...making Linux just a little more fun!


This month's answers created by:

[ Sayantini Ghosh, Amit Kumar Saha, Ben Okopnik, Joey Prestia, René Pfeiffer, Neil Youngman, Rick Moen, Thomas Adam ]
...and you, our readers!

Still Searching

Reg:Postfix mail redirection

Smile Maker [britto_can at yahoo.com]

Tue, 1 Jul 2008 00:10:15 -0700 (PDT)


If I have got mails which does not contain <MydomainName > in the from address which is sent to some aliases should get "redirected" to my account.

Any idea..

-- Britto

Getting started with Linux & OLPC

Ben Okopnik [ben at linuxgazette.net]

Mon, 14 Jul 2008 11:10:02 -0400

[[[ I've changed the subject line from the undescriptive "can u help...." -- Kat ]]]

----- Forwarded message from nick zientarski <nick81z@hotmail.com> -----

From: nick zientarski <nick81z@hotmail.com>
To: editor@linuxgazette.net
Subject: can u help....
Date: Mon, 14 Jul 2008 02:16:57 -0400

i bought an OLPC "give one/get one" computer, well...4 total, one for my mother and I...we need a little help with getting started on the linux system... the more i read about this open source way to compute gets me more and more excited, it is just a little much starting out...any resources or service companies i could mail to start our new relationship with linux..we would be more than greatful thank you for your time :) ~nick zientarski~

----- End forwarded message -----

Our Mailbag

Averatec n40bers and sy0b3es

Tony Davis [tdavis803 at bellsouth.net]

Sat, 19 Jul 2008 14:49:37 -0400

Sirs i have a averatec 5400 and when i try to type something i get this get n40bers and sy0b3es What is wrong


Tony Davis

the only way i can type anything is to hold down a fn key

[ Thread continues here (2 messages/1.33kB) ]

inquiry on tcpdump

Ignacio, Domingo Jr Ostria - igndo001 [DomingoJr.Ignacio at postgrads.unisa.edu.au]

Tue, 1 Jul 2008 13:24:03 +0930

Hello everyone,

Good day!

I am using tcpdump in my linux system to sniff and capture tcp packet headers.

I inserted a new variable, srtt, into the print_tcp.h header file and tcp.c source code. I want to print/ouput/capture the inserted variable srtt into the tcp packet headers once I run tcpdump. Any idea on how to go about this?

However, once I run tcpdump with all the changes I made (of course, after configuring and making) and I got an error: Bad header length and <bad opt>.

I tried to increase the snaplength to 1514 but I still got the same errors. What seems to be the problem, anyone? Thanks!

Also, I cannot see the inserted srtt variable in the tcpdump trace files. Any idea on these guys?

I don't know if this is the right venue to ask these question since this is for linux queries but still I am hoping that anyone has an experience on this. Help would be appreciated.

Cheers, Dom

[ Thread continues here (5 messages/5.48kB) ]

[OT] Nagware from Google Translate

Jimmy O'Regan [joregan at gmail.com]

Tue, 15 Jul 2008 16:18:52 +0100

I was trying to point a friend of mine to http://librivox.org today, and for some reason he couldn't connect to it. The quickest way of finding a proxy he could use was via Google Translate (he's Polish). When I looked at the page, however, I say that the phrase 'some free software' (in refernce to open source software, such as Audacity) had become 'niekt√≥re wolne oprogramowanie *rejestrujące*' - 'some registered free software' - which makes me wonder if Google's next service will be nagware.google.com :)

[ Thread continues here (2 messages/1.47kB) ]

SMTP Auth Problem

Joey Prestia [joey at linuxamd.com]

Sat, 05 Jul 2008 09:28:38 -0700

Hi all,

I am administering a e-mail server running RHEL 5 with sendmail 8.13 and using dovecot imap most of the users are going to need to be able to send mail from their laptops and i have no idea what network they will be utilizing. After looking at http://www.joreybump.com/code/howto/smtpauth.html and following the guide there I was able to get authenticated relay enabled.

