People behind Debian: Martin Michlmayr, former Debian Project Leader

Martin Michlmayr is a Debian developer since 2000 and I share quite a few things with him, starting with his age and involvement in the quality assurance team. He managed to be elected Debian Project Leader in 2003 and 2004.

He’s no longer as active as he used to be but his input is always very valuable and he continues to do very interesting things in particular concerning the support of NAS devices. Read on for the details.

Raphael: Who are you?

Martin: I’m Martin Michlmayr. I’m 32, originally from Austria, and currently living in the UK.

I’ve contributed to various free software projects over the years but Debian is without doubt the one I’m most passionate about. I joined Debian in 2000 when I was a student. I worked on Debian more or less full time for a few years while I was pretending to study. Later I started a PhD to do research about quality and management aspects of volunteer free software projects. I investigated the release process in several free software projects, in particular looking at time-based releases. After finishing my PhD in 2007, I joined Hewlett-Packard. I’m part of HP’s Open Source Program Office and work on various free software and open source activities, both internally and within the community.

Raphael: How did you start contributing to Debian?

Martin: I first used Debian in the days of 0.93R6, some time around the end of 1995. The 0.93R6 release was still based on a.out but I needed an ELF-based system for some application, so I moved to Slackware. I then quickly moved to Red Hat Linux where I stayed for several years. I rediscovered Debian in 2000 and quickly decided to join the project. I cannot recall how I rediscovered Debian but when I did, it was clear to me that Debian was the ideal project for me: I could identify with its philosophy, I liked the volunteer nature of the project, and I found the size and diversity of Debian interesting since a large project offers a lot of different challenges and opportunities.

I remember how many new things there were to learn and back then the documentation and other resources for new contributors were nowhere as good as they are today. My application manager, Julian Gilbey, was a great help… he was incredibly friendly and passionate about Debian. I also remember meeting up with Peter Palfrader (weasel) for key signing when we were both in the New Maintainer queue. I was incredibly lucky with my New Maintainer process and soon became an official Debian Developer. Because there was a shortage of application managers, my first major contribution in Debian was to become an application manager myself and help other people join the project.

Debian is a large project with a long history and a rich culture, so new contributors should expect that it will take some time to become familiar with everything. Fortunately, there are many resources, such as documentation and the debian-mentors list, for new contributors. Another great way to become familiar with the way things are done in Debian is to subscribe to various Debian mailing lists and ideally to read some mailing list archives. It’s also a great idea to attend the Debian Conference or other conferences since meeting people in real life is a great way to integrate. I remember attending Debian Conference 1 in Bordeaux where I gave my first public talk.

Finally, new contributors should find an area where they can make a unique contribution. Most people in Debian maintain packages but there are so many other ways to contribute. For example, most of my contributions were not technical but were about coordination and other organizational activities.

Raphael: What’s your biggest achievement within Debian?

Martin: I’m particularly proud of a number of achievements:

  • New Maintainer: I helped a lot of people join Debian. It’s great to help someone join the project and then see how they contribute. Of course, some people join Debian and then quickly become inactive or retire… you never know in advance how it will work out. But I had the pleasure to help some truly outstanding contributors to join Debian.
  • Quality Assurance: I helped improve QA processes within Debian. In particular, I realized a few years ago that a lot of packages had maintainers who were inactive and that nobody did anything about it. I started to write to those maintainers to see what could be done. It’s hard because you don’t know the circumstance of someone… they may be inactive because of an illness or for other good reasons… so you have to be friendly, but yet persistent. Fortunately, most maintainers I contacted were truly inactive and so they couldn’t complain when I took their packages away.
  • DPL: I acted as the Debian Project Leader for two years. I’m particularly proud of this because Debian is a great project and it was an honour to represent it. I performed important organizational and coordination tasks. I also traveled to a lot of conferences and had the pleasure to meet many Debian Developers as well as users of Debian. It’s very motivating to meet users and to hear how they use Debian and how we can further improve it.
  • Debian on NAS: Debian is without the doubt the Linux distro with the best support for NAS (Network Attached Storage) devices. I was always impressed by what the OpenWRT folks have done to support wireless routers and wanted to do something similar for Debian. Unfortunately, wireless routers just don’t have enough storage for a full distro. But then NAS devices came along and they obviously have enough space since they are meant for storage.

