Desktop environment
A desktop environment (DE) is an implementation of the desktop metaphor made of a bundle of programs, which share a common graphical user interface (GUI).
Contents
Overview
A desktop environment bundles together a variety of components to provide common graphical user interface elements such as icons, toolbars, wallpapers, and desktop widgets. Additionally, most desktop environments include a set of integrated applications and utilities. Most importantly, desktop environments provide their own window manager, which can however usually be replaced with another compatible one.
The user is free to configure their GUI environment in any number of ways. Desktop environments simply provide a complete and convenient means of accomplishing this task. Note that users are free to mix-and-match applications from multiple desktop environments. For example, a KDE user may install and run GNOME applications such as the Epiphany web browser, should they prefer it over KDE’s Konqueror web browser. One drawback of this approach is that many applications provided by desktop environment projects rely heavily upon the libraries underlying the respective desktop environment. As a result, installing applications from a range of desktop environments will require installation of a larger number of dependencies. Users seeking to conserve disk space often avoid such mixed environments, or chose alternatives which do depend on only few external libraries.
Furthermore, applications provided by desktop environments tend to integrate better with their native environments. Superficially, mixing environments with different widget toolkits will result in visual discrepancies (that is, interfaces will use different icons and widget styles). In terms of usability, mixed environments may not behave similarly (e.g. single-clicking versus double-clicking icons; drag-and-drop functionality) potentially causing confusion or unexpected behavior.
List of desktop environments
Officially supported
- Budgie — Budgie is a desktop environment designed with the modern user in mind, it focuses on simplicity and elegance.
https://getsol.us/ || budgie-desktop
- Cinnamon — Cinnamon strives to provide a traditional user experience. Cinnamon is a fork of GNOME 3.
https://github.com/linuxmint/Cinnamon || cinnamon
- Cutefish — Cutefish is a new and modern desktop environment.
https://en.cutefishos.com/ || cutefish
- Deepin — Deepin desktop interface and apps feature an intuitive and elegant design. Moving around, sharing and searching etc. has become simply a joyful experience.
https://www.deepin.org/ || deepin
- Enlightenment — The Enlightenment desktop shell provides an efficient window manager based on the Enlightenment Foundation Libraries along with other essential desktop components like a file manager, desktop icons and widgets. It supports themes, while still being capable of performing on older hardware or embedded devices.
https://www.enlightenment.org/ || enlightenment
- GNOME — The GNOME desktop environment is an attractive and intuitive desktop with both a modern (GNOME) and a classic (GNOME Classic) session.
https://www.gnome.org/ || gnome
- GNOME Flashback — GNOME Flashback is a shell for GNOME 3 which was initially called GNOME fallback mode. The desktop layout and the underlying technology is similar to GNOME 2.
https://wiki.gnome.org/Projects/GnomeFlashback || gnome-flashback
- KDE Plasma — The KDE Plasma desktop environment is a familiar working environment. Plasma offers all the tools required for a modern desktop computing experience so you can be productive right from the start.
https://www.kde.org/plasma-desktop || plasma
- LXDE — The Lightweight X11 Desktop Environment is a fast and energy-saving desktop environment. It comes with a modern interface, multi-language support, standard keyboard short cuts and additional features like tabbed file browsing. Fundamentally designed to be lightweight, LXDE strives to be less CPU and RAM intensive than other environments.
https://lxde.org/ || GTK 2: lxde , GTK 3: lxde-gtk3
- LXQt — LXQt is the Qt port and the upcoming version of LXDE, the Lightweight Desktop Environment. It is the product of the merge between the LXDE-Qt and the Razor-qt projects: A lightweight, modular, blazing-fast and user-friendly desktop environment.
https://lxqt.github.io/ || lxqt
- MATE — Mate provides an intuitive and attractive desktop to Linux users using traditional metaphors. MATE started as a fork of GNOME 2, but now uses GTK 3.
https://mate-desktop.org/ || mate
- Sugar — The Sugar Learning Platform is a computer environment composed of Activities designed to help children from 5 to 12 years of age learn together through rich-media expression. Sugar is the core component of a worldwide effort to provide every child with the opportunity for a quality education — it is currently used by nearly one-million children worldwide speaking 25 languages in over 40 countries. Sugar provides the means to help people lead fulfilling lives through access to a quality education that is currently missed by so many.
https://sugarlabs.org/ || sugar + sugar-fructose
- UKUI — UKUI is a lightweight Linux desktop environment, developed based on GTK and Qt. UKUI is the default desktop environment for Ubuntu kylin.
https://www.ukui.org/ || ukui
- Xfce — Xfce embodies the traditional UNIX philosophy of modularity and re-usability. It consists of a number of components that provide the full functionality one can expect of a modern desktop environment, while remaining relatively light. They are packaged separately and you can pick among the available packages to create the optimal personal working environment.
