<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<em>vector</em>&nbsp;<em>
op</em>&nbsp;&nbsp;<em>scalar</em></p>

<p>and</p>

<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<em>scalar</em>&nbsp;<em>
op</em>&nbsp;&nbsp;<em>vector</em></p>

<p>apply <em>scalar</em> to every element in <em>vector</em> according to
operation <em>op</em>. In our example, this is as if we had written the
following</p>

<pre>
    vat(1) = a * gross(1)
    vat(2) = a * gross(2)
    ...
    vat(8) = a * gross(8)
</pre>

<p>where we have introduced a new piece of syntax: vector indexing. Each
element (a scalar) of a vector can be accessed by its <em>index</em>, which is
the number of it's place in the vector. The index is written in parenthesis
after the vector. For example, to get the second element in <code>
gross</code>, we write</p>

<pre>
    octave:5&gt; gross(2)
    ans = 4.9800
</pre>

<p>Elements in vectors can be assigned to with the same syntax. Just place the
indexed vector to the left of the assignment sign, for example, <code>gross(2)
= 5.12</code>.</p>

<p>What else can be thought of as a vector of numbers besides our receipt? Any
series of values! Most of the time the values will be related, like the
temperature measured each day at 8am, the diameters of a batch of metal rods,
the velocities of all westbound traffic across Buffalo Street at the corner of
West Clinton Street on Wednesday April&nbsp;18, 2001. As we are living in the
Digital Age, many more series of data fit the notion of a vector: every piece
of music on a CD is a vector of sound amplitudes and the indices mark discrete
moments in time.</p>

<p><strong>Details</strong></p>

<ul>
<li>Mathematically speaking what we call vectors here are tuples.</li>

<li>Most built-in functions, for example <code>sin</code>, can be used on
vectors. 

<pre>
    v = [0.12, 0.89, 0.78, 0.10]
    sin(v)
</pre>

<p>or</p>

<pre>
    sin([0.12, 0.89, 0.78, 0.10])
</pre>
</li>

<li>Vectors do not have to be built from scalars; more than one vector can be
catenated with the same syntax. Furthermore, the elements used in the
definition of the vector do not have to be literal numbers, but can be
arbitrary expressions, which again yield scalars or vectors.</li>
</ul>

<p><strong>Differences</strong></p>

<ul>
<li>Tela uses a different syntax for vector construction, which resembles
Scheme or Smalltalk: The vector is surrounded by parentheses which are
preceded by a sharp sign; for example: <code>gross = #(1.49, 4.98, ...,
0.96)</code>.</li>

<li>Tela uses a different syntax for vector indexing, which resembles Pascal.
The index is enclosed in square brackets; for example: <code>gross[2]</code>.
Warning for C programmers: Though the square brackets look like C, the lowest
index always is 1.</li>
</ul>


<h2>Next Month</h2>

<ul>
<li>Matrices</li>

<li>User defined functions</li>

<li>Flow control statements</li>

<li>Input and output</li>
</ul>





<!-- *** BEGIN bio *** -->
<SPACER TYPE="vertical" SIZE="30">
<P> 
<H4><IMG ALIGN=BOTTOM ALT="" SRC="../gx/note.gif">Christoph Spiel</H4>
<EM>Chris runs an Open Source Software consulting company in Upper Bavaria/Germany.
Despite being trained as a physicist -- he holds a PhD in physics from Munich
University of Technology -- his main interests revolve around numerics,
heterogenous programming environments, and software engineering.  He can be
reached at 
<A
HREF="mailto:cspiel@hammersmith-consulting.com">cspiel@hammersmith-consulting.com</A>.</EM>

<!-- *** END bio *** -->

<!-- *** BEGIN copyright *** -->
<P> <hr> <!-- P --> 
<H5 ALIGN=center>

Copyright &copy; 2001, Christoph Spiel.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR> 
Published in Issue 69 of <i>Linux Gazette</i>, August 2001</H5>
<!-- *** END copyright *** -->


<H4 ALIGN="center">
"Linux Gazette...<I>making Linux just a little more fun!</I>"
</H4>

<P> <hr> <P> 

<H1><font color="maroon">The Back Page</font></H1>

<ul>
<li><a HREF="#wacko">Wacko Topic of the Month</a>
<li><a HREF="#nottag">Not The Answer Gang</a>
<li><a HREF="#spam">World of Spam</a>
</ul>

<a name="wacko"></a>
<P> <hr> <P> 
<!--====================================================================-->