Raphael: Speaking about NAS devices: what exactly are you doing on this topic and how can people help?

Martin: There are plenty of instructions on the Internet to install Linux distributions on NAS or various embedded devices by connecting a serial console and then typing in hundreds of commands. What I found is that such instructions significantly limit the user base because they are way too complicated for most users. There are just too many steps that can go wrong.

So instead, in Debian, we provide a solution that just works: usually, you download a firmware image for your NAS device from Debian and when you upgrade you get the Debian installer. You connect to the installer via SSH and perform a normal installation. The installer knows about the device and will prepare everything for you automatically… for example, it knows if the device has requirements for the partition layout and it will install the kernel where the device expects to find it; unfortunately, NAS devices are not like PCs, so the requirements are different for almost every device and therefore you need special code to support a new device. Finally, there are detailed installation guides and we provide help on our mailing lists.

There are a number of technical areas for improvement. The installation could be made even easier, and it would be nice to support new platforms and devices.

A bigger problem is that while we’ve implemented a great solution for NAS devices, we haven’t really extended this work to support other classes of devices. For example, tablets and mobile phones are getting incredibly popular and we don’t have a compelling solution for such devices, mostly because of the lack of an appropriate GUI.

Raphael: What are your plans for Debian Wheezy?

Martin: I’ve recently been asked by Stefano Zacchiroli, our current Debian Project Leader, to coordinate the care-taking of Debian finances. Debian, as a volunteer project, relies on donations and in-kind gifts (e.g. hardware) to maintain its infrastructure and to support various development efforts, such as funding sprints and other developer gatherings. Debian’s money and other assets are held by affiliate organizations around the world.

My responsibility will be to keep track of money and other assets (e.g. hardware and trademarks), work with the DPL to establish procedures related to the use of Debian’s assets, and make sure that the procedures are followed. Finally, we want to publish public statements so our donors know how we use their donations to further improve Debian. I just started working on this and this will be my main activity in Debian in the coming months.

Raphael: Speaking of money, I plan to run a fundraising to get the Debian book I wrote with Roland Mas translated (cf. http://debian-handbook.info). Is this something Debian should support?

Martin: First of all, I should make it clear that I don’t decide how Debian spends its money. This is up to the DPL to decide together with the project at a whole. I’ll just make sure that procedures are followed and expenses tracked and reported properly.

Having said that, in my opinion, it’s unlikely that Debian as a project will fund this effort. It would be inconsistent with the position of the project not to fund work directly (only some related expenses, such as travel costs to allow Debian teams to organize face-to-face meetings). Whether Debian should support the fundraising effort by helping to promote it is another question and that’s probably not as clear cut. It looks like a worthwhile effort, but on the other hand it would be unfair for authors of other Debian books for Debian to put its weight behind one… and there are many other efforts that are worth promoting… if you promote one, where do you stop? So while it sounds worthwhile, it’s probably better for Debian to stay out of it.

But somehow related to this, I sometimes worry about the fact that there are so few paid opportunities around Debian. If you contribute to the Linux kernel for a while, you have an excellent chance to get hired by someone and to work on the kernel full time. The kernel may be an extreme example but there are a lot of projects that have more paid opportunities than Debian, e.g. Mono, GNOME, OpenOffice/LibreOffice and KDE.

Obviously, there are some Debian Developers who can spend some time on Debian as part of their job. I know that some Canonical employees contribute to Debian, that support companies like credativ improve Debian as part of their work, and that system administrators fix bugs or package new software as they deploy Debian. But I think this is a minority of contributors and even they don’t work full time on Debian. Instead what I see is that a lot of people leave university, get a job and then no longer have time for Debian… or people start a family and no longer have time. I can take myself as an example since I don’t have nearly as much time as I did in the past when I was a student.

