Removing unwanted applications in Debian

One of the biggest pitfalls for a new Debian (or Linux) user is attempting to remove an unwanted application than came installed with the Desktop installed. This can result in the Debian package manager informing the user that there are various packages which can be autoremoved. Allowing the package manager to autoremove these packages then removes packages essential to the Desktop environment, destroying the installation. Why?

In Linux, one package can depend on another. For example, A depends on B. If you install A, the package manager will automatically install B, because it is required. If you uninstall A, the package manager will tell you B is autoremoveable, unless you have installed another package which also depends on B.

If you uninstall B,  A's dependency will be missing and it will not work, so the package manager will want to uninstall it.

Desktop environments are installed using a metapackage, which is simply a list of packages to install. A depends on B,C,D,E,F,G.... If you want to uninstall F, A's dependencies will not be met, so the package manager will want to uninstall it, and the rest of your desktop environment- not what you want, or even expect: B for example may work quite happily even if F is not present.

What is the solution?

In the past I've used apt-mark to unmark packages for autoremoval. This works, but a recent thread on the Debian forum made me aware that it's not an ideal solution.

An explanation of the Debian package management system and metapackages then appeared on the Forum. It gives a detailed example of how to remove one application from a metapackage and correct the autoremove marking of wanted packages in the metapackage.

HOWTO: How I learned to stop worrying and love metapackages

It is a rather complicated procedure, so advice for a Linux novice might be, don't be tempted to remove applications you don't need from a desktop environment, or if you do, don't remove packages marked as autoremove.

Life with eternal upgrades- first casualty

An update to Audacious in Debian Jessie (Testing) means it fails to start. It looks like the plugins and some of the libraries used by Audacious need to be updated.

WARNING: Audacious seems to be already running but is not responding.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Transport/neon.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Transport/unix-io.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Transport/mms.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Input/sid.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Input/amidi-plug.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Input/vorbis.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Input/cdaudio-ng.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Input/vtx.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Input/modplug.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Input/ffaudio.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Input/flacng.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Input/adplug.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Input/madplug.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Input/wavpack.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Input/console.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Input/tonegen.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Input/xsf.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Input/psf2.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Input/sndfile.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Input/aac.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Input/metronom.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Output/sdlout.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Output/jackout.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Output/filewriter.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Output/null.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Output/alsa.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Output/pulse_audio.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Output/oss4.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Effect/ladspa.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Effect/resample.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Effect/crystalizer.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Effect/crossfade.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Effect/sndstretch.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Effect/echo.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Effect/bs2b.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Effect/stereo.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Effect/compressor.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Effect/mixer.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Effect/voice_removal.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/General/song_change.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/General/mtp_up.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/General/aosd.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/General/gnomeshortcuts.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/General/gtkui.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/General/lirc.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/General/statusicon.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/General/scrobbler.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/General/notify.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/General/search-tool.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/General/skins.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/General/albumart.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/General/mpris2.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/General/hotkey.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/General/alarm.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/General/lyricwiki.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/General/cd-menu-items.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Visualization/cairo-spectrum.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Visualization/blur_scope.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Container/xspf.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Container/m3u.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Container/cue.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Container/asx.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Container/audpl.so is not compatible with this version of Audacious.
 *** ERROR: /usr/lib/i386-linux-gnu/audacious/Container/pls.so is not compatible with this version of Audacious.
FATAL: No output plugin found.

Update: there's a bug report for this.

Scrolling text: Jacq's Blogger Tips.

Can't update Iceweasel from Experimental on Jessie

I use the Debian Experimental repository to update Iceweasel to the latest Firefox release version provided by the Debian Mozilla team.

Trying to update to Iceweasel 21 produces this message:

Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 iceweasel : Depends: xulrunner-21.0 (>= 21.0-1) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

Very similar to a similar problem I had in Wheezy.

Trying to install xulrunner-21.0 produces this message:

The following packages have unmet dependencies:
 xulrunner-21.0 : Depends: libc6 (>= 2.15) but 2.13-38 is to be installed
                  Depends: libmozjs21d (= 21.0-1) but it is not going to be installed

libc6 seems to be the issue, as it is currently not available in Experimental and the version in Testing is 2.13 as reported.