<center><H3><font color="maroon">Wacko Topic of the Month</font></H3></center>

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

<FONT COLOR="purple">
[Ben] O'course, "linux" _could_ just be another type of rhubard... &lt;sic&lt;
*that* would explain some things. :)
</FONT>




<a name="nottag"></a>
<P> <hr> <P> 
<!--====================================================================-->

<center><H3><font color="maroon">Not The Answer Gang</font></H3></center>

<P> <HR> <P> 
<!--======================================================================-->
<P>
<H3 ALIGN="center">Homework assignment: reading directions</H3>

<p align="right"><FONT COLOR="#000000"><strong>Answered By Iron
</strong></FONT></p>

<STRONG>
question 1. using the man page on a linux work station identify four flags that 
can be supplied to the shutdown command . giving the description of each flag.

<P> question 2. using the man page on linux work station find out what three 
options can be used with the Is command .include a brief descrption of how the 
output will be formatted.
</STRONG></P>

<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Iron]

It says right in the question what to do.  Which part of "using the man page" do
you not understand?

<P> But here's a hint: there is no 'Is' command.  Do you mean 'ls'?  But it has a lot more than
three options.

<HR NOSHADE WIDTH="40%" ALIGN="center"> <!-- ************************************** -->

<H3 ALIGN="center">Homework assignment: American colonists</H3>

<p align="right"><FONT COLOR="#000000"><strong>Answered By Frank Rodolf, Heather
Stern, Iron and Huibert Alblas
</strong></FONT></p>

<STRONG>
1 question

<P> what methods did colonists use to protest actions by parliament between 1765 
and 1775
</STRONG></P>

<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Frank]

Hmm... Lets see if a European can answer that...

<P> My first guess was they dropped penguins in the parliamentary buildings. I
don't think that is correct though.

<P> I guess you did not realize you were sending this question to a list that is
about helping people with problems with Linux, a computer operating system,
not a homework help line. :)

<P> You might go to a search engine - www.google.com might be a good choice, and
search for (for instance):

               rebellion 1765-1775


<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Heather]

We (The Answer Gang) 
are not a study group. Most especially not a USA 
History 101 study group.

<P> The only way you could have found us is because we: 
<OL>
<LI> regularly advise people asking us questions that are
   poorly phrased to "do their homework first".
<LI> advise people who send us pieces of their computing
   exams in college that they can ask us these things,
   but it's no substitute for doing their homework. We
   then welcome them to read the rest of the Gazette.
</OL>

<P> Ask instead:

<H4>Q.</H4>
What methods did high school and college students use 
to study the late 1700s before the internet promised
them a fast answer to everything?

<H4>A.</H4> 
Books.  There is probably a library near you.  Failing 
that the textbook that was suggested by your professor
may have the answer in it, or a bibliography leading 
to more useful books.  Reading such books and thereby
gaining an understanding of the question and its 
answers... there may be many... is called "research"
and you can probably do an internet search on any 
buzzwords you find that way.

<P> Good luck in your quest.  And your quizzes.


<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Iron]

The Boston tea party.

<P> That inspired the Silicon Valley tea party some 200 years later.
<A HREF="http://www.svlug.org/events/tea-party-199811.shtml">
http://www.svlug.org/events/tea-party-199811.shtml</A>


<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Halb]

Nope, actualy the colonist were sick and tired from the English trying
to impose somekind off copyrightlisencefees and taxes on
software,mp3,linux,_stamps_,and everything but the kitchensink.

<P> The colonist reacted in not using M$-windows anymore and burning some
MP3 cd's.

<P> Get the real story on:
<A HREF="http://www.britannica.com/eb/article?euq187&tocid=0">
http://www.britannica.com/eb/article?euq187&tocid=0</A>

<P> This Brittanica thing is quite good, I wish it had been there back then
when I was supposed to do my history homework.....


<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Iron]
Never mind the irony of looking up the American Revolution in a British
encyclopedia!





<HR NOSHADE WIDTH="40%" ALIGN="center"> <!-- ************************************** -->

<H3 ALIGN="center">Homework assignment: modernizing an office</H3>

<p align="right"><FONT COLOR="#000000"><strong>Answered By Heather Stern
</strong></FONT></p>

<STRONG>
respected sir;(to whom it may concern)
i have visited ur webpage
</STRONG></P>

<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Heather]
You may have visited them, but you haven't read them... or you'd know we
don't answer for the operating systems you have asked about.  Or else you
don't mind taking a few flames, because you hope there will be a useful
tidbit anyway.  If that's so, please read onward.

