Saturday, March 12, 2016

Virtualbox on arch linux kernel 4.4.5

Since my last upgrade to latest packages of arch linux including kernel 4.4.5 I had trouble starting virtualbox.

[user@xxxxx ~]$ sudo /sbin/rcvboxdrv setup           Unloading modules:  Loading modules: modprobe: ERROR: could not insert 'vboxnetadp': Exec format error
modprobe: ERROR: could not insert 'vboxnetflt': Exec format error
modprobe: ERROR: could not insert 'vboxpci': Exec format error
modprobe: ERROR: could not insert 'vboxdrv': Exec format error
Here are the steps I took to make the trouble go away:
  • reboot to make the new kernel 4.4.5 active
    • sudo shutdown -r now
  • reinstall linux-headers (use the correct version for your kernel!): this triggered a recompile of the virtualbox kernel modules by dkms
    • sudo pacman -S linux-headers
  • remove package virtualbox-host-modules: this removed old pre-compiled vbox kernel modules. In retrospect, it was probably this last step that actually solved the problem.
    • sudo pacman -R virtualbox-host-modules
For what it's worth :)

Friday, August 21, 2015

Microsoft Random Limitation Rant

Welcome in 2015, the era of Multi-GHz Clocks, Multi-GB RAM, PetaByte storage and... 260 character path names.

Once again I was bitten by yet a random path length limitation on a win 7 64-bit platform with visual studio 2013. Of course I am aware that longer path lengths are supported on current windows platforms, provided you do some "\\?\" hocus pocus but Microsoft basically admits it's too much magic for them, given that they won't fix the random limitations embedded in their own build tools and just prefer to let hundreds (probably thousands) of developers bump into them.

Don't believe me? Read the giant's own website for more details and weep :)

More info about using long path names:

Monday, August 11, 2014

Why did flash player stop working in chromium on Debian?

Adobe flash is evil right? Yet many sites insist on using it (who knows for what evil purpose?!) and it's annoying the heck out of me if they keep throwing warnings about a missing flash player. 

Well, here's a clue: somehow I missed the news that chrome/chromium now uses a google maintained version of flash player which you can install using 
apt-get install pepperflashplugin-nonfree
Nothing to see here really. Carry on :)

Sunday, June 8, 2014

problems encountered while switching to systemd

Computer stopped booting

After the latest dist-upgrade in debian SID my system refused to boot. After seemingly doing nothing for a while my computer would just drop into an emergency root console. In the mean time everything is up and running again, and here's what I had to do to make it boot again:

  • After reading many bug reports and forum entries about NFS mounts in fstab causing a system not to boot, I decided to take a look at my /etc/fstab. In /etc/fstab I had specified (amongst other things) mount points for cdrom, dvd, and up to two usb sticks:
/dev/cdrom /media/cdrom0 udf,iso9660 user,noauto 0 0
/dev/dvdrw1 /media/dvd auto noauto,rw,user,exec 0 0
/dev/sdb1 /media/usbstick auto users,rw
/dev/sdc1 /media/usbstick2 auto users,rw
After commenting out all those lines, the system suddenly booted again. Despite the "missing" entries, KDE still manages to recognize USB sticks and while it might be unrelated, I noticed that now suddenly KDE is able to correctly play audio CDs -- something I had never managed before. The player would start but I never got any sound from it.

CUPS refused to start

Once the system booted again I hit the next problem: I couldn't print anymore since CUPS refused to come up. After searching the net, I saw more people having the same problem. In a lucky guess I looked in /etc/sysctl.conf and saw a line:

net.ipv6.conf.all.disable_ipv6 = 1

I disabled that line and cups worked again! I then added that information to a bug record related to bringing up CUPS on systemd . In the mean time other people have encountered the same issue:

No visual feedback during boot

This was the least of my problems initially, but after a while I missed the coloured OK's during startup.
Turns out /etc/default/grub contained a line


after changing that to


and running update-grub, my beloved colored OK's are back :)


All systemd versus SysVinit wars aside, I haven't seen other issues on my system so far. Keeping fingers crossed :)

Sunday, March 9, 2014

Getting rid of "What's hot and recommended" in your google plus stream

1. go to[]
2. click the explore link on the top of the page
3. click the "what's hot" link in the "Explore google+" blue thingy that appears
4. click the cogwheel in the red "What's hot and recommended" thingy that appears
5. uncheck "show posts in home stream"

Friday, August 2, 2013

can Pyjamas rise from its ashes?

As a quick follow-up to my article about pyjamas being hijacked, there's an interesting blog article (in French) pointing out the existence of a new incarnation of the original Pyjamas project set up by Luke Leighton at According to that blog article this new initiative was sparked by Goffi, the author of the blog article.

Given that the hijacked project, while it has seen some contributions from different people, seems to have slowed down considerably since the debacle (although it's possible that people are developing awesome stuff in their forks), I'm curious to see what this intiative - if anything - will do to make pyjamas more popular again.

Here are two screenshots comparing the recent git histories.

recent git history of the hijacked project at

recent git history of the reinstated pyjamas at