https://xfce.org/ || xfce4
Unofficially supported
- CDE — The Common Desktop Environment is a desktop environment for Unix and OpenVMS, based on the Motif widget toolkit. It was part of the UNIX98 Workstation Product Standard, and was long the «classic» Unix desktop associated with commercial Unix workstations. Despite being a legacy environment, it is still kept alive with support for Linux systems as well.
https://sourceforge.net/projects/cdesktopenv/ || cdesktopenvAUR
- EDE — The «Equinox Desktop Environment» is a desktop environment designed to be simple, extremely light-weight and fast.
https://edeproject.org/ || edeAUR
- KDE 1 — «forward-ported» to work on modern systems. Mostly for nostalgia, but now actually works and can be used as a daily driver. There are also a growing number of KDE 1 applications in AUR.
https://invent.kde.org/historical/kde1-kdebase || kde1-kdebase-gitAUR
- Liri — Liri is a desktop environment with modern design and features. Liri is the merge between Hawaii, Papyros and the Liri Project. Highly experimental.
https://liri.io/ || liri-shell-gitAUR
- Lumina — Lumina is a lightweight desktop environment written in Qt 5 for FreeBSD that uses Fluxbox for window management.
https://lumina-desktop.org/ || lumina-desktopAUR
- Moksha — Fork of Enlightenment currently used as default desktop environment in Ubuntu-based Bodhi Linux.
https://www.bodhilinux.com/moksha-desktop/ || moksha-gitAUR
- Pantheon — Pantheon is the default desktop environment originally created for the elementary OS distribution. It is written from scratch using Vala and the GTK3 toolkit. With regards to usability and appearance, the desktop has some similarities with GNOME Shell and macOS.
https://elementary.io/ || pantheon-session-gitAUR
- PaperDE — Desktop environment built on top of Qt/Wayland and wayfire.
https://cubocore.org/paperde.html || paperdeAUR
- Phosh — Phosh is a Wayland shell user interface based on GNOME, useful on mobile devices.
https://gitlab.gnome.org/World/Phosh/phosh || phoshAUR , phosh-gitAUR
- theDesk — theDesk is a desktop environment that tries to be as transparent as possible. It uses Qt 5 as its widget toolkit and KWin as its window manager.
https://github.com/vicr123/thedesk || thedeskAUR
- Trinity — The Trinity Desktop Environment (TDE) project is a computer desktop environment for Unix-like operating systems with a primary goal of retaining the overall KDE 3.5 computing style.
https://www.trinitydesktop.org/ || See Trinity
Custom environments
Desktop environments represent the simplest means of installing a complete graphical environment. However, users are free to build and customize their graphical environment in any number of ways if none of the popular desktop environments meet their requirements. Generally, building a custom environment involves selection of a suitable window manager or compositor, a taskbar and a number of applications (a minimalist selection usually includes a terminal emulator, file manager, and text editor).
Other components usually provided by desktop environments are:
Use a different window manager
If the desktop environment has an article, see its Use a different window manager section, otherwise consult the official documentation.
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Environment variables
An environment variable is a named object that contains data used by one or more applications. In simple terms, it is a variable with a name and a value. The value of an environmental variable can for example be the location of all executable files in the file system, the default editor that should be used, or the system locale settings. Users new to Linux may often find this way of managing settings a bit unmanageable. However, environment variables provide a simple way to share configuration settings between multiple applications and processes in Linux.
Contents
Utilities
The coreutils package contains the programs printenv and env. To list the current environmental variables with values:
The env utility can be used to run a command under a modified environment. The following example will launch xterm with the environment variable EDITOR set to vim . This will not affect the global environment variable EDITOR .
The Bash builtin set allows you to change the values of shell options and set the positional parameters, or to display the names and values of shell variables. For more information, see the set builtin documentation.
Each process stores their environment in the /proc/$PID/environ file. This file contains each key value pair delimited by a nul character ( \x0 ). A more human readable format can be obtained with sed, e.g. sed ‘s:\x0:\n:g’ /proc/$PID/environ .
Defining variables
Globally
Most Linux distributions tell you to change or add environment variable definitions in /etc/profile or other locations. Keep in mind that there are also package-specific configuration files containing variable settings such as /etc/locale.conf . Be sure to maintain and manage the environment variables and pay attention to the numerous files that can contain environment variables. In principle, any shell script can be used for initializing environmental variables, but following traditional UNIX conventions, these statements should only be present in some particular files.
The following files should be used for defining global environment variables on your system: /etc/environment , /etc/profile and shell specific configuration files. Each of these files has different limitations, so you should carefully select the appropriate one for your purposes.
- /etc/environment is used by the pam_env module and is shell agnostic so scripting or glob expansion cannot be used. The file only accepts variable=value pairs. See pam_env(8) and pam_env.conf(5) for details.
- /etc/profile initializes variables for login shells only. It does, however, run scripts and can be used by all Bourne shell compatible shells.
- Shell specific configuration files — Global configuration files of your shell, initializes variables and runs scripts. For example Bash#Configuration files or Zsh#Startup/Shutdown files.