I guess there are different ways to deal with this problem… one would be to create more paid opportunities around Debian outside the project, another one might be to make it easier for new volunteers to join the project. I don’t have the answers to these questions… but it’s something I wonder about, and I also wonder whether pure volunteer projects can still keep up with projects with a lot of full time contributors.

Raphael: What motivates you to continue to contribute year after year?

Martin: Debian is a great project with a great mission, goals and people. I contribute to make Debian a better solution and to promote the free software philosophy. Finally, the community around Debian provides a lot of motivation. It’s amazing how much I’ve learned about other cultures because of my involvement in Debian and how many friends I’ve made over the years all around the world.

Raphael: Do you have wishes for Debian Wheezy?

Martin: Not really. I’m pretty happy with the way things are going at the moment. We have made a lot of organizational changes in the last few years from which the project has greatly benefited. I’m particularly pleased about the plans to adopt a time-based freeze.

Raphael: Is there someone in Debian that you admire for their contributions?

Martin: There are many people I admire greatly. I’d like to mention Joey Hess because he’s a great example to follow. He doesn’t get involved in politics, is easy to work with and does great technical work. In fact, he has made not one but several contributions that have completely changed Debian (debconf, debhelper, and debian-installer). Furthermore, Debian has a lot of contributors who have done great work over the years but who are not very vocal about it. People like Colin Watson or Peter Palfrader. Debian has many unique contributors and the list of people I admire is much longer than the few people I just mentioned.


Thank you to Martin for the time spent answering my questions. I hope you enjoyed reading his answers as I did. He raised some interesting questions.

Subscribe to my newsletter to get my monthly summary of the Debian/Ubuntu news and to not miss further interviews. You can also follow along on Identi.ca, Twitter and Facebook.

Deciphering one of dpkg’s weirdest errors: unable to open ‘/path/to/foo.dpkg-new’

We already studied one weird error of dpkg, let’s do another one:

Unpacking replacement libexo-common ...
dpkg: error processing /var/cache/apt/archives/libexo-common_0.6.1-1_all.deb (--unpack):
 unable to open '/usr/share/doc/exo/html/C/images/exo-preferred-applications-internet.png.dpkg-new': No such file or directory

Rather difficult to understand on the first look right? Let’s see in detail what’s usually happening when you get this error.

The first hint comes from the file extension “.dpkg-new”. This extension is used by dpkg to unpack the updated files near the old files. When everything has been unpacked, they are renamed over the old files.

The failure happens precisely when dpkg tries to rename the file (in fact when it tries to fsync() it before the rename)… but why does it fail?

Usually because there are unexpected symlinks (or bind mounts) involved that resulted in two different files being installed in the same directory. For example consider package that provides /dir1/a-file and /dir2/a-file. Now imagine that on the target system, /dir1 is a real directory but /dir2 is a symbolic link that points to /dir1.

When dpkg processes /dir1/a-file.dpkg-new everything is fine, but when it tries to process /dir2/a-file.dpkg-new it will fail because that file is the same than /dir1/a-file.dpkg-new which has already been renamed.

Diagnosing further the problem requires to understand why there’s a symlink instead of a real directory. It might be two packages that were badly coordinated, or a problem in the package itself because it lacks some code that drops the symlink in the preinst (so that dpkg installs the real directory instead of keeping the symlink).

There might be variations in the way two files end up sharing the same directory, but this simple example should have clarified the nature of the underlying problem.

Subscribe to this blog by RSS, by email or on Facebook.

How to squash Debian release critical bugs

Squashing release critical (RC) bugs is one of the most helpful way to contribute to Debian. Because those are the bugs that we need to get rid of in order to release the next stable version. Let’s see how you can help.

The process is really simple:

  1. Find a RC bug that you can fix
  2. Prepare a fixed package
  3. Send the patch to the BTS
  4. Get your fixed package uploaded

I have already covered points 2 and 3 in a former article: How to prepare patches for Debian packages. So I’m not going to repeat myself in this article, instead I’ll cover how to find a release critical bug to fix and how to get your package uploaded.

