A KDE 4 small overview This speech illustrates some of the major KDE4 features. Slides are shorts since has been made for a “wiki-night” :)

I was surprised the news that Microsoft announced UOF-OpenXML translator project with China. The goal of UOF–OpenXML translator :

"As part of Microsoft’s continued commitment to interoperability, Microsoft decided to work with CHINA Electronics Standardization Institute, Beijing Information Technology Institute, one of the co-creators of the UOF Chinese standard , Beihang University of Beijing and with other partners to create a Translator between UOF and Open XML and provide interoperability between the two formats in both directions. Microsoft is funding and providing technical architectural guidance for the development of the translator that will benefit millions of people who live in China."

I’m really honored to report that dot.kde.org has published the english translation of my interview for kde-it. You can find it here.

Finally the wanted entry: I started running again. We had Murph the dog with us. He had to stop every now and then and forced us to stop as well (phew).

Schließt man einen USB-Joystick an hat openSUSE ein recht merkwürdiges Verhalten. Zumindest gilt dies für meinem Fall, bei dem ein Logitech Extreme 3D Pro an ein Asus Motherboard mit nForce 570 SLI-Chipsatz angeschlossen wird. Auf dem System läuft openSUSE 10.2 x86_64. Zum Glück lässt sich diese Problem mit wenigen Handgriffen lösen.

Zunächst scheint das System den Joystick korrekt zu erkennen, was unter anderem anhand von dmesg zu sehen ist.

marix@eddie:~> dmesg | grep Joystick
input: USB HID v1.10 Joystick [Logitech Logitech Extreme 3D Pro] on usb-0000:00:02.0-1
input: USB HID v1.10 Joystick [Logitech Logitech Extreme 3D] on usb-0000:00:02.0-4

Wie zu sehen ist habe ich gleich zwei Joysticks angeschlossen. Zunächst schein aber alles zu funktionieren.

Interessant wird die Sache sobald man versucht den Joystick zu verwenden. Started man zum Beispiel das hervorgagende D1X-Rebirth bekommt man eine wenig erfreulich Meldung.

sdl-joystick: found 0 joysticks

Bestätigt wird die schlechte nachricht auch beim Einsatz von joy2key.

Error opening /dev/input/js0!
Are you sure you have joystick support in your kernel?

Wie die Meldung vermuten lässt, liefert ein ls /dev/input/ | grep js nichts zurück. Der Joystick funktioniert zwar als USB-Gerät, aber seine Semantik ist unbekannt.

Die Fehlermeldung von joy2key führt zur Lösung. Um den Joystick auch unter /dev/input zu sehen muss das Kernelmodul joydev geladen werden.

eddie:~ # modprobe joydev

Damit dies auch bei jedem Systemstart automatisch geschieht muss eine zeile in /etc/init.d/boot.local eingefügt werden.

/sbin/modprobe joydev

Nun steht der Joystick auch bei jedem Systemstart sofort zur Verfügung.

Nun zur Kuriosität. Startet man YaST und installiert neue Software funktioniert der Joystick anschließend reproduzierbar auch so. In diesem Fall scheint aus irgendeinem Grund das Modul also immer geladen zu werden. Sieht fast so aus, als wären Joysticks leider nicht mehr verbreitet genug um von Anfang an berücksichtigt zu werden und wurden beim Startup einfach vergessen.

I’m really honored to report that KDE-Italy site published an interview about me. You can find it here. Many thanks to Giovanni Venturi, webmaster and maintainer of kde-it.org!

Mouse speaking. Back from Australia. Was familiar to me. They should offer me new travel opportunities. It's getting a bit boring. They didn't even let me fight with the redback. At least I look more and more audacious with all the smears of dirt on my face. Antje in the meanwhile attended this cookery course and now she cooks strange stuff. I suspect she just doesn't do it properly. She told me that they had fits of cough while doing the course. She believes it was due to the amount of chili. I rather think they are just incompetent. And the poor visitor who just wanted to have a quick dinner nearly fainted over his meal. On Saturday I had to drink ouzo again. At least Antje got us some wine gums after the pub visit. It took her a while to win the fight against the sweets machine though.

One of the reasons I wanted to revive rcd was so that I could use it to play with some package management ideas I’ve been kicking around. One of these ideas is a way to reliably rollback changes made during an RPM transaction. That is, actually make RPM transactions transactional.

Recently, a colleague introduced me to device-mapper, a kernel system used for block device redirection. There is a really cool thing that uses it called dm-snapshot, which allows you to redirect all writes to a device into a separate device. What I would like to do is use this to store all of the changes made during an rpm transaction. I think it would just need a bit of patching so that it only stores the changes made by the rcd/rpm process (and children). If anything goes wrong, you can just trash the snapshot data and things are exactly as they were in the beginning. Of course, if it succeeds without problelms, you need to merge the snapshot changes into the original device. This is where things get fuzzy, as dm-snapshot does not have this ability. However, Mark McLoughlin has created a set of patches that add this feature as part of the Stateless Linux project. Sadly, the patches do not appear to be a high priority for the kernel guys right now, so I guess this approach will have to be put on hold.

In any case, a system for performing this rollback stuff would be ridiculously useful in general — not just for package management. It looks like it will be a little more than I can do by myself in a weekend hack, though, so hopefully someone else will carry the torch? :)

Thanks to everyone who told me about the rpmdb backup in /var/adm/backup/rpmdb - I restored it and now everything is working beautifully.

Yesterday my computer started randomly rebooting when I was trying to install packages on my computer, so I booted from a live CD and ran resierfsck on my disk, which fixed a whole bunch of things. But now when I run rpm -qa I get a list of no packages - and running rpmdb --rebuilddb doesn't help. Fortunately smart query lists everything that is installed, so I'm pretty sure there must be some way to get the rpmdb back, but I can't find it. Help!