<P>
<STRONG>
ir i am student of IT and want ur help in solving my college assignment, as 
it is tecnically advanced ur i think u can give me help.
points of the asssignments are;
</STRONG>

<P>
With a certain amount of rolling our eyes towards the heavens... who told
you to mail us?

If you just found us in some search engine, that would be because the 
buzzword "homework" is part of the commonly used phrases here:

<UL>
<LI> SO you have some homework to do.
<LI> Trying to get us to do your homework, eh?
</UL>

When we answer these sorts of questions it is nearly always with some 
better places to look.  The 
<A HREF="http://www.linuxdoc.org/">Linux Documentation Project</A>, for
instance. 

<P> Shall we send a carbon copy of this message to your professor, too?

<P> I think you can stand to read the back issues of the Linux Gazette in some
detail.  This is a very old practice in schools called "research".  I've
heard that some people get better answers from technical forums when they
try to do some of it before just dumping their take-home exam in someone
else's lap.

<P>
<STRONG>
The company is tradionalist in information privacy, security, and the 
applications of new technologies: so

<P> 1)if i am doing job in World computer inc.and i have to upgrade the system 
into modern arena
</STRONG>

<P> Can't "up" grade until you know what you want it to do.  If it is already
doing its job well, "up" grading it is a waste of your time, and annoys 
the users.

<P>
<STRONG>
Q1)from security point of view ...
</STRONG>

<P> To quote another member of The Answer Gang:
<blockquote>
	"Security is the enforcement of policy.  First you must set 
	 policy, then you can try to enforce it."
</blockquote>

<P> Not all security policies are about computers - for those, there is only
a slight amount software can do. 

<P>
<STRONG>
... which software is better Sun solaris or Windows NT.and which of them
can better ...
</STRONG>

<P> can [verb] better?
We don't care which of those two is better - FOR WHAT? - this is the 
<EM>LINUX</EM> Gazette.

<P>
<STRONG>
...in the environment of data processsing deapartmant.
</STRONG>

<P> I hope you would better know the context of a data processing department
than I would, because those aren't the kind of sites I work with most.  I
have no idea if COBOL exists for either one.

<P> But you might try Celeste Stokely's home page, it has much more general
UNIX related information.  And some humor.

<P>
<STRONG>
so plz give me strengths and of the software u recommend----?
</STRONG>

<P> Yes, if you're used to Sun versions of UNIX, try Slackware as your Linux
distribution.  It's very "BSDish" which means some of its commands may be
more comfortable to use.  KDE or Openlook window managers might resemble
the default X interfaces found on Suns.  And you'll need Samba to talk to 
those NT domains... 

<P> Oh what the heck, here's a bonus tip: Samba works on Solaris too, so you
can have that Solaris box talk to NT boxen.  You could use *both*...

<P>
<STRONG>
sir i would be very gr8ful to u if u give me some suggestions as soon 
possible because i have to submit this assignment after 2 days.
</STRONG>

<P> The Answer Gang does not promise anybody any answer at all, timely or
otherwise.  If we do, we can publish them on the Linux Gazette website.  
THE ANSWERS WILL BE ABOUT LINUX.  Tell your friends we are not a college 
study group.



<HR NOSHADE WIDTH="40%" ALIGN="center"> <!-- ************************************** -->

<H3 ALIGN="center">Loans</H3>

<p align="right"><FONT COLOR="#000000"><strong>Answered By Ben Okopnik
</strong></FONT></p>

<STRONG>
Dear Sir:
Please send infor on how to apply for a student loan.
</STRONG></P>

<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Ben]

<OL>
<LI> Get the paperwork.
<LI> Using a #2 pencil, fill it out.
<LI> Submit it to the proper agency.
</OL>

<P> Hint: If you don't learn to spell the word "information" properly, you  
won't be able to apply for a number of the available courses, 
especially in the field of computing. <EM>Verbum sapienti</EM>, eh?




<HR NOSHADE WIDTH="40%" ALIGN="center"> <!-- ************************************** -->

<H3 ALIGN="center">Pagers</H3>

<p align="right"><FONT COLOR="#000000"><strong>Answered By Heather Stern
</strong></FONT></p>

<STRONG>
I need some basic information on how pagers work. I would appreciate it if you 
could help me out by showing me some links on the related subject, or by mailing 
me any diagram or .pdf file containig any information about it. Thanks a lot.
</STRONG></P>

<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Heather]

They work just like cellphones, except that they don't eat as much, so 
when they are on their lunch break, they get to hang out by the coffee
for a bit longer.  They like that because they can catch the local buzz.