Find a RC bug with UDD

The Ultimate Debian Database (UDD) provides a neat interface to query the bug tracking system: http://udd.debian.org/bugs.cgi. The form contains many options to customize the query, we’ll try explain some.

First, at the top, you can decide to list bugs based on whether or not they affect testing/stable/unstable. Indeed, thanks to version tracking the BTS knows if a bug applies to the version of the package present in a given distribution. I suggest you pick a choice that includes “sid” because that’s where you’re going to push your fixed package. If sid is not affected by the bug, you can’t do much about it (except if you want to join the release team and help ensure updates are flowing from unstable to testing).

I usually go for “wheezy and sid” because that filters out packages which are not in testing (and are thus not blocking the next release).

Then you have lots of filters to further reduce the list of bugs. It’s important to reduce the noise as you typically have several hundreds of RC bugs at a given time. I suggest you the following settings for a start, but you’re free to try other combinations depending on what you want to achieve (I’ll give some examples later):

  • ignore bugs tagged patch (a fix is already available);
  • ignore bugs tagged pending (a fix has already been committed to the VCS repository);
  • ignore bugs newer than 7 days (that’s the time we should leave for the maintainer to take care of the bug by himself);

I usually sort the results by source package so that I immediately see if several RC bugs are affecting the source package. And I might add “popularity contest” information to get a feel of whether the package is widely used or not.

You can see the results of the suggested query here.

Other interesting queries:

Find a RC bug with rc-alert

The downside of the above method is that you get bugs on packages that you don’t know at all and that you might not care about. Some of them might even be better removed instead of fixed.

With the rc-alert command (provided by the devscripts package), you will get a list of RC bugs on packages that are installed on your computer. It should be much more restrictive. And you have command line options to further filter the list just like with the UDD form. Bonus feature: you can also filter by debtags allowing you to restrict the bugs to packages which are implemented in programming languages that you know.

$ rc-alert --include-dists TU --exclude-tags P+ --debtags implemented-in::perl,implemented-in::python
Package: gwibber
Bug:     608724
Title:   gwibber bypasses certificate checking when providing the login/password for OAuth
Flags:   [     S  ] (security)
Dists:   [STU] (stable, testing, unstable)
Debtags: implemented-in::python, interface::x11, role::program, uitoolkit::gtk, works-with::im, x11::application
[...]

Get your fixed package uploaded

Usually sending the patch to the BTS is more than enough. The maintainer or another Debian developer will pick it up at some point. But if you’re interested in becoming a Debian maintainer/developer, it might be worth to push your changes more quickly and get credited by a proper upload with your name.

Instead of just preparing a patch, you should also prepare a fixed package following the rules of a Non-Maintainer Upload. Put this package somewhere online (for example on mentors.debian.net).

When you send your patch to the BTS, include the link to the updated package and express your wish to get this update sponsored. If you haven’t heard anything from the maintainer after 2-3 days, try to find a sponsor on debian-mentors@lists.debian.org. NMUs are easier to review than completely new packages and many Debian developers like to kill RC bugs, so there’s a good chance that you’ll find someone.

Now happy RC bug-squashing! And if you really enjoy it, you can subscribe to debian-bugs-rc (~3000 mails per month)… :-)

If you want to read more articles like this one, click here to subscribe to my free newsletter. You can also follow me on Identi.ca, Twitter and Facebook.

7 tips to file useful Debian bug reports and get your problem solved

Filing bug reports is the most common way for users to contribute. Even if it’s not too difficult, I’ll give you some advice to improve the quality of your reports. After all, when you go out of your way to report a bug, it is in the hope to see it fixed… so let’s see how we can make this more likely.

1. Try to reproduce the bug

If you can’t reproduce the bug, it’s next to impossible to find the root cause and thus to fix it. In that case, I would suggest you to wait until you experienced the bug multiple times. Maybe you’ll be able to find something that triggers it (or that makes it more likely to encounter it). If the application has a debug/verbose mode, it might be a good idea to enable it until you experience the bug a second time. The generated log might be helpful for the developer to understand what happens exactly.

