Advanced KDE Administration

For general use, it is sufficient to configure KDE using the options provided in System Settings and in individual application settings. Nevertheless, to unlock the full power of KDE, you should learn some of the system administration tools that it provides.

Every KDE applications has its own unique command line options. Additionally, each application has access to general KDE options and general Qt options. To see only the application options, open a terminal window (such as Konsole), and type the application name followed by “--help

For example,

kate --help

To see all options, add “-all”

kate --help-all

You can also use “--help-qt” and “--help-kde“.

An example of a powerful KDE option is “--config“, which gives you the ability to use an alternate configuration file, different that the standard one used by the application. With this option, you can run two separate variations of the same application.

With the Qt options, you can access advanced features like “--display“, which allows you to specify which X server display you want your application to appear on, something useful when working with multiple instances of X.

Other KDE options include titlebar caption, application icon, disabling the crash handler, GUI style, and geometry. Other Qt options include session ID, disabling mouse/keyboard grab, font, background color, application name/title, input style, and more.

KDE configuration and application files are kept in the home folder under ~/.kde. This is a hidden directory that you can access by clicking at the end of the Dolphin breadcrumbs to “edit location” and then typing it into the box. You can also hold the Alt key and press the period key (Alt + .) to show hidden files. Some of the folders like cache, socket, and tmp are ones you will rarely, if ever, need to access. Others, like share, are very useful for advanced configuration.

KDEHOME folder

Accessing the share folder

The share folder holds a number of important subfolders, including config, apps, icons, and wallpapers.

1. The config folder holds the user’s configuration files for KDE applications. These files are specific to the user, and changes to them will only change the KDE settings for that user. The main KDE config file is kdeglobals. All of the configuration files are text-based and easily editable in a normal text editor like KWrite. Generally, you do not need to manipulate these files directly, but there are cases when you might tap into undocumented features.

KDE Config folder

Configuration files are formatted with group names, enclosed in brackets [GroupName] and keys listed under them.

For example, this is one config group from the amarokrc file:

[Playlist Search]
MatchAlbum=true
MatchArtist=true
MatchTrack=true

Editing configuration files is one way to configure KDE and then distribute those configuration changes over multiple systems via a network.

In addition to the local user configuration files, those changes to files in /etc/skel will affect any new users that you create, making it easy to have a custom installation of KDE that defaults to the settings you configured for each new user.

kdeglobals config file in KWrite

2. The apps folder holds folders containing user files for every KDE application. For example, the akregator folder will hold the local user’s feeds.opml file. Similarly, the kmail folder holds the user’s mailboxes.

3. The icons folder holds user-installed icons. You can download icon sets from KDE-Look.org and extract their subfolder directly into this folder. You can also create your own icons and place them here.

4. Similar to icons, user wallpapers are stored in the wallpapers folder. This is only where the KDE wallpaper installation component places them, so you do not need to put wallpapers here in order to use them.

Both the icons and wallpapers folders are for the local user and will not affect other users globally.

KDE has a plethora of Unix/Linux environment variables that you can use to control how KDE starts up and runs. For example, KDEHOME determines where the default KDE files are held (~/.kde is the default). KDETEMP determines what temporary directory it uses. There are also number debugging environment variables for troubleshooting.

Including all of the documentation on KDE administration and configuration would make this article unduly long, but there are plenty of resources to help you along the way. The most important resources are KDE UserBase and KDE TechBase. In particular, you should read the System Administration section of KDE TechBase.