In this example, we add
/bin directory to the PATH for respective user. To do this, just put this in your preferred global environment variable config file ( /etc/profile or /etc/bash.bashrc ):
Per user
You do not always want to define an environment variable globally. For instance, you might want to add /home/my_user/bin to the PATH variable but do not want all other users on your system to have that in their PATH too. Local environment variables can be defined in many different files:
/.pam_environment is the user specific equivalent of /etc/security/pam_env.conf [1], used by pam_env module. See pam_env(8) and pam_env.conf(5) for details.
To add a directory to the PATH for local usage, put following in
To update the variable, re-login or source the file: $ source
/.bashrc etc. This means that, for example, dbus activated programs like Gnome Files will not use them by default. See Systemd/User#Environment variables.
Reading
/.pam_environment is deprecated and the feature will be removed at some point in the future.
Graphical environment
Environment variables for Xorg applications can be set in xinitrc, or in xprofile when using a display manager, for example:
The factual accuracy of this article or section is disputed.
/.config/environment.d/ on Wayland sessions is GDM-specific behavior. (Discuss in Talk:Environment variables)
Applications running on Wayland may use systemd user environment variables instead, as Wayland does not initiate any Xorg related files:
To set environment variables only for a specific application instead of the whole session, edit the application’s .desktop file. See Desktop entries#Modify environment variables for instructions.
Per session
Sometimes even stricter definitions are required. One might want to temporarily run executables from a specific directory created without having to type the absolute path to each one, or editing shell configuration files for the short time needed to run them.
In this case, you can define the PATH variable in your current session, combined with the export command. As long as you do not log out, the PATH variable will be using the temporary settings. To add a session-specific directory to PATH , issue:
Examples
The following section lists a number of common environment variables used by a Linux system and describes their values.
- DE indicates the Desktop Environment being used. xdg-open will use it to choose more user-friendly file-opener application that desktop environment provides. Some packages need to be installed to use this feature. For GNOME, that would be libgnomeAUR ; for Xfce this is exo . Recognised values of DE variable are: gnome , kde , xfce , lxde and mate .
The DE environment variable needs to be exported before starting the window manager. For example: This will make xdg-open use the more user-friendly exo-open, because it assumes it is running inside Xfce. Use exo-preferred-applications for configuring.
- DESKTOP_SESSION is similar to DE , but used in LXDE desktop environment: when DESKTOP_SESSION is set to LXDE , xdg-open will use PCManFM file associations.
- PATH contains a colon-separated list of directories in which your system looks for executable files. When a regular command (e.g. ls, systemctl or pacman) is interpreted by the shell (e.g. bash or zsh), the shell looks for an executable file with the same name as your command in the listed directories, and executes it. To run executables that are not listed in PATH , a relative or absolute path to the executable must be given, e.g. ./a.out or /bin/ls .
- HOME contains the path to the home directory of the current user. This variable can be used by applications to associate configuration files and such like with the user running it.
- PWD contains the path to your working directory.
- OLDPWD contains the path to your previous working directory, that is, the value of PWD before last cd was executed.
- TERM contains the type of the running terminal, e.g. xterm-256color . It is used by programs running in the terminal that wish to use terminal-specific capabilities.
- MAIL contains the location of incoming email. The traditional setting is /var/spool/mail/$LOGNAME .
- ftp_proxy and http_proxy contains FTP and HTTP proxy server, respectively:
- MANPATH contains a colon-separated list of directories in which man searches for the man pages.
- INFODIR contains a colon-separated list of directories in which the info command searches for the info pages, e.g., /usr/share/info:/usr/local/share/info
- TZ can be used to to set a time zone different to the system zone for a user. The zones listed in /usr/share/zoneinfo/ can be used as reference, for example TZ=»:/usr/share/zoneinfo/Pacific/Fiji» . When pointing the TZ variable to a zoneinfo file, it should start with a colon per the GNU manual.
Default programs
- SHELL contains the path to the user’s preferred shell. Note that this is not necessarily the shell that is currently running, although Bash sets this variable on startup.
- PAGER contains command to run the program used to list the contents of files, e.g., /bin/less .
- EDITOR contains the command to run the lightweight program used for editing files, e.g., /usr/bin/nano . For example, you can write an interactive switch between gedit under X or nano, in this example:
- VISUAL contains command to run the full-fledged editor that is used for more demanding tasks, such as editing mail (e.g., vi , vim, emacs etc).
- BROWSER contains the path to the web browser. Helpful to set in an interactive shell configuration file so that it may be dynamically altered depending on the availability of a graphic environment, such as X:
Using pam_env
The PAM module pam_env(8) loads the variables to be set in the environment from the following files: /etc/security/pam_env.conf , /etc/environment and
- /etc/environment must consist of simple VARIABLE=value pairs on separate lines, for example:
- /etc/security/pam_env.conf and
/.pam_environment share the same following format: @
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