So don’t file bug reports straight away unless you can reproduce it. The exception to the rule is when the application gives some useful information like a core-dump, a back-trace or an error message.

Obviously if the bug happens during an upgrade, it’s difficult to reproduce it (unless you have multiple computers) but you should still report it. Be sure to include all the relevant information (versions of packages before and after the upgrade, logs of the upgrade, etc.).

2. Do your best to identify the faulty package

When you report a bug to Debian, you must assign it to a package. While there are pseudo-packages useful for problems which are not directly attributable to a real package, in most of the cases you should report a bug against the specific package that seems to be the cause of the problem you encountered.

In turn this often requires you to attribute the problem to a file (for example the executable of the application that triggers the bug). Once you have a filename you can use dpkg -S to identify the corresponding package.

$ dpkg -S /usr/bin/hamster-time-tracker
hamster-applet: /usr/bin/hamster-time-tracker

Note that reportbug accepts a filename as parameter and will do the above conversion for you.

If you only know the name of the application (but not the filename of the associated executable), you can use dpkg -S with a pattern to let it return all possible matches:

$ dpkg -S hamster
hamster-applet: /usr/share/applications/hamster-applet.desktop
hamster-applet: /usr/share/gnome/help/hamster-applet/es/statistics.page
[…]
hamster-applet: /usr/bin/hamster-time-tracker
[…]

Or you can also verify in the list of installed packages:

$ dpkg -l "*hamster*"
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name            Version         Description
+++-===============-===============-==============================================
ii  hamster-applet  2.32.1-1        time tracking applet for GNOME

3. Verify that the bug is not already reported and/or fixed

If there’s a newer version of the software available, it’s a good idea to try to reproduce the problem with this version too. Because the developers tend to care only about the latest version, they will want to reproduce it with this version, and they will be annoyed if the problem that you reported is already fixed. That’s why bug reports of users of testing/unstable tend to be more useful than bug reports of stable users.

In any case, you want to verify that the bug has not yet been reported: filing a duplicate bug is useless and only generates more work for the developers to merge both bugs together. On the opposite, it’s highly appreciated to add supplementary information to an existing bug report, even a simple confirmation that the bug still exists on a newer version is useful.

Note that reportbug will automatically show you the list of open bugs before allowing you to submit a new one.

4. Use reportbug

While the Debian bug tracking system allows anyone to submit a new bug with a simple mail, you should really use a dedicated program like reportbug (or reportbug-ng) because it will automatically include lots of useful information in the generated report (version of dependencies, current architecture, etc.) and will assist you in all the steps.

5. Describe the problem so that the developer can reproduce it

Ideally your report should include everything required so that the developer can reproduce the problem on his system. If a given document triggers the bug, attach it.

Describe the steps required to reproduce the bug in great details just like you would explain it to your grand-ma. Explain how you expected the program to react and what happened instead.

You can learn much more on how to draft a good bug report in this article: How to report bugs effectively. It’s a bit long but well worth it if you intend to report bugs and thus interact with developers.

6. Be kind and willing to help

When you draft a bug report, keep in mind that you’re writing to a volunteer free software developer and not to a customer service. You should be respectful and follow the usual rules of courtesy. Developers’ attention is scarce and should not be wasted.

Be willing to help, if the developer starts investigating your problem, he might need your help to get supplementary information (in particular if he can’t reproduce it) and you should be ready to provide it. Thus it’s important to keep whatever you need to reproduce the problem.

In some cases, the Debian maintainer might be overworked and you can offer your help to forward the bug to the upstream bug tracker, it’s always appreciated. If you’re reasonably confident that the problem is not Debian-specific, you can do it straight away and set the forwarded field to the URL of the upstream bug report (for example with bts forwarded <bug> <url>).

7. Use the correct severity

The Debian bug tracking system lets you set the initial severity of the bug report (in decreasing severity: critical, grave, serious, important, normal, minor, wishlist). Pick the correct severity according to the official definitions but don’t misread them.

