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<H4>"Linux Gazette...<I>making Linux just a little more fun!</I>"
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<H1><A NAME="tips"><IMG ALIGN=MIDDLE ALT="" SRC="../gx/twocent.gif">
More 2&#162; Tips!</A></H1> <BR>
Send Linux Tips and Tricks to <A HREF="mailto:gazette@ssc.com">
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<a name=""></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Getting the most from multiple X servers - in the office and at home
</FONT> </H3>
Fri, 19 May 2000 10:31:27 +1000
<BR>From: Bob Hepple &lt;<A HREF="mailto:bhepple@bit.net.au">bhepple@bit.net.au</A>&gt;
<P> I wonder how many people know how to get the most from the power of X -
it really sets Unix apart from simple windowing PC's. Here is a tip that
I've been using for years - maybe it will be news to others as it's not
really documented anywhere for the average user, it's rather buried in
the man pages.
<P> To set the scene, poor old dad often has to stand aside to let the rest
of the family read their email, do their homework etc. This is a bit of
a fag on certain well known proprietary windowing systems as you would
have to
<P> save your work
exit all applications,
log out,
let them play through,
log them out,
log back in
restore all applications
<P> Rather than do all this, I simply create a new X session with the
following command:
<P> X :1 -query raita &amp;
<P> where 'raita' is the name of my computer. A new X server starts up and
the visitor can log in and do their stuff. We can flip between their
session and my own with Ctrl-Alt-F8 and -F7. When they are finished,
they simply hit Ctrl-Alt-BackSpace or log out and I warp back to my own
workspace with Ctrl-Alt-F7.
<P> No loss of data, no messy loging in and out.
<P> You need to be running an XDMCP session manager (e.g. xdm, gm or kdm)
for this to work. You are using XDMCP if you get a graphical logon at
bootup. If you have a text-mode logon and run X with startx then you
might need to modify this approach.
<P> I also use this neat feature of X at work - we have many Unix systems
that I need to log into from time to time - Linux, Solaris and UnixWare.
I could use rlogin, rsh or xrsh but for some jobs nothing beats a full X
session.
<P> I can flip from one system to another by creating new X sessions on my
Linux workstation. Normally at work I use a slightly modified command:
<P> X :1 -indirect dun &amp;
<P> ... where dun is runnning an XDMCP server (like xdm, gdm or kdm). It
then gives me a chooser that I can use to pick which system to log into.
<P> I often have many such sessions at once - just increment the display
number for each and they map to different 'hotkeys':
<P> X :1 -indirect dun .... Ctrl-Atl-F8
X :2 -indirect dun .... Ctrl-Atl-F9
X :3 -indirect dun .... Ctrl-Atl-F10
<P> with Ctrl-Alt-F7 being the default X display :0
<P> Another ploy is to use Xnest in a similar way. Instead of getting an
extra X server, Xnest runs a new X session in a window. I use this:
<P> Xnest :1 -indirect dun &amp;
<P> or, if I want to use a full-sized screen I use:
<P> Xnest -geometry 1280x1024+0+0 :1 -indirect dun &amp;
<P> There are some minor issues with font sizes when using a smaller window
but generally not too bad.
<P> <hr> <P>
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<a name=""></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Starting and stopping daemons
</FONT> </H3>
Fri May 26 16:13:11 PDT 2000
<BR>From: Mike Orr &lt;<A HREF="mailto:mso@mso.oz.net">mso@mso.oz.net</A>&gt;
<P> If you get tired of typing "/etc/init.d/apache reload" every time
you change your Apache configuration, or if you frequently start and stop
squid (e.g., to free up memory for extensive image editing), use
shell functions to take the tedium out of typing.
<P> The following functions allow you to type "start daemon", "stop daemon",
"restart daemon", and "reload daemon" to accomplish the same thing. They
should work on Debian or a
similar system which has a script for each daemon in
<STRONG>/etc/init.d/</STRONG>, where each script accepts
<STRONG>start</STRONG>, <STRONG>stop</STRONG>, <STRONG>restart</STRONG> and
<STRONG>reload</STRONG> as a command-line argument.
<P> I used <CODE>zsh</CODE>, so I put the following in my
<STRONG>/root/.zshrc</STRONG>:
<PRE>
function start stop restart reload { /etc/init.d/$1 $0 }
</PRE>
This creates four functions, each with an identical body. $0 is the command
name (e.g.; "start"); $1 is the first argument (the name of the daemon).