I am using saslauthd and never created sasl passwords but following the guide at http://www.joreybump.com/code/howto/smtpauth.html was able to get it working. now after 6 months of no problem and then the other day changed my password to a stronger one now I cannot relay from anywhere.

[root@linuxamd ~]# sasldblistusers2
listusers failed
[root@linuxamd ~]#
[root@linuxamd ~]# testsaslauthd -u joey -p ******
0: NO "authentication failed"

is this my problem?

All accounts are stored in /etc/passwd saslauthd is running and I performed a restart of saslauthd with out any errors.

I have tried with both kmail and thunderbird. My usual settings are tls if available and and smtp auth with username and password I thought at first that this was the problem it was using the old password so I removed the default smtp server settings and removed the passwords. So it would force me to manually enter the password again I did this while on another network and tried to send with no success. As soon as I disconnected from the neighboring lan and connected to the local lan it took and sent but I am unsure if it is using auth it seems like it is only sending because its on my lan how would I verify the authentication process is working at all? I am not certain exactly how saslauthd works and have seen nothing unusual in my logs. Thunderbird simply times out when I try to send from other networks and tells me to check my network settings.

Thanks in advance,

Joey Prestia
L. G. Mirror Coordinator
Main Site http://linuxgazette.net

[ Thread continues here (18 messages/42.62kB) ]

Regular Expressions

Deividson Okopnik [deivid.okop at gmail.com]

Thu, 17 Jul 2008 23:50:11 -0300

Quick regular expressions questions, I have a string and i want to return only whats inside the quotes inside that string - example the string is -> "Deividson" Okopnik <-, and i want only -> "Deividson" <-. Its guaranted that there will be only a single pair of double-quotes inside the string, but the lenght of the string inside it is not constant.

Im using PHP btw



[ Thread continues here (13 messages/16.08kB) ]

What other existing RMAIL Emacs commands or techniques or mechanisms are useful for sorting out spam messages?...

don warner saklad [don.saklad at gmail.com]

Mon, 30 Jun 2008 08:50:57 -0400

For nonprogrammer type users what other existing RMAIL Emacs commands or techniques or mechanisms are useful for sorting out spam messages more efficiently and effectively?... for example in RMAIL Emacs laboriously sorting out spam messages can be tried with Esc C-s Regexp to summarize by: ...

For nonprogrammer type users it appears that using existing commands for each session is an alternative to attempts at composing programs or tweaking others' programs or the difficulties of dotfiles.

C-M-s runs the command rmail-summary-by-regexp
as listed on the chart
C-h b describe-bindings
          Key translations:
          key             binding
          ---             -------
          C-x           Prefix Command
          C-x 8         iso-transl-ctl-x-8-map
          Major Mode Bindings:
          key             binding
          ---             -------
          C-c           Prefix Command
          C-d           rmail-summary-delete-backward
          RET           rmail-summary-goto-msg
          C-o           rmail-summary-output
          ESC           Prefix Command
          SPC           rmail-summary-scroll-msg-up
          -             negative-argument
          .             rmail-summary-beginning-of-message
          /             rmail-summary-end-of-message
          0 .. 9                digit-argument
          <             rmail-summary-first-message
          >             rmail-summary-last-message
          ?             describe-mode
          Q             rmail-summary-wipe
          a             rmail-summary-add-label
          b             rmail-summary-bury
          c             rmail-summary-continue
          d             rmail-summary-delete-forward
          e             rmail-summary-edit-current-message
          f             rmail-summary-forward
          g             rmail-summary-get-new-mail
          h             rmail-summary
          i             rmail-summary-input
          j             rmail-summary-goto-msg
          k             rmail-summary-kill-label
          l             rmail-summary-by-labels
          m             rmail-summary-mail
          n             rmail-summary-next-msg
          o             rmail-summary-output-to-rmail-file
          p             rmail-summary-previous-msg
          q             rmail-summary-quit
          r             rmail-summary-reply
          s             rmail-summary-expunge-and-save
          t             rmail-summary-toggle-header
          u             rmail-summary-undelete
          w             rmail-summary-output-body