In particular, don’t over-inflate the severity: for instance if you lost some data due to a misuse of the software, it’s not “critical” (i.e. “rm -rf *” doesn’t warrant a critical bug against rm). If you use only a tiny part of a software, and that part doesn’t work, the package might be unusable for you but it’s not unusable for everybody, so it doesn’t warrant the “grave” severity. The “important” severity is often a good choice in those cases.

Do not under-estimate the severity either, if a problem is important enough that it must be fixed before the next stable release (for example a regression compared to the previous release), pick a release-critical severity (i.e. at least “serious”). The maintainer and the release manager can always lower the severity if they do not agree with your initial judgment.

And now, happy bug-reporting! You can refer to this article with this shorter URL: http://raphaelhertzog.com/go/bugreporting/

Follow me on Identi.ca, Twitter and Facebook. Or subscribe to this blog by RSS or by email.

How to prepare patches for Debian packages

You want to start contributing to Debian and/or Ubuntu, you decided to help a package maintainer and you’re now looking for how to change a source package and how to submit your changes.

1. Retrieve the source package and install build-dependencies

The first step is to retrieve the latest version of the source package and to install the required build-dependencies. I already covered how to do this with apt-get in the article explaining how to rebuild a source package.

If you prefer, you can use dget (from the devscripts package) to directly grab the source package. You can find the URL of the .dsc files in the Package Tracking System for example.

Sometimes apt-get will warn you that the source package is maintained in a VCS repository, like this:

$ apt-get source wordpress
[...]
NOTICE: 'wordpress' packaging is maintained in the 'Git' version control system at:
git://git.debian.org/git/collab-maint/wordpress.git
[...]

In that case, you can use debcheckout to retrieve the VCS repository instead (provided that you have the corresponding VCS installed):

$ debcheckout wordpress
declared git repository at git://git.debian.org/git/collab-maint/wordpress.git
git clone git://git.debian.org/git/collab-maint/wordpress.git wordpress ...
Cloning into wordpress...

Note however that some maintainers use their VCS in a way that’s not really compatible with the explanations that I will give below.

It’s also a good idea to install the package “packaging-dev”. It’s a meta-package depending on the most common tools that are used for Debian packaging work.

2. Do the changes

Execute dch --nmu to record the fact that you’re working on an update prepared by someone who is not the maintainer (NMU means Non Maintainer Upload). This also ensures that if we build the package, we won’t overwrite the original source package that we downloaded, thus making it possible to generate a “diff” between both versions.

2.1. Modify Debian packaging files

Now fire your text editor and do the required changes in the “debian” sub-directory. You will probably run dch -a multiple times to document each subsequent change.

2.2. Modify upstream files

If you have to modify upstream files, the proper way to do it depends on the source package format (“1.0″ vs “3.0 (quilt)” vs “3.0 (native)”, see the debian/source/format file) and on the presence or not of a patch system (the what-patch can help you identify it). In this explanation, I’ll assume that the package is using the recommended format: “3.0 (quilt)”. (It also works for “1.0″ if quilt is used and if you configured ~/.quiltrc as recommended by /usr/share/doc/quilt/README.source).

First you should ensure that all patches have been applied with quilt push -a. If there’s no patch yet, you want to create the debian/patches directory (with mkdir debian/patches). Note that you should better invoke quilt from the root of the source package (and the examples below assume this).

2.2.1. Import a patch

If the upstream changes are already in a patch file (say /tmp/patch that you downloaded from the upstream VCS repository) you can import that patch like this:

$ quilt import -P fix-foobar.patch /tmp/patch
Importing patch /tmp/patch (stored as fix-foobar.patch)
$ quilt push
Applying patch fix-foobar.patch
[...]
Now at patch fix-foobar.patch

The -P option allows to select the name of the patch file created in debian/patches/. As you see, the new patch file is recorded in debian/patches/series but not applied by default, we’re thus doing it with quilt push.