<P> The equivalent functions in
<CODE>bash</CODE> look like this:
<PRE>
function start { /etc/init.d/$1 start; }
function stop { /etc/init.d/$1 stop; }
function restart { /etc/init.d/$1 restart; }
function reload { /etc/init.d/$1 reload; }
</PRE>
<CODE>bash</CODE> puts "-bash" into $0 instead of the command name.
Perhaps there's another way to get at the command name, but I just chose to
make four functions instead.
<P> Debian actually puts the name of the package in
<STRONG>/etc/init.d/</STRONG>; this may be different than the name of the
daemon. For instance, the <CODE>lpd</CODE> daemon comes from a package
called <STRONG>lprng</STRONG>. An enhancement to the functions would be
to recognize <STRONG>lpd</STRONG>, <STRONG>lpr</STRONG> and <STRONG>lp</STRONG>
as synonyms for the easily-forgotten <STRONG>lprng</STRONG>.
<P> <hr> <P>
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<a name=""></a>
<H3><IMG ALIGN=BOTTOM ALT="" SRC="../gx/lil2cent.gif">
<FONT COLOR="navy">Disabling the console screensaver
</FONT> </H3>
Fri May 26 16:13:11 PDT 2000
<BR>From: Jim Dennis &lt;<A HREF="mailto:jimd@starshine.org">jimd@starshine.org</A>&gt;
<P> Shane Kennedy &lt;<A HREF="mailto:skenn@indigo.ie">skenn@indigo.ie</A>&gt;
asked the Answer Guy:
<BLOCKQUOTE>
How do I switch off the shell screensaver?
</BLOCKQUOTE>
<PRE>
setterm -blank 0
</PRE>
<P> It's a feature of the Linux console driver, not the
shell.
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<H4><font color="maroon">
Tips in the following section are answers to questions printed in the Mail
Bag column of previous issues. These tips were compiled with help from
<A HREF="mailto:iamalsogod@hotmail.com">Michael Williams</A> (Alex).
</font></H4>
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<hr>
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<p align="center">&nbsp;</p>
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<p><img src="../gx/lil2cent.gif" width="126" height="51">
<a
name="kernelsplit"><font color="#000080"><strong>Linux Kernel Split</strong></font></a></p>
<p>Thu, 04 May 2000 08:34:09 -0500<br>
From: Christopher Browne &lt;<a href="mailto:cbbrowne@hex.net">cbbrowne@hex.net</a>&gt;<br>
<br>
<br>
This can refer to to things:<br>
<br>
a) The fact that Linux kernel releases are split into
&quot;stable&quot; and &quot;experimental&quot; releases.<br>
<br>
Thus, versions numbered like 1.1.n, 1.3.n, 2.1.n, 2.3.n represent
&quot;experimental&quot; versions, where addition of new
functionality is solicited, whilst those numbered 1.0.n, 1.2.n,
1.4.n, 2.0.n, 2.2.n, 2.4.n represent &quot;stable&quot; versions,
where changes are intended to only be made to fix problems.<br>
<br>
Occasionally, &quot;experimental&quot; functionality gets
backported to the &quot;stable&quot; releases, but this is not
the norm.<br>
<br>
b) There is a theory that, at some point, development of Linux
could &quot;split&quot; to multiple independent groups.<br>
<br>
For instance, there are some people working on functionality
intended to support big servers (e.g. - SMP, various filesystem
efforts). And there are others building functionality supportive
of tiny embedded systems (Lineo, Embeddix, ...)<br>
<br>
The theory essentially goes that since their purposes are
different, there may be some point at which the needs may diverge
sufficiently that it will not make sense for there to be a single
point of contact (e.g. Linus Torvalds) to decide the direction of
development of _THE_ official<br>
Linux kernel.<br>
<br>
What might happen is that a group would take a particular version
of the Linux kernel source code, and start developing that quite
independently of another.<br>
<br>
For instance, there might be a &quot;split&quot; where the
embedded developers start developing the kernel in a way attuned
to their needs.<br>
<br>
This is _essentially_ what happened when OpenBSD
&quot;split&quot; off of the NetBSD project; the developers
concluded that they could not work together, and so a new BSD
variant came into being.<br>
<br>
The use of the GNU General Public License on the Linux kernel
does mean that it would be legally permissible for a person or a
group to perform such a &quot;split.&quot; <br>
<br>
It would, however, be quite _costly_, in that it would mean that
the new group of developers would no longer have much benefit