<P> Honestly, the reason they don't eat as much is usually because the cell
phones regularly "ping" their cell site to make sure they don't have
to negotiate a handoff in order to keep listening, while pagers are
usally passive and they get whatever signal they get.  So they only 
use a tiny amount of juice to remember messages they already recieved,
and to ding or buzz or whatever it is they do.  

<P> Two way pagers may act more like cellphones, and some cellphones are
definitely pagers too, so beyond this, you need to hit the web searching
on the model number.  Some even let you web browse but even there, you 
are still not close to Linux.  See the search engines, using the keyword
"WAP" for more about that stuff.

<P> Try "how pagers work" in google?



<HR NOSHADE WIDTH="40%" ALIGN="center"> <!-- ************************************** -->

<H3 ALIGN="center">The TAG skirmish</H3>

<p align="right"><FONT COLOR="#000000"><strong>Answered By Ben Okopnik, Heather
Stern, Jim Dennis and Iron
</strong></FONT></p>

Sudhakar An asked:
<STRONG>
Gazette's July issue was pretty interesting. Jim I
assume you literally had a quarrel with Ben heh?
</STRONG></P>

<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Ben]
Yeah... he got in a fairly good lick with that bullwhip, but I'm pretty
fast with the nunchucks. We'll both be out of the hospital in no time at
all; the No-Holds Barred Smackdown rematch is already sold out, we're
both making a fortune on the t-shirts and the pre-printed mousepads, and
the crowds are screaming for blood.

<P> I've *heard* that there are people that can disagree and remain 
friends... but I'm sure that it's a myth; "Death before Dishonor", I 
always say.

<P> &lt;laugh&gt; I'm _very_ interested in how you see The Answer Gang, 
Sudhakar. You must have quite a colorful imagination.

<P>
<STRONG>
ps: Cool it Jim
</STRONG>

<P> Hey, Jim *is* cool. Just because we try to kill each other in the ring 
doesn't mean we can't be the best of friends at other times, right?

<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Heather] 
Hey, I thought we agreed, no mousepads unless you send a few to his Mom...

<P>
<STRONG>
But my problem started when I enabled services like
ftp,telnet, ssh , .... under xinetd.
</STRONG>

<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Jim]  
Yes... I can promise you that you will. We've seen lots of complaints 
about it here.

<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Heather]
And it's Ben in the ring, the Answer Guy himself Jim Dennis takes off
his wizard cap to much cheering, and ... xinetd gets in the first swing.
Zowie!

<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Ben]
(Psst - hey, Jim! I bet my t-shirt sales are higher than yours: I'm
giving away a Genuine Ben Okopnik autograph <EM>and</EM> a set of Ginsu knives
with each one!)


<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Heather]
Yeah?  I bet I can actually SELL Ginsu knives to these people!  It's got
g_n_u in it after all... half the donations to LinuxFund!  So, you wanna
bet on just the tshirts, or the whole kaboodle?

<P> btw, most geeks have plenty of tshirts.  Plus hats and the occasional change
purse.  Maybe we should sell something they *don't* usually get, like the 
rest of the wardrobe :)
<ul>
<li> belts
<li> kilts (with fashionable antispam safety pin.)
<li> togas
<li> tennis shoes (they should *definitely* give these out at Comdex)
</ul>


<P>
<STRONG>
Rgds Jim , I can understand that you guys dont mean to
be killing each other. Just seemed so real this
quarrel.
</STRONG>

<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Iron]
What was the original quarrel people keep on talking about?  Not the
"Dash it All! Coping with ---Unruly--- Filenames" thread?  That's not
quarreling, that's just having fun.


<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Ben]
I have no idea - I looked through the last ish and could find no signs 
of quarrels, arrows, or darts flung in anger or even irritation - but 
I'm sure having a ball with it. :)




<HR NOSHADE WIDTH="40%" ALIGN="center"> <!-- ************************************** -->

<H3 ALIGN="center">The finger and the Internet oracle</H3>

<p align="right"><FONT COLOR="#000000"><strong>Answered By Iron, Nick Moffitt, Heather Stern and Ben Okopnik
</strong></FONT></p>

Anonymous Coward asked:
<STRONG>
I have a question about the "finger" option on telnet.  I know that you can
find out when someone has logged in by entering "finger name" But I was
wondering if it possible to find out who has tried to finger your e-mail
account??
</STRONG></P>


<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Iron]
The short answer: 

<P> If you are the sysadmin, you can run "fingerd" with the "-l" option to
log incoming requests; see "man fingerd".  Otherwise, if you have Unix
progamming experience, it *may* be possible to write a script that logs
information about the requests you get.  If you're merely concerned
about security, the correct answer is to turn off the "fingerd" daemon
or read the "finger" and "fingerd" manpages to learn how to limit what
information your computer is revealing about you and about itself.
However, you have some misconceptions about the nature of "finger" which
we should also address.

