2 - Raspberry PI Community Projects

administrator makes explicit changes to the configuration. When a package
providing an alternative is removed, the alternative automatically goes to the
next best choice among the remaining possible commands.
Not all symbolic commands are explicitly listed by the Debian policy; some
Debian package maintainers deliberately chose to use this mechanism in less
straightforward cases where it still brings interesting flexibility (examples include
x-www-browser, www-browser, cc, c++, awk, and so on).
13.2.3. Menu Management
Modern desktop environments and many window managers provide menus listing the available
applications for the user. In order to keep menus up-to-date in relation to the actual set
of available applications, Debian created a centralized database registering all installed applications.
A newly installed package registers itself in that database, and tells the system to update
the menus accordingly. This infrastructure is handled in the menu package.
When a package provides an application that should appear in the menu system, it stores a
file in the /usr/share/menu/ directory. That file describes some of the application features
(including whether it's a graphical application or not), and the best location for it in the menu
hierarchy. The post-installation script for this package then runs the update-menus command,
which in turn updates all the required files. This command cannot know all the menu types
used by installed applications. As a consequence, packages able to display a menu must provide
an executable script that will be invoked with all the required information from the menu file;
the script should then turn this information into elements that the application with the menu
can use. These filter scripts are installed in the /etc/menu-methods/ directory.
GOING FURTHER
Menus standardization
Debian provides its own menu system, but both GNOME and KDE developed
their own menu management solutions as well. The two projects agreed on a
format for these menus — more precisely, a common format for the .desktop
files that represent menu elements — under the FreeDesktop.org umbrella
project.
➨ http://www.freedesktop.org/
The Debian developers have kept a close eye on this project and .desktop files
can be generated from the Debian menu system. However, neither GNOME
nor KDE use the Debian menu. They both prefer keeping complete control
over their menus. Still, it is possible to enable a “Debian” submenu containing
the official menu as maintained by Debian: in GNOME, the menu editor (in
the alacarte package) is available by right-clicking on the panel menu, then
choosing “Edit menus”.
The administrator can also have a say in the process and in the resulting generated menus.
First, they can delete a menu element even when the matching application is installed, by simply
storing in /etc/menu/ an empty file named according to the package providing the entries
to be disabled. Second, the menu can be reorganized and sections renamed or grouped.
The /etc/menu-methods/translate_menus file is where this reorganization is defined and
Chapter 13 — Workstation
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