from the efforts of people on the other side of the split. It is
a costly enterprise (whether assessed in terms of money, or,
better, time and effort) to keep independent sets of source code
&quot;in sync&quot; once they are purposefully taken out of sync.<br>
<br>
Hope this helps provide some answers to the question...</p>
<p align="center">&nbsp;</p>
<hr>
<!--================================================================-->
<p align="left"><img src="../gx/lil2cent.gif" width="126"
height="51"> <a name="128ram"><font color="#000080"><strong>Incorrect
Tip....</strong></font></a></p>
<p align="left">Date: Sat, 13 May 2000 15:57:49 -0400<br>
From: Tony Arnett &lt;lkp@bluemarble.net&gt;<br>
<br>
Tip given on Linux systems that do not recognize the total
almount of available ram.<br>
<br>
The tip given was to insert the following param into
&quot;lilo.conf&quot;<br>
<br>
<strong>append=&quot;ram=128M&quot;</strong><br>
<br>
I had no such luck with this param. I think the proper param to
use is:<br>
<br>
<strong>append=&quot;mem=128M&quot;</strong><br>
<br>
This worked for me on my Gentus Lunux 1.0 System.<br>
<br>
Here is my entire<font color="#FF0000"> <strong>lilo.conf</strong></font><br>
<br>
<br>
<strong>boot = /dev/hda<br>
timeout = 50<br>
prompt<br>
default = linux<br>
vga = normal<br>
read-only<br>
map=/boot/map<br>
install=/boot/boot.b<br>
image = /boot/vmlinuz-2.2.13-13abit<br>
label = linux<br>
initrd = /boot/initrd-2.2.13-13abit.img<br>
root = /dev/hda5<br>
append=&quot;hdc=ide-scsi hdd=ide-scsi mem=128M&quot;<br>
other = /dev/hda1<br>
label = win</strong><br>
<br>
<br>
I hope this will help someone.<br>
<br>
Lost Kingdom Productions<br>
Tony Arnett<br>
<br>
<!--============================Editor=============================--></p>
<blockquote>
<p><em>[It is definitely </EM><CODE>append=&quot;mem=128M&quot;</CODE></EM> as you
say. I use it myself. The only instance of &quot;ram=&quot; I
could find was in </em><a
href="http://www.linuxgazette.com/issue44/tag/46.html"><em>http://www.linuxgazette.com/issue44/tag/46.html</em></a><em>,
and it is quoted in part of the question, not as the answer.
If there are any other places where it says
&quot;ram=128M&quot;, please let me know where and I'll fix
them immediately.<br>
<br>
I looked in the Bootprompt-HOWTO </em><a
href="http://www.ssc.com/mirrors/LDP/HOWTO/BootPrompt-HOWTO.html"><em>http://www.ssc.com/mirrors/LDP/HOWTO/BootPrompt-HOWTO.html</em></a><em>
and did not see a &quot;ram=&quot; parameter. There are some
&quot;ramdisk_*=&quot; parameters, though, but that's a
different issue. -Ed.]</em></p>
</blockquote>
<hr>
<!--================================================================-->
<p><img src="../gx/lil2cent.gif" width="126" height="51"><font
color="#000080"><strong>Re: Command line editing</strong></font></p>
<p><font color="#000000">Wed, 17 May 2000 08:38:09 +0200<br>
From: Sebastian Schleussner </font><a
href="mailto:Sebastian.Schleussner@gmx.de"><font color="#000000">Sebastian.Schleussner@gmx.de</font></a></p>
<blockquote>
<font color="#000000">I have been trying to set
command line editing (vi mode) as part of<br>
my bash shell environment and have been unsuccessful so far. You
might<br>
think this is trivial - well so did I.<br>
I am using Red Hat Linux 6.1 and wanted to use &quot;set -o
vi&quot; in my<br>
start up scripts. I have tried all possible combinations but it
JUST DOES<br>
NOT WORK. I inserted the line in /etc/profile , in my
.bash_profile, in<br>
my .bashrc etc but I cannot get it to work. How can I get this
done? This<br>
used to be a breeze in the korn shell. Where am I going wrong?</font>
</blockquote>
<p align="left"><font color="#000000">Hi!<br>
I recently learned from the SuSE help that you have to put the
line<br>
set keymap vi<br>
into your /etc/inputrc or ~/.inputrc file, in addition to what
you did<br>
('set -o vi' in ~/.bashrc or /etc/profile)!<br>
I hope that will do the trick for you.<br>
<br>
Cheers,<br>
Sebastian Schleussner<br>
</font></p>
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This page written and maintained by the Editor of the <I>Linux Gazette</I>.
Copyright &copy; 2000, <A HREF="mailto:gazette@ssc.com">gazette@ssc.com</A><BR>
Published in Issue 54 of <i>Linux Gazette</i>, June 2000</H5>
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