<P> The long answer:

<P> "finger" and "telnet" are two distinct Internet services.  "http" (WWW)
and "smtp" (sending e-mail) are two other Internet services.  Each
service is completely independent of the others.  

<P> Depending on the command-line options given and the cooperation of the
remote site, "finger user@host" may tell you: 

<P> (1) BASIC USER INFORMATION: the user's login name, real name,
terminal name and write status, idle time, login time, office location and
office phone number. 

<P> (2) EXTENDED USER INFORMATION: home directory, home phone number, login
shell, mail status (whether they have any mail or any unread mail), and the
contents of their "~/.plan" and "~/.project" and "~/.forward" files.

<P> (3) SERVER INFORMATION: a  ``Welcome to ...'' banner which also shows some
informations (e.g. uptime, operating system name and release)--similar to what
the "uname -a" and "uptime" commands reveal on the remote system.

<P> Normally, ".plan", ".project" and ".forward" are regular text files.
".plan" is normally a note about your general work, ".project" is a note
about the status of your current project(s), and ".forward" shows
whether your incoming mail is being forwarded somewhere else or whether
you're using a mail filter (it also shows where it's being forwarded to
and what your mail filter program is, scary).

<P> I've heard it's possible to make one of these files a named pipe
connected to a script.  I'm not exactly sure how it's done.  (Other TAG
members, please help.)  You use  "mkfifo" or "mknod -p" to create the
special file, then somehow have a script running whose standard output
is redirected to the file.  Supposedly, whenever "finger" tries to read
the file, it will read your script's output.  But I don't know how your
script would avoid a "broken pipe" error if it writes when there's
nobody to read it, how it would know when there's a reader, or how the
reader would pass identifying information to the script.  Each Internet
connection reveal's the requestor's IP, and if the remote machine is
running the "identd" daemon, one can find out the username.  But how
your "finger" script would access that information, I don't know, since
it's not running as a subprocess of "finger", so there's no way for
"finger" to pass it the information in environment variables or
command-line arguments.  

<P> However, "finger" is much less useful nowadays than it was ten years
ago.  Part of this is due to security paranoia and part to the fact
that we use servers differently nowadays.

<P> (1) Re security, many sysadmins have rightly concluded that "finger" is a
big security risk and have disabled "fingerd" on their servers, or enable it
only for intranet requests (which are supposedly more trustworthy).  Not only
is the host information useful to crackerz and script kiddiez, but users may
not realize how much information their revealing.

<P> (2) Re how we use servers, in 1991 at my university, we had one Unix
computer (Sequent/Dynix) that any student could get an account on.
Users were logged in directly from hardwired text terminals, dialup or
telnet.  You could use "finger" to see whether your friends were logged
in.  Since you knew where your friends normally logged in from, you had
a fair idea where they were at the moment and could meet them to hack
side-by-side with them or to read (Usenet) news or to play games
together.  (Actually, you didn't even need to use "finger".  "tcsh" and
"zsh" would automatically tell you when certain "watched" users logged
in and out.) You could even use "w" to find out which interactive
program they were currently running.  But soon demand went above 350
simultaneous users, especially when the university decided to promote
universal e-mail use among its 35,000 students and 15,000 staff.  The
server was replaced by a cluster of servers, and every user logging in
to the virtual host was automatically placed on one of the servers at
random.  Since "finger" and "w" information--as well as the tcsh/zsh
"watch" service--are specific to a certain server, it was a pain to
check all the servers to see if your friends were on any of them.  About
this time, people started using X-windows, and each "xterm" window would
show up in "finger" as a separate logged-in user.  Also, finger access
became disabled outside the intranet.  "finger" became a lot less
convenient, so it fell into disuse.