2.2.1. Create a new patch

If the upstream changes that you want to make are not in a patch yet, you should tell quilt that you’re going to create one:

$ quilt new fix-foobar.patch
Patch fix-foobar.patch is now on top

Then you must record every file that you’re going to modify with a quilt add invocation. quilt then makes a backup of those files so that it can generate the patch later on. If you’re going to modify the files with your text editor you can just do quilt edit file-to-modify, it’s the same than quilt add file-to-modify followed by sensible-editor file-to-modify.

$ quilt edit foobar.c
File foobar.c added to patch fix-foobar.patch

The last step is tell quilt to generate the patch:

$ quilt refresh
Refreshed patch fix-foobar.patch

3. Test your changes

You should build your modified package with “debuild -us -uc”. You can easily install the resulting package with “debi”. Verify that everything works as expected. If not, continue your modifications until you’re satisfied with the result.

4. Generate a patch and mail it

If you followed the instructions, you should have two .dsc files in the parent directory, like this:

$ cd ..
$ ls wordpress_*.dsc
../wordpress_3.0.5+dfsg-1.1.dsc
../wordpress_3.0.5+dfsg-1.dsc

Generating the patch to send to the maintainer is then just a matter of running debdiff:

$ debdiff wordpress_3.0.5+dfsg-1.dsc wordpress_3.0.5+dfsg-1.1.dsc >/tmp/wp-debdiff

You can send the /tmp/wp-debdiff file to the wordpress maintainer. Usually you send it via the bugreport that your update is fixing and you add the “patch” tag to the report.

This can be automated with the nmudiff utility. By default it assumes that you’re using mutt but it can also directly feed the resulting mail to sendmail. The default text that nmudiff proposes assumes that you’re actually performing an NMU and that the result has been uploaded. If that’s not the case, you should edit the text and make it clear that you’re just sending a patch.

If you have been working in a VCS repository, instead of using debdiff you can simply use the diff feature integrated in your VCS (git diff, svn diff, etc.). But note that with a distributed VCS (like git/bzr/mercurial, unlike svn) you should probably have committed all individual changes in separate changesets. And instead of sending a single patch, you’re probably going to send a series of patches (though it might be easier to just upload your branch in a public repository and give the corresponding URL to the maintainer).

Found it useful? Be sure to not miss other packaging tips (or lessons), click here to subscribe to my free newsletter and get new articles by email.

My Debian activities in June 2011

This is my monthly summary of my Debian related activities. If you’re among the people who made a donation to support my work (195 €, thanks everybody!), then you can learn how I spent your money. Otherwise it’s just an interesting status update on my various projects.

Dropbox for Debian

This is not free software but Dropbox is very popular and they did only provide an Ubuntu package that did not work on Debian. So I created an official package.

I have been in touch with Dropbox developers and they have been very helpful. They’ll shortly release a signature mechanism (with GPG) so that we can further improve the package by verifying the origin of the downloaded binaries.

SAT Britney

At the start of the month, I continued my work on the britney reimplementation (the software that creates testing out of unstable) but I quickly stalled it because the release managers asked the feedback of Stefano Zacchiroli and Ralf Treinen (who have extensive knowledge on the topic with their research work on Mancoosi) and I did not want to invest further work in case they would identify a major flow… the feedback came only very late this month and while it was somewhat negative, I still think it’s worth pursuing the effort for a bit longer.

Converted ftplib to multiarch

While dpkg still doesn’t support multiarch (no news from Guillem and no visible sign of progress :-(), unstable got all the remaining bits allowing us to convert libraries to multiarch (see the announce). As soon as the required libc6 landed in unstable, I looked into converting the only library package that I maintain. I had no major problem but I still identified 2 issues in Lintian (filed as #630164 and quickly fixed by Niels Thykier).

build-arch / build-indep support

For the 42th time in the last 10 years, the idea of using build-arch/build-indep targets in the rules file has surfaced again. I had already decided some time ago that I would accept a patch implementing a new field Build-Features to enable dpkg-buildpackage to use those targets and this time Bill Allombert completed such a patch so I merged it.

