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Deb-triggers and Plymouth - notes

Today just a short post, glued together from a few small things that I found useful - more specifically, regarding deb-triggers and some old Plymouth bits. Anyway, geh, it's so busy lately...

2012-03-16 09:38

First of all, some loose things about Debian packages. Lately I had really much contact with package creation and management. Debian packages are a powerful tool - actually, even basing a build system for cross-compiled embedded systems on .deb wouldn't be such a bad idea.
Recently I learned about the existence of deb-triggers - a very useful mechanism for registering common actions that should be performed by all installed packages as result of a specified action. For example, a package can register a trigger to be run when any Debian package installs/copies a file to a given directory. This can be useful when, for instance, we want to update some cache file whenever new entries are installed by a different package. Examples: texinfo documentation, gtk2/3 IM cache entries.

When a trigger is 'triggered', the postinst script of the trigger-registering package is called with some additional arguments. Besides triggering on directory modification, triggers can also be fired directly by packaged using dpkg-trigger. Very useful thing. You can read more about it on man deb-triggers, man dpkg-trigger and on this nicely written howto.

Now a small thing about Plymouth. Here's a useful batch of Plymouth commands that can be used in your system init shell script (in the initramfs). It's nothing new, but useful to have a list of:

That's all for today. In the nearest future I'm planning on writing a bit about Maliit plugin development and Compiz plugin development. I just need to find a bit more free time, since I actually picked up too much things lately. Stay tuned!
And by the way - new Unity (5.6.0) has been released! Testing is welcome!