<P> (3) "finger" only monitors login sessions.  This includes the "login"
program, "telnet", "xterm", "ssh" (and its insecure cousins "rsh" and
"rlogin").  It does not include web browsing, POP mail reading, irc or
interactive chat, or instant messaging.  These servers *could* write
login entries, but they don't.  Most users coming from the 
web-browser-IS-my-shell background never log in, wouldn't know what to
do at the shell prompt if they did log in, don't think they're missing
anything, and their ISPs probably don't even have shell access anyway.
That was the last nail in the coffin for "finger".

<P> So in short, "finger" still works, but its usefulness is debatable.
Linus used to use his ".plan" file to inform people of the current
version of Linux and where to download it.  SSC used to use it to
propagte its public PGP key.  There are a thousand other kinds of 
useful information it could be used for.  However, now that everybody
and his dog has a home page, this ".plan" information can just as easily
be put on the home page, and it's just as easy (or easier for some
people) to access it via the web than via "finger".


<P> <EM>Nick Moffitt asks another question, and somehow these two threads
tie together.  Then one of the Gang (whose name fell off this message)
suggested:</EM>

<P>
In this case it'd be wickedly apropos to twist finger to doing
what you want... so you can give some poor telnet-using sap "the
finger" as it were.


<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Iron]
And Nick would enjoy doing it, too.

<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Nick]
Hahaha!  Sheesh, I write a single TAG mail, and up crops
Heather Stern, Mike Orr, and Don Marti.  You folks should become the
next innurnet oracle!

<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Ben]
&lt;aghast&gt; You mean we're NOT? &lt;/aghast&gt;	
	
<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Heather]
My caffeine must be a quart low... since I was pretty sure that we must be -
otherwise we wouldn't get stupid highschooler homework questions, who 
invented the cardboard box, and driving instructions for spaceships who were
dumb enough to install NT service packs just because their code-morphing
technology was able to do that.  

<P> We could probably come up with some cute database-generated silly answer
to give instead of "These Aren't The Droids You're Looking For" but I think
we're okay for now.

<P> Except we might use postgresql instead of oracle... 
&lt;grin duck and run!&gt;

<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Ben]
&lt;glaring&gt; <EM>I</EM> managed to restrain myself.

&lt;grin&gt;

<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Iron]
Just making Linux a little bit more fun.	


<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Nick]
<EM>[In his signature:]</EM>


	
<PRE>
-- 
You are not entitled to your opinions.
</PRE>

<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Iron]
Typical Moffittism.

<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Nick]
<PRE>
	01234567 <- The amazing* indent-o-meter! 
        ^	    (*: Indent-o-meter may not actually amaze.)
</PRE>




<HR NOSHADE WIDTH="40%" ALIGN="center"> <!-- ************************************** -->

<H3 ALIGN="center">Backward compatibility of PC architecture</H3>

<p align="right"><FONT COLOR="#000000"><strong>Answered By Ben Okopnik</strong></FONT></p>

Iron asked:
<STRONG>
Yes, but *why* is this assbackwards architecture by far the most popular
computer on the market?  BECAUSE of the backwards compatibility.
</STRONG></P>


<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Ben]

Yes, but "backward compatibility" does not have to mean "keeping every 
single piece of old garbage". Once we reached the 
processing power of 486DX100s, emulating DOS for complete backward 
compatibility was a real option - and redesigning the architecture from 
the ground up while still maintaining backward compatibility was a 
reasonable goal. That was, erm, a few years ago.




<HR NOSHADE WIDTH="40%" ALIGN="center"> <!-- ************************************** -->

<H3 ALIGN="center">Squid</H3>

<p align="right"><FONT COLOR="#000000"><strong>Answered By Faber Fedor and Iron</strong></FONT></p>

Asdi Dera wrote to Faber Fedor:
<STRONG>
thank you very much for your ram disk tutorial..
my squid run very fast. ;)
</STRONG></P>

<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Iron]
Maybe if you use a helicopter you can catch up to it. :)



<HR NOSHADE WIDTH="40%" ALIGN="center"> <!-- ************************************** -->

<H3 ALIGN="center">Intrigues</H3>

<p align="right"><FONT COLOR="#000000"><strong>Answered By Ben Okopnik and Iron</strong></FONT></p>

<EM> Answering some question, Ben said:</EM>

<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Ben]
I *have* found how to make it happen again, though.


<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Iron]
He's got just enough information to make him dangerous.  We'll have to
take care of...  Oh, hi Ben.  [laughs innocuously]  I didn't realize
you were here.


