Display manager linux debian
Simple Desktop Display Manager (SDDM) is a cross-desktop X11 and Wayland display manager. It was built to be modern, fast, simple, beautiful, and highly customizable. It is based on Qt and its markup language QML and has customizable looks using themes. It is the standard display manager of the Qt-based desktop environments KDE and LXQt. It is present in Debian stable since stretch (Debian 9).
To install SDDM, run as root or prepended by sudo:
or search SDDM in your favorite graphical APT frontend like e.g. Synaptic and install it from there.
System-wide configuration
In the simplest case, configuration is in /etc/sddm.conf.
Configuration files can also be in /usr/lib/sddm/sddm.conf.d/ or in /etc/sddm.conf.d/.
The man page for sddm.conf contains a comprehensive list of options.
To change the current default Display Manager, run
Enable autologin
Put this stanza in /etc/sddm.conf or in /etc/sddm.conf.d/autologin or in another configuration file in /etc/sddm.conf.d/.
[Autologin] User=USERNAME Session=DENAME.desktop Relogin=false
USERNAME must be replaced with the name of the user to be logged in.
DENAME must be replaced with the name of one of the files found under /usr/share/xsessions/ or /usr/share/wayland-sessions/. E.g. plasma for KDE or lxqt for LXQt.
When Relogin is false or left blank, SDDM will autologin only for first login after boot. If set true autologin will be repeated immediately after logout.
See also
Display manager linux debian
The graphical interface only provides display space. Running the X server by itself only leads to an empty screen, which is why most installations use a display manager to display a user authentication screen and start the graphical desktop once the user has authenticated. The three most popular display managers in current use are gdm3 ( GNOME Display Manager ), sddm (suggested for KDE Plasma) and lightdm ( Light Display Manager ). More alternatives exist and can be found by searching for the x-display-manager virtual package.
Since the Falcot Corp administrators have opted to use the GNOME desktop environment, they logically picked gdm3 as a display manager too. The /etc/gdm3/daemon.conf configuration file has many options (the list can be found in the /usr/share/gdm/gdm.schemas schema file) to control its behavior while /etc/gdm3/greeter.dconf-defaults contains settings for the greeter “session” (more than just a login window, it is a limited desktop with power management and accessibility related tools). Note that some of the most useful settings for end-users can be tweaked with GNOME’s control center.
13.2.2. Выбор оконного менеджера
Since each graphical desktop provides its own window manager, which window manager you choose is usually influenced by which desktop you have selected. GNOME uses the mutter window manager, Plasma uses kwin , and Xfce (which we present later) has xfwm . The Unix philosophy always allows using one’s window manager of choice, but following the recommendations allows an administrator to best take advantage of the integration efforts led by each project.
НАЗАД К ОСНОВАМ Оконный менеджер
The window manager displays the “decorations” around the windows belonging to the currently running applications, which includes frames and the title bar. It also allows reducing, restoring, maximizing, and hiding windows. Most window managers also provide a menu that pops up when the desktop is clicked in a specific way. This menu provides the means to close the window manager session, start new applications, and in some cases, change to another window manager (if installed).
Older computers may, however, have a hard time running heavyweight graphical desktop environments. In these cases, a lighter alternative (search for the x-window-manager virtual package) should be used. “Light” (or small footprint) window managers include WindowMaker (in the wmaker package), afterstep , icewm , blackbox , fluxbox , or openbox . In these cases, the system should be configured so that the appropriate window manager gets precedence; the standard way is to change the x-window-manager alternative with the command update-alternatives —config x-window-manager .
ОСОБЕННОСТИ DEBIAN Альтернативы
Политика Debian перечисляет ряд стандартизированных команд, предназначенных для выполнения определенных действий. Например, команда x-window-manager вызовет менеджер окон. Но Debian не жёстко ассоциирует эту команду с каким-то одним оконным менеджером. Администратор может выбрать, какой оконный менеджер должна вызывать эта команда.
Для каждого оконного менеджера соответствующий пакет регистрирует свою команду запуска со своим приоритетом как возможный выбор для x-window-manager . В случае отсутствия явной настройки администратором, установленный приоритет позволяет выбрать для запуска лучший установленный менеджер окон.
Both the registration of commands and the explicit configuration involve the update-alternatives script. Choosing where a symbolic command points at is a simple matter of running update-alternatives —config symbolic-command . This script creates (and maintains) symbolic links in the /etc/alternatives/ directory, which in turn references the location of the executable. As time passes, packages are installed or removed, and/or the 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.