[ Thread continues here (3 messages/4.45kB) ]

kernel inquiry

Ignacio, Domingo Jr Ostria - igndo001 [DomingoJr.Ignacio at postgrads.unisa.edu.au]

Thu, 3 Jul 2008 16:51:39 +0930

Hi guys,

In the tcp.h header file , I found the variables:

#define TCPOPT_WINDOW			3
#define TCPOPT_SACK			5

Does anyone can help me with what the numbers 3,5,8 means? Are they the tcp option numbers in the TCP header? Or are they port definitions?

Cheers, Dom

[ Thread continues here (3 messages/4.94kB) ]

Tool to populate a filesystem?

René Pfeiffer [lynx at luchs.at]

Wed, 16 Jul 2008 23:46:06 +0200


I am playing with 2.6.26, e2fsprogs 1.41 and ext4, just to see what ext4 can do and what workloads it can handle. Do you know of any tools that can populate a filesystem with a random amount of files filled with random data stored a random amount of directories? I know that some benchmarking tools do a lot of file/directory creation, but I'd like to create a random filesystem layout with data, so I can use the usual tools such as tar, rsync, cp and others to do things you usually do when setting up, backuping and restoring servers.

Curious, René.

[ Thread continues here (13 messages/24.92kB) ]

Multi-host install of FC6

Ben Okopnik [ben at linuxgazette.net]

Wed, 16 Jul 2008 17:22:12 -0400

Hi, all -

I'm going to be teaching a class next week in which the student machines are going to have Fedora Core 6 installed on them, so the poor on-site tech guy is going to be spending his weekend flipping the 6 installation CDs among a dozen-plus machines - not a happy-fun thing at all, as I see it.

Does anyone know of a way to set up an "install server" for FC6? Perhaps I've been spoiled by the Solaris 'jumpstart' system, where you set up a simple config file, tell your hosts to load from the jump server, and walk away - but I can't help feeling that anything Solaris can do, Linux can do better. :)

* Ben Okopnik * Editor-in-Chief, Linux Gazette * http://LinuxGazette.NET *

[ Thread continues here (11 messages/12.45kB) ]

Auto detect and mount SD Card

kanagesh radhakrishnan [rkanagesh at gmail.com]

Thu, 24 Jul 2008 12:30:31 +0530


I am working on an ARM based custom development board that has a Micro SD connector.

I use Linux (kernel version 2.6.24) on the board and I have support for the Micro SD cards. The SD driver has support for hotplug. At the bash prompt on the target board, I am able to mount the card, write data to it and read data from it. What utility do I need to add to the root file system for the card to be detected automatically when it's inserted and the file system on the card's media to be mounted to a specified mount point?

A couple of years ago, I was working with PCMCIA Flash memory cards and USB memory disks. There used to be a utility called Card Manager (cardmgr) that detects the insertion of a PCMCIA flash memory card and mounts it automatically. USB memory disks used to be automounted by the hotplug scripts. Is there any utility similar to this for SD/MMC/Micro SD cards?

Thanks in advance, Kanagesh

[ Thread continues here (2 messages/1.90kB) ]

SCP Sensing Remote file presense

Smile Maker [britto_can at yahoo.com]

Tue, 22 Jul 2008 04:28:11 -0700 (PDT)


When you do scp to remote machine, linux assumes to overwrite the target file if exists. Is there any way to check whether the target file exists and then copy the actual file.

--- Britto

[ Thread continues here (3 messages/2.04kB) ]

asking about MIB structure of SNMP agent running on various type of Solaris, HP-UX and Windows

Mulyadi Santosa [mulyadi.santosa at gmail.com]

Wed, 9 Jul 2008 17:03:12 +0700

Hello gang!

As the subject says, I have hard times understanding the result of snmpwalk against those platforms. Not that I can't query those nodes, but snmpwalk is unable to translate the numeric form of OID into human readable string label.