Edit: Fixed the title. Cut and pasted from a previous post but forgot to change Wheezy to Jessie.

SolydXK Forums have also noticed the problem.

Update Flash fix security flaws! (Again)

Flash has been updated to fix security vulnerabilities.

This is not an automatic update for Debian users (see here). To update, issue this command:

# update-flashplugin-nonfree --install

Life with eternal upgrades

I have switched my Debian sources to Testing, aka Jessie. The Debian Reference has a good page on Testing:

Despite my warnings above, I know many readers of this document wish to run the testing or unstable suites of Debian as their main system for self-administered Desktop environments. This is because they work very well, are updated frequently, and offer the latest features.

!Caution For your production server, the stable suite with the security updates is recommended. The same can be said for desktop PCs on which you can spend limited administration efforts, e.g. for your mother's PC. 

 It takes no more than simply setting the distribution string in the "/etc/apt/sources.list" to the suite name: "testing" or "unstable"; or the codename: "wheezy" [now Jessie] or "sid". This makes you live the life of eternal upgrades.

The use of testing or unstable is a lot of fun but comes with some risks. Even though the unstable suite of Debian system looks very stable for most of the times, there have been some package problems on the testing and unstable suite of Debian system and a few of them were not so trivial to resolve. It may be quite painful for you. Sometimes, you may have a broken package or missing functionality for a few weeks.

This is not a work computer (or "production machine" as they are described more grandly), I have my trusty Crunchbang Live USB handy, and I am willing to put up with a bit of pain.

I used Wheezy Testing for several months before the freeze and had no major problems, but maybe the cascade of new packages now Testing has been unfrozen will be a different experience. I'm looking forward to the fun!

Windows sucks more

 

I was asked to look at a laptop that kept shutting down. My first thought was a dirty fan and overheating, but it seemed to be a software issue, with Google Chrome crashing followed by a system shutdown, and warning from an installed program on reboot. The desktop had also turned black.

I noticed that in a corner of the screen Windows was saying it wasn't genuine, but the user said the computer was from a major PC store and had the original OS. I suspected a virus or hard disk corruption was causing the shutdown, but of course, as readers more familiar with Windows may realise, I was barking up the wrong tree.

After investigating my original suspicions for several hours, I did what I should have done at the beginning and looked at the logs in Control Panel > System and Maintenance > Administrative Tools > Event Viewer, and one of them very kindly told me that Windows was shutting down every hour because it was not genuine.

In the meantime, I had discovered that the hard drive was corrupted. The user had just replaced the battery, so probably the laptop had shutdown improperly after the power supply was pulled out. However, although Windows told me that the disk had errors, the chkdsk would not run on reboot.

I eventually discovered a solution: hit F8 while booting, select Repair Your Computer, click on Command Prompt and enter chkdsk /f :C (or whatever the name of the problem disk is).

My best guess is that chkdsk was not working from Windows because some system files had become corrupted. A nice Catch 22.

I'd tried entering the Windows key to activate Windows, but it hadn't been accepted. I began to suspect that some corrupt system files were also preventing the activation process. (sfc /scannow reported corrupt files but couldn't fix them- another nice Catch 22 to be in- system files are corrupt, but they can't be repaired, because system files are corrupt...)

The computer owner had recently had the screen replaced and used a driver update utility. A web search suggested that new hardware or drivers can cause Windows to report it is not genuine. None of the solutions I came across worked, I'm pretty sure because of the damaged system files, but I found a patch for pirate copies of Windows that disables Windows activation. After several hours of trying to fix the problem, I applied the patch, and the computer worked normally. OK so applying an illegal patch is not the ideal solution, but I was looking at the computer as a favour and several more hours work reinstalling the OS didn't appeal.

I returned the laptop and was very glad to get back to Linux.

Debian Wheezy released

Debian

I've been using Wheezy for months (as Testing), and found it very stable. Of course, I am now faced with what I've previously called the Linux dilemma:  whether to stick with the stability of Wheezy for two years, or switch to a more cutting edge release or distro to experience the latest software updates, and risk experiencing a few bugs. Wheezy is already out of date: Gnome 3.4, XFCE 4.8 and kernel 3.2- and Wheezy is not going to see feature updates for two years.