<P>
<IMG SRC="../gx/dennis/bbub.gif" ALT="(!)"
	HEIGHT="28" WIDTH="50" BORDER="0"
	> [Ben]
&lt;muttering while slowly backing into a corner&gt; There is no Cabal. There 
is no Cabal. There is no... AAAAAAAHHHH!!!! &amp;)_*&amp;%$%$#LOST CARRIER













<a name="spam"></a>
<P> <hr> <P> 
<!--====================================================================-->

<center><H3><font color="maroon">World of Spam</font></H3></center>

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

<P> Hi! How are you?

<P> I send you this file in order to have your advice

<P> See you later. Thanks

<BLOCKQUOTE><EM>
	[The Answer Gang got hit with some twenty copies of the Sir Cam
	worm/virus in two days.  Finally, we added the following stanza to
	all our .procmailrc's:
	
	</EM><PRE>
:0B
* (I send you this   file in order to have your advice|\
Te mando este   archivo para que me des tu punto de vista)
/dev/null
</PRE><EM>
	
Which sends it to the great bit bucket in the sky, where it belongs.
Remove the extra spaces in the middle of the sentances.  They are just
to keep <I>LJ</I> from being deleted by any overzealous spamfilter.
The second text line is a Spanish version we also received.  Of course,
since most of the Gang doesn't read mail on Windows, we didn't have to
worry about damage, just about the amount of disk space those buggers
take up.  Sir Can attaches a file to the message.  It's a different file
each time, but usually at least 200 KB.  That means five of them take up
an entire megabyte.  LG's spamfile this month was a whopping
</EM>55 megabytes (!)<EM>, mostly due twenty more copie of this virus.
	
	-Iron.]
</EM></BLOCKQUOTE>


<HR NOSHADE WIDTH="40%" ALIGN="center"> <!-- ***************************** -->

<P> Have you been considering upgrading your web site for e-commerce or
upgrading your existing shopping cart program to a higher level of performance?
Many on-line retailer's success or failure is determined by their e-commerce
solution.  


<HR NOSHADE WIDTH="40%" ALIGN="center"> <!-- ***************************** -->

<P>  It sounds like we have some things in common. We are both 
interested in getting people to join our Internet businesses.
Recently I found some FREE promotional software that I thought 
you might also like to try out. 


<HR NOSHADE WIDTH="40%" ALIGN="center"> <!-- ***************************** -->

From: igsys <BR>
Subject: the Nigeria/African money scam emails<BR>

<P> Just to add some emails from where they sent me this scam, as mr. Justin
Catterall  
<A HREF="../issue66/lg_backpage66.html">explained</A> in issue66 these are
really bad people, they are efficient and have things well, well planned. Have
a look below at their initial response which i did on purpose  (fortunately i
had read LG issue66) to get some more emails like XXXXX  (adb stands
for African Development Bank which is a "real" african bank...), this email is
from http://XXXXX

<P> i have been using Linux since 98, keep the excelent work of Linux Gazette.
ps.: please do not publish my email for security reasons

<BLOCKQUOTE>
From: isaacson jaide<BR>
Subject: send the application and call immediately to confirm<BR>

<P> I get your mail these morning because,since i sent you
the last lether,my mind have not find any rest.

<P> I'm very happy about your possitive interest in these
business.
Regarding to what it should be used for?
what i know is that i'm going to invest mine over
there in your contry.
Please do as directed.
The letter below is what you are going to fill your
correct a/c No and full address of the Bank and send
it directly to the Foreign Exchange managers e-mail
address: adb@XXXXX.org

<P> When you send it you confirm to me that you have done
that and send a copy to me.

<P> I wait to hear from you<BR>
yours<BR>
Isaacson shakas.


<PRE>
The Manager
African Development Bank.
Johannesburg.
South-Africa.

APPLICATION FOR THE RELEASE OF THE 126MILLION IN THE
A/C NO 202-15689-1.

Reference to the above quoted A/C No. 202-15689-1 of
Late Andreas B. Smith, with credit balance of 126
Million Point Zero - Zero US Dollars Only.

As the bonafide next of kin to the above named late
Andreas B. Smith Holder of the dormant Ref A/C, we
wish to apply for the release of the total said mount
and initial part payment of $26, 000,000.00, (Twenty
Six Million US Dollars only). in our favour
representing first phase payment from the credit
balance in the said a/c.

In accordance with National and International Laws of
inheritance kindly remit the stated amount in full to
our a/c No quoted below:

(PLEASE ENTER YOUR BANK DETAIL HERE)

This request is predicated on the fact that since the
death of our Manager Mr. Andreas B. Smith who was
entrusted with The Management of KRUGER GOLD MINING
CO. The need for the transfer of the money in the
account becomes imperative.

