Weblog

LinuxTag in Berlin is over now and I think it was a great event. There is so much diverse and interesting stuff happening in the free software scene and the conference did a very good job at showing this clearly.

This year I was speaker (slides) as well as helper for the OpenEmbedded booth. From my personal rating my talks did not went so well. It would have been easy for me to cope with a slight fatigue, the technical problems (my Fedora9-powered iBook refused to detect the beamer connection, Sebastian's laptop could only show a clipped part of the slides) and do the talk in my mother's language. However I insist on being international-friendly (I would not like attending a foreign conference and have only talks in a language I do not understand.) and therefore did it in English. Well, that is the part where I have to try harder. :-)

Sebastian and me really missed Guillaume from MIDPath fame! It would have been a great opportunity to show everyone the really cool advancements of his project. Unfortunately work interferred and made him cancel the talk. Later we decided that I will jump in and present his slides so there would be no gap in the program. This did not went so well either: The MIDPath talk was 2 hours after mine and fatigue increased. Additionally it became clear that I am not so versed with all those J2ME technologies. Well, anyone who is interested in the project should not base his/her opinion on my presentation abilities but get in contact with Guillaume and the project's subversion repository. :)

On the other hand I think my booth attendance went very good. There where a lot of people showing up and asking questions. I find it much more easy to give answers that way (regardless of language).

An exciting happening for me was to meet and talk to Rob Savoye. He is currently developing Gnash and was one of the founding members of Cygnus Support. Cygnus was the first company making money from selling support services for free software and for this they (Rob and everyone else at Cygnus) are my personal heroes. They made this business model acceptable and I am convinced that their activities made my (and many others') free software job today possible. For this I am very thankful!

The companies' founding was in 1987 and still today you find people in the FOSS movement who confuse free software and earning money. I also like Cygnus' slogans: "We make free software affordable", "If its not source, its not software". So great! And remember that those slogans where coined before Linux was developed.

Oh yes, I really enjoyed talking to Rob. There are people who have less coding skills and experience than him and appear snobbish or affected. Not so with Rob. I felt being treated very kind regardless of me having difficulties with language again. :-D

What was also great that I together with Mario Behling had the chance to make an interview with Harald 'LaForge' Welte of gpl-violations.org and netfilter/iptables fame. We talked about the former project and company attitude towards the GNU GPL. I hope that with the publication of the interview more people get to know about Harald's (and the Freedom Taskforce's) work.

In my opinion free software developers should have a basic understanding of copyright, license requirements (share-alike/copyleft) and know the difference between copyright and patent law (bonus points if you also grok trademark law). You can learn all this from websites, Wikipedia and by reading Larry Lessig's 'Free Culture'. As such it only costs time and dedication and among other things tremendously helps making non-gossip comments over things happening at debian-legal. ;-)

This blog post is becoming to long and I have not talked about all the topics that interested me. Tomorrow I will write about who else I met at LinuxTag and those really cool things in the embedded free software scene I can't keep my mouth shut any longer. :-)

As the title says I like scripts and many other people like them, too. In package management systems there are four of them which are especially important, namely prerm, postrm, preinst and postinst.

The maven-pkg-plugin which we are developing for Jalimo to ease the effort to create proper (binary) packages for various GNU/Linux distributions (as well as IzPack installer for all kinds of OSes) just learned to support them. This is important especially for supporting the Maemo platform because according to their guide you have to restart a certain system service after installation.

Here is the output of such a script which is now part of our example application jalimo-swt-example2: 

Nokia-N800-44-4:~# dpkg -i  debs/jalimo-swt-example2_0.1.0-0maemo_chinook-r2_all.deb 
Selecting previously deselected package jalimo-swt-example2.
(Reading database ... 15719 files and directories currently installed.)
Unpacking jalimo-swt-example2 (from .../jalimo-swt-example2_0.1.0-0maemo_chinook-r2_all.deb) ...
Hello user! This is the pre-install script talking.
We are dealing with maemo_chinook distribution. Possibly better
known as Maemo 4.0 (Chinook). It uses the deb package
management system.

You can use the following variables:
prefix=/
bindir=/usr/bin
datadir=/usr/share/jalimo-swt-example2
datarootdir=/usr/share
sysconfdir=/etc
jnidir=/usr/lib/jni
bundledjardir=/usr/share/java/jalimo-swt-example2
version=0.1.0-0maemo_chinook-r2
name=jalimo-swt-example2
mainClass=org.jalimo.examples.swt.SwtExample2

Isn't this great?

Same script different distribution:

root@fic-gta01:~$ ipkg install jalimo-swt-example2_0.1.0-0openmoko-2007.11-r2_all.ipk 
Upgrading jalimo-swt-example2 on root from 0.1.0-0openmoko-2007.11 to 0.1.0-0openmoko-2007.11-r2...
Hello user! This is the pre-install script talking.
We are dealing with openmoko-2007.11 distribution. Possibly better
known as OpenMoko 2007.11. It uses the ipk package
management system.

You can use the following variables:
prefix=/
bindir=/usr/bin
datadir=/usr/share/jalimo-swt-example2
datarootdir=/usr/share
sysconfdir=/etc
jnidir=/usr/lib/jni
bundledjardir=/usr/share/java/jalimo-swt-example2
version=0.1.0-0openmoko-2007.11-r2
name=jalimo-swt-example2
mainClass=org.jalimo.examples.swt.SwtExample2

Isn't this great?

The packaging plugin got vastly improved in the last weeks. IMHO the most important bit is, that it can distinguish between distributions: For the plugin at makes a lot of difference if you want your package to run on Debian Etch or Debian Lenny. The latter contains a lot more Java packages and therefore it tries to make use of them (if there is no package for a specific Maven artifact it will automatically bundle this) which means putting the package name into the dependency list and adding it to the application's classpath.

For this to work the plugin contains a built-in Maven2 artifact (= single jar file) to target distribution package mapping. In the earlier version of the plugin there was only one definition of such mapping, now it supports any number. Also system properties, additional files (including the above mentioned scripts), the main class and many more can be set on a per distribution basis.

The plugin also knows the distribution's packaging system, of course. Finally you can add/modify your own distribution mapping without the need to recompile the plugin. Still some basic information about Maemo Chinook, Debian Etch and Lenny as well as OpenMoko 2007.11 is already provided.

What is additionally nice is that Maven2 itself got packaged for Lenny. :-)