More precisely, I need to find the MIB files that describe the returned SNMP data. So far, my best bet is by referring to oidview.com, but the MIB files I have downloaded from this site don't always work as expected i.e some OIDs are still in numeric form, thus I don't whether it refers to disk usage, cpu utilization and so on.

I will highly appreciate any inputs regarding this issue.



[ Thread continues here (8 messages/10.32kB) ]

is it possible to make CUPS daemons cooperate between themselves?

Mulyadi Santosa [mulyadi.santosa at gmail.com]

Wed, 9 Jul 2008 17:26:55 +0700

Hi gang...

Sorry if the subject sounds confusing, but I wonder, is it possible? AFAIK, each CUPS daemons manage its own queue on the node's own disk...and by design I don't see CUPS is designed as cooperative daemon.

By "cooperative" I mean something like having unified print spool, unified and shared printer device's name among CUPS daemons...and so on.

Looking forward to hear any ideas about it...



[ Thread continues here (7 messages/6.96kB) ]

thanks for CUPS tips

Mulyadi Santosa [mulyadi.santosa at gmail.com]

Thu, 24 Jul 2008 08:24:38 +0700

Hi all

Just wanna say big thanks for your suggestions when I asked about CUPS configuration days ago. it works quite nicely in my environment.

I know I haven't share much for LG but you answered my question faster than my close colleagues/partner. I highly appreciate that. You guys really do something valuable in your free time.

God bless!



Followup: US sanctions-compliant Linux

Simon Lascelles [simon.lascelles at rems.com]

Thu, 3 Jul 2008 11:17:08 +0100

I would like to thank everyone for their comments. I do hope the topic has not made too many peoples blood pressure to rise to "dangerous levels", although it is clear a topic several people are passionate about. In summary it looks to me that Linux could be used on one of two basis's;

1. If we were not a UK company (or any company citied in the restrictions). To resolve this we could establish an off shore company to provide the distribution to circumvent this restriction.

2. Encryption was removed from the package. A task I believe is relatively simple to achieve.

Two points I would like to make for your information and further comment is that I believe the restriction on US content is 10% not 1% as one person commented. Secondly I will of course seek legal advice before proceeding but wanted to see if this issue had been seen before, by the experts (the legal guys don't tend to know what they are talking about anyway). Thank you once again and if you have further advice on the issue it would be gratefully appreciated.

Simon Lascelles 
Managing Director
REMS International
Email: simon.lascelles@rems.com <blocked::mailto:simon.lascelles@rems.com> 
Web Site: http://www.rems.com/ <http://www.rems.com/> 
Mobile: 07956 676112
Telephone: 01727 848800; 
Yahoo: rems25x8@yahoo.com

Mobile communications are changing the face of business, and organisations that deploy mobile solutions will reap the greatest competitive advantage


[ Thread continues here (2 messages/4.38kB) ]

Searching for multiple strings/patterns with 'grep'

Amit k. Saha [amitsaha.in at gmail.com]

Thu, 3 Jul 2008 16:46:41 +0530

On Mon, Jun 23, 2008 at 5:11 PM, Ben Okopnik <ben@linuxgazette.net> wrote:

> On Mon, Jun 23, 2008 at 11:52:44AM +0530, Amit k. Saha wrote:
>> Hello TAG,
>> I have a text file from which I want to list only those lines which
>> contain either pattern1 or patern2 or both.
>> How to do this with 'gre'p?
>> Assume, file is 'patch', and 'string1' and 'string2' are the two patterns.
>> The strings for me are: 'ha_example' and 'handler'- so I cannot
>> possibly write a regex for that.
> Over the years, I've developed a working practice that says "don't use
> grep for anything more than a simple/literal search." Remembering the
> bits that you have to escape vs. those you don't is way too much of a
> pain. Stick with 'egrep', and you don't have to remember all that stuff.
> ``
> egrep 'string1|string2' filepattern

hmm. Works great.


Amit Kumar Saha
Skype: amitkumarsaha

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Published in Issue 153 of Linux Gazette, August 2008