GDM Commands

The gdmXnestchooser command automatically gets the correct display number, sets up access, and runs the nested X server command with the "-indirect localhost" argument. This provides an XDMCP chooser program. You can also supply as an argument the hostname whose chooser should be displayed, so gdmXnestchooser somehost will run the XDMCP chooser from host somehost inside a nested X server session. You can make this command do a direct query instead by passing the -d option as well. In addition to the following options, this command also supports standard GNOME options.

The gdmflexiserver command provides three features. It can be used to run flexible (on demand) X displays, to run a flexible display via nested X server, and to send commands to the GDM daemon process.

Starting a flexible X display will normally lock the current session with a screensaver and will redisplay the GDM login screen so a second user can log in. This feature is only available on systems that support virtual terminals and have them enabled. This feature is useful if you are logged in as user A, and user B wants to log in quickly but user A does not wish to log out. The X server takes care of the virtual terminal switching so it works transparently. If there is more than one running display defined with flexible=true, then the user is shown a dialog that displays the currently running sessions. The user can then pick which session to continue and will normally have to enter the password to unlock the screen.

Nested displays works on systems that do not support virtual terminals. This option starts a flexible display in a window in the current session. This does not lock the current session, so is not as secure as a flexible server started via virtual terminals.

The gdmflexiserver --command option provides a way to send commands to the GDM daemon and can be used to debug problems or to change the GDM configuration.

In addition to the following options, gdmflexiserver also supports standard GNOME options.

gdmdynamic allows the management of displays in a dynamic fashion. It is typically used in environments where it is not possible to list the possible displays in the GDM configuration files. The gdmdynamic command can be used to create a new display on a particular display number, run all newly created displays, or remove a display. The gdmdynamic command can also be used to list all attached displays or only those attached displays that match a pattern. The -a option is used to add a display, the -r option is used to run (or release) a display, the -d option is used to delete a display, and the -l option lists existing displays. Only one of these four options can be specified at a time, so in the life cycle of a particular display, the command will be run once to add, again to release (run) the display, and finally to delete when the session is to be terminated.

This program is designed to manage multiple simultaneous requests and tries to avoid flooding the daemon with requests. If the sockets connection is busy, it will sleep and retry a certain number of times that can be tuned with the -s and -t options.

Allows the user to select an image that will be used as the user's photo by GDM's face browser, if enabled by GDM. The selected file is stored as ~/.face. This command accepts standard GNOME options.

gdmthemetester takes two parameters. The first parameter specifies the environment and the second parameter specifies the path name or the name of a theme to view. This is a tool for viewing a theme outside of GDM. It is useful for testing or viewing themes. gdmthemetester requires that the system support gdmXnest. Note that themes can display differently depending on the theme's "Show mode". gdmthemetester allows viewing the themes in different modes via the environment option. Valid environment values and their meanings follow:

console       - In console mode.
console-timed - In console non-flexi mode.
flexi         - In flexi mode.
xdmcp         - In remote (XDMCP) mode.
remote-flexi  - In remote (XDMCP) & flexi mode.

The gdm command is really just a script which runs the gdm-binary, passing along any options. Before launching gdm-binary, the gdm wrapper script will source the <etc>/profile file to set the standard system environment variables. In order to better support internationalization, it will also set the LC_MESSAGES environment variable to LANG if neither LC_MESSAGES or LC_ALL are set. If you really need to set some additional environment before launching GDM, you can do so in this script.

gdmsetup runs a graphical application for modifying the GDM configuration file. Normally on systems that support the PAM userhelper, this is setup such that when you run gdmsetup as an ordinary user, it will first ask you for your root password before starting. Otherwise, this application may only be run as root. This application supports standard GNOME options.

gdm-restart stops and restarts GDM by sending the GDM daemon a HUP signal. This command will immediately terminate all sessions and log out users currently logged in with GDM.

gdm-safe-restart stops and restarts GDM by sending the GDM daemon a USR1 signal. GDM will be restarted as soon as all users log out.

gdm-stop stops GDM by sending the GDM daemon a TERM signal.

The gdmgreeter and gdmlogin are two different login applications, either can be used by GDM. gdmgreeter is themeable with GDM themes while gdmlogin is themable with GTK+ themes. These applications are normally executed by the GDM daemon. Both commands support standard GNOME options.

The gdmchooser is the XDMCP chooser application. The gdmchooser is normally executed by the GDM daemon. It supports the following options for XDM compatibility. This command supports standard GNOME options.

The gdm-ssh-session is normally executed by the GDM daemon when starting a secure remote connection through ssh. It does not take any options.