weston(1) the reference Wayland server




weston is the reference implementation of a Wayland server. A Wayland server is a display server, a window manager, and a compositor all in one. Weston has several backends as loadable modules: it can run on Linux KMS (kernel modesetting via DRM), as an X client, or inside another Wayland server instance.

Weston supports fundamentally different graphical user interface paradigms via shell plugins. Two plugins are provided: the desktop shell, and the tablet shell.

When weston is started as the first windowing system (i.e. not under X nor under another Wayland server), it should be done with the command weston-launch to set up proper privileged access to devices.

Weston also supports X clients via XWayland, see below.


The DRM backend uses Linux KMS for output and evdev devices for input. It supports multiple monitors in a unified desktop with DPMS. See weston-drm(7), if installed.
The Wayland backend runs on another Wayland server, a different Weston instance, for example. Weston shows up as a single desktop window on the parent server.
The X11 backend runs on an X server. Each Weston output becomes an X window. This is a cheap way to test multi-monitor support of a Wayland shell, desktop, or applications.


Each of these shells have its own public protocol interface for clients. This means that a client must be specifically written for a shell protocol, otherwise it will not work.
Desktop shell
Desktop shell is like a modern X desktop environment, concentrating on traditional keyboard and mouse user interfaces and the familiar desktop-like window management. Desktop shell consists of the shell plugin desktop-shell.so and the special client weston-desktop-shell which provides the wallpaper, panel, and screen locking dialog.
Fullscreen shell
Fullscreen shell is intended for a client that needs to take over whole outputs, often all outputs. This is primarily intended for running another compositor on Weston. The other compositor does not need to handle any platform-specifics like DRM/KMS or evdev/libinput. The shell consists only of the shell plugin fullscreen-shell.so.
In-vehicle infotainment shell is a special purpose shell that exposes a GENIVI Layer Manager compatible API to controller modules, and a very simple shell protocol towards clients. IVI-shell starts with loading ivi-shell.so, and then a controller module which may launch helper clients.


XWayland requires a special X.org server to be installed. This X server will connect to a Wayland server as a Wayland client, and X clients will connect to the X server. XWayland provides backwards compatibility to X applications in a Wayland stack.

XWayland is activated by instructing weston to load xwayland.so module, see EXAMPLES. Weston starts listening on a new X display socket, and exports it in the environment variable DISPLAY. When the first X client connects, Weston launches a special X server as a Wayland client to handle the X client and all future X clients.

It has also its own X window manager where cursor themes and sizes can be chosen using XCURSOR_PATH and XCURSOR_SIZE environment variables. See ENVIRONMENT.


Weston core options:

-Bbackend.so, --backend=backend.so
Load backend.so instead of the default backend. The file is searched for in /usr/lib/x86_64-linux-gnu/weston, or you can pass an absolute path. The default backend is drm-backend.so unless the environment suggests otherwise, see DISPLAY and WAYLAND_DISPLAY.
-cconfig.ini, --config=config.ini
Load config.ini instead of weston.ini. The argument can also be an absolute path starting with a /. If the path is not absolute, it will be searched in the normal config paths, see weston.ini(5). If also --no-config is given, no configuration file will be read.
Print the program version.
-h, --help
Print a summary of command line options, and quit.
-iN, --idle-time=N
Set the idle timeout to N seconds. The default timeout is 300 seconds. When there has not been any user input for the idle timeout, Weston enters an inactive mode. The screen fades to black, monitors may switch off, and the shell may lock the session. A value of 0 effectively disables the timeout.
Append log messages to the file file.log instead of writing them to stderr.
Load the comma-separated list of modules. Only used by the test suite. The file is searched for in /usr/lib/x86_64-linux-gnu/weston, or you can pass an absolute path.
Do not read weston.ini for the compositor. Avoids e.g. loading compositor modules via the configuration file, which is useful for unit tests.
-Sname, --socket=name
Weston will listen in the Wayland socket called name. Weston will export WAYLAND_DISPLAY with this value in the environment for all child processes to allow them to connect to the right server automatically.

DRM backend options:

See weston-drm(7).

Wayland backend options:

Name of the Wayland display to connect to, see also WAYLAND_DISPLAY of the environment.
Create a single fullscreen output
Create N Wayland windows to emulate the same number of outputs.
--width=W, --height=H
Make all outputs have a size of WxH pixels.
Give all outputs a scale factor of N.
Use the pixman renderer. By default, weston will try to use EGL and GLES2 for rendering and will fall back to the pixman-based renderer for software compositing if EGL cannot be used. Passing this option will force weston to use the pixman renderer.

X11 backend options:

Do not provide any input devices. Used for testing input-less Weston.
Create N X windows to emulate the same number of outputs.
--width=W, --height=H
Make the default size of each X window WxH pixels.
Give all outputs a scale factor of N.
Use the pixman renderer. By default weston will try to use EGL and GLES2 for rendering. Passing this option will make weston use the pixman library for software compsiting.


If the environment variable is set, the configuration file is read from the respective path, or the current directory if neither is set.



The X display. If DISPLAY is set, and WAYLAND_DISPLAY is not set, the default backend becomes x11-backend.so.
If set to any value, causes libwayland to print the live protocol to stderr.
The name of the display (socket) of an already running Wayland server, without the path. The directory path is always taken from XDG_RUNTIME_DIR. If WAYLAND_DISPLAY is not set, the socket name is "wayland-0".

If WAYLAND_DISPLAY is already set, the default backend