The technical committee also decided that it would take a final decision on this topic (see #629385). Roger Leigh provided useful input by doing an archive-wide rebuild with the various solutions suggested. Given that the majority would like to make the target mandatory at some point in the future, I provided the dpkg patch for my preferred solution. We would use “auto-detection” as a temporary measure until all packages have been converted to have the targets.

The technical committee has not yet taken any decision even though the discussion stalled since the 12th of June. But that’s usual with that body. I’m sure it will be solved during Debconf. ;-)

Misc dpkg work

  • Modified dpkg-source --after-build to automatically unapply patches if they have been applied by dpkg-source --before-build.
  • Lots of small bug fixes (#628726, #629582, #630996, #631435, #631439, #631547, #632168) and that’s just to keep with the flow of incoming bug reports!
  • Added 2 supplementary Perl modules to the supported API for the benefit of Lintian.
  • Spent an evening to track down the possible causes of an long-standing and annoying assertion failure related to triggers.
  • Updated my branch with improved triggers directives to take into account the feedback of Guillem, and merged it.
  • While doing this I discovered a design flaw with the usage of “prerm failed-upgrade” and merged a fix.
  • Discussed integration of dpkg-buildflags with debhelper in #544844 and decided of further improvements for dpkg-buildflags as a result.

Hamster applet update

Hamster-applet is a GNOME application which did not have a 3.0 release, but it had a development release (2.91.x). I checked out whether it was possible to package this version for experimental and have the applet work with the GNOME fallback mode. Apparently not, the code was not yet updated to be compatible with the newer panel.

Instead I uploaded the latest stable version (2.32.1) to unstable. It has some nice improvements in the standalone version (and the name of the executable changed). For usage with GNOME 3, I have created a custom shortcut to start it quickly (with gconf-editor set /apps/metacity/global_keybindings/run_command_1 to “<Mod4>t” and /apps/metacity/keybinding_commands/command_1 to “hamster-time-tracker” because the GNOME 3 control panel does not seem to work to set custom keybindings currently).

Translated my professional website into English

While I’m grateful for all the people who are supporting my work, I’m still far from my goal to have one third of my time funded through donations and sales of products on this blog.

So I decided to also bring more visibility to my company and in particular to its Debian-related service offering. It was only available in French up to now so I translated it and expanded it a bit. My “support page” on this blog now also links to my company’s website.

If your company needs help to create Debian packages, or needs Debian technical support by email, you just found the right partner. :-)

BTW, I have discounted prices for individuals and non-profits who would like to benefit from my help to create Debian packages.

The Debian Administrator’s Handbook

This is the title of the upcoming translation of my book. The project now has a dedicated website: debian-handbook.info.

You can subscribe to its RSS feed to keep up with the latest news. The full table of contents is online along with a FAQ.

I’m actively looking for partners to help me promote the fundraising once it goes live. If you can reach a large set of readers interested by a good Debian book, get in touch with me to join the affiliate program.

Thanks

See you next month for a new summary of my activities.

Discover 5 free software that you can support with Flattr

Flattr FOSS Logo

  1. The Board (Flattr link) is a sort of digital scrapbook. You can quickly paste and mix notes, pictures, videos, audio recording, … all on virtual pages. The result is very nice and it’s a GNOME application.
  2. Knights (Flattr link) is a chess game for KDE. It’s nice to see some KDE applications on Flattr!
  3. Syncany (Flattr link) is dropbox-like service (file synchronization between multiple computers) except that you can choose where to host your data. It’s a recent project but it looks very promising!
  4. JDownloader (Flattr link) is a java application that simpliefies download of files from One-Click-Hosters like Rapidshare.com or Megaupload.com. It offers downloading in multiple parallel streams, captcha recognition, automated file extraction, and much more.
  5. Ball and Paddle (Flattr link) is an extensible ball and paddle game that lets you script the events and attributes of the objects (balls, blocks, powerups, etc.) with GNU Guile, the official GNU extension language. It’s a GNU project: Flattr seems to be popular among GNU authors apparently. :)

This article is part of the Flattr FOSS project.