We shall therefore be very grateful if this request
meets with your favourable consideration


Thanks

Yours faithfully,
(YOUR FULL NAME)
</PRE>
</BLOCKQUOTE>


<HR NOSHADE WIDTH="40%" ALIGN="center"> <!-- ***************************** -->

I am interested in speaking with you about powering career centers for your
online properties.  XXXXXXXXXXX is the largest network of I.T. specific Job
Posting Sites.  The following URL will link you into a detailed description
of all of XXXXXXXXXXX's Network Partners and their corresponding Homepages
and XXXXXXXXXXX Career Centers.  See revenue splits below.  Career Centers
are fully customized to your specifications and are implemented at No Cost
Whatsoever.  
 
 <P>
Our standard revenue share structure is as follows:<BR>
-You Receive 100% of banner ad revenues realized from the career center(avg.
40 imp/user)<BR>
-50/50 split on spotlight job advertising<BR>
-50/50 split on job posting received trough your sites<BR>

<BLOCKQUOTE><EM>
	[And banner ads are SOOO lucrative!  -Iron.]
</EM></BLOCKQUOTE>


<HR NOSHADE WIDTH="40%" ALIGN="center"> <!-- ***************************** -->

<P> Valerie XXXX, a patient of dentist and hypnotherapist Dr. Bruce XXXXXXXX,
was trained to use hypnosis to see into the future and discovered an
undiagnosed medical problem that threatened the mother's (Joann's) life.



<HR NOSHADE WIDTH="40%" ALIGN="center"> <!-- ***************************** -->

<P> Are you looking for your first Internet business...or your last?  

<P> If it's your first, wouldn't you like it to be your last?  Your last should
be like going home....it should be the one that allows you to double your full
time income on a part time basis, is stable, will be there for your heirs, and
give you the lifestyle you dream of.




<HR NOSHADE WIDTH="40%" ALIGN="center"> <!-- ***************************** -->

<P> Listen, you don't have to tell me - I KNOW what your experiences 
have been marketing online. You've been in one of two places. EITHER 
you're fairly new on the Internet, and you KNOW that SOMEBODY 
makes money online - but you can't quite figure out HOW. OR MAYBE 
you can "sign people up" like gangbusters - and those people just 
SIT THERE. Those people don't just "sit there" because they are "lazy",
 "stupid" or "don't have the desire". The ONLY way for this to work is 
to do what is done in EVERY OTHER industry but ours - and that is, 
let the "marketers" do the "marketing" - and let the other people do 
what THEY do best!

<P>
 Some people just STINK at marketing. And they will NEVER
make money online -no matter which "HOT! NEW!" thing they jump
into again THIS week! But the thing is - you don't HAVE to! Want to 
find out why I market for OTHER PEOPLE all day? Then you 
need to see my open letter about HOW we do that. Just a word to the 
wise. LOTS of people do it our way. Want to FINALLY make money 
online? Want to NEVER have to "recruit" and "motivate" and "babysit" 
again? Then see how YOU can succeed online even if you HATE to 
market! WHY IN THE WORLD would you NOT want us to do the 
marketing FOR you? Are you having such GREAT success trying to 
do it on your own? Are your people? Let US set up a totally 
AUTOMATED system for you where WE do all the marketing for 
you and we ALL make money!!

<BLOCKQUOTE><EM>
	["Or your last" ... because so many people are getting out of the
Internet business! -Iron.]
	</EM></BLOCKQUOTE>

<HR NOSHADE WIDTH="40%" ALIGN="center"> <!-- ***************************** -->

Update Your Income Now!

<BLOCKQUOTE><EM>
	[That's it, I want to get an income upgrade.  -Iron.]
</EM></BLOCKQUOTE>






<HR NOSHADE WIDTH="80%"> <!-- ************************************** -->

<P> Happy Linuxing!

<P> Mike ("Iron") Orr<br>
Editor, <A HREF="http://www.linuxgazette.com/"><i>Linux Gazette</i></A>, <A
HREF="mailto:gazette@ssc.com">gazette@ssc.com</a>
<BR CLEAR="all">

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<P> <hr> <P> 
<H5 ALIGN=center>
Copyright &copy; 2001, the Editors of <I>Linux Gazette</I>.<BR>
Copying license <A HREF="../copying.html">http://www.linuxgazette.com/copying.html</A><BR>
Published in Issue 69 of <i>Linux Gazette</i>, August 2001</H5>
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