Не все символические команды явно перечислены в политике Debian. Некоторые сопровождающие пакетов Debian намеренно используют этот механизм в менее простых случаях, когда он все еще приносит гибкость (например x-www-browser , www-browser , cc , c++ , awk и т.д.).
13.2.3. Управление меню
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, each package usually provides a .desktop file in /usr/share/applications . The format of those files has been standardized by FreeDesktop.org:
The applications menus can be further customized by administrators through system-wide configuration files as described by the “Desktop Menu Specification”. End-users can also customize the menus with graphical tools such as kmenuedit (in Plasma), alacarte (in GNOME) or menulibre .
ИСТОРИЯ Система меню Debian
Исторически, прежде чем появились стандарты FreeDesktop.org, в Debian использовалась своя собственная система меню, где каждый пакет, предоставлял описание желаемых пунктов меню в /usr/share/menu/ . Этот инструмент еще доступен в Debian (в пакете menu ), но он мало полезен, поскольку сопровождающим пакетов рекомендуется вместо него полагаться на .desktop файлы.
Display manager linux debian
The graphical interface only provides display space. Running the X server by itself only leads to an empty screen, which is why most installations use a display manager to display a user authentication screen and start the graphical desktop once the user has authenticated. The three most popular display managers in current use are gdm3 ( GNOME Display Manager ), sddm (suggested for KDE Plasma) and lightdm ( Light Display Manager ). More alternatives exist and can be found by searching for the x-display-manager virtual package.
Since the Falcot Corp administrators have opted to use the GNOME desktop environment, they logically picked gdm3 as a display manager too. The /etc/gdm3/daemon.conf configuration file has many options (the list can be found in the /usr/share/gdm/gdm.schemas schema file) to control its behavior while /etc/gdm3/greeter.dconf-defaults contains settings for the greeter “session” (more than just a login window, it is a limited desktop with power management and accessibility related tools). Note that some of the most useful settings for end-users can be tweaked with GNOME’s control center.
13.2.2. Choosing a Window Manager
Since each graphical desktop provides its own window manager, which window manager you choose is usually influenced by which desktop you have selected. GNOME uses the mutter window manager, Plasma uses kwin , and Xfce (which we present later) has xfwm . The Unix philosophy always allows using one’s window manager of choice, but following the recommendations allows an administrator to best take advantage of the integration efforts led by each project.
BACK TO BASICS Window manager
The window manager displays the “decorations” around the windows belonging to the currently running applications, which includes frames and the title bar. It also allows reducing, restoring, maximizing, and hiding windows. Most window managers also provide a menu that pops up when the desktop is clicked in a specific way. This menu provides the means to close the window manager session, start new applications, and in some cases, change to another window manager (if installed).
Older computers may, however, have a hard time running heavyweight graphical desktop environments. In these cases, a lighter alternative (search for the x-window-manager virtual package) should be used. “Light” (or small footprint) window managers include WindowMaker (in the wmaker package), afterstep , icewm , blackbox , fluxbox , or openbox . In these cases, the system should be configured so that the appropriate window manager gets precedence; the standard way is to change the x-window-manager alternative with the command update-alternatives —config x-window-manager .
DEBIAN SPECIFICITY Alternatives
The Debian policy lists a number of standardized commands able to perform a particular action. For example, the x-window-manager command invokes a window manager. But Debian does not assign this command to a fixed window manager. The administrator can choose which manager it should invoke.
For each window manager, the relevant package therefore registers the appropriate command as a possible choice for x-window-manager along with an associated priority. Barring explicit configuration by the administrator, this priority allows picking the best installed window manager when the generic command is run.
Both the registration of commands and the explicit configuration involve the update-alternatives script. Choosing where a symbolic command points at is a simple matter of running update-alternatives —config symbolic-command . This script creates (and maintains) symbolic links in the /etc/alternatives/ directory, which in turn references the location of the executable. As time passes, packages are installed or removed, and/or the 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, each package usually provides a .desktop file in /usr/share/applications . The format of those files has been standardized by FreeDesktop.org:
The applications menus can be further customized by administrators through system-wide configuration files as described by the “Desktop Menu Specification”. End-users can also customize the menus with graphical tools such as kmenuedit (in Plasma), alacarte (in GNOME) or menulibre .
HISTORY The Debian menu system
Historically — way before the FreeDesktop.org standards emerged — Debian had invented its own menu system where each package provided a generic description of the desired menu entries in /usr/share/menu/ . This tool is still available in Debian (in the menu package) but it is only marginally useful since package maintainers are encouraged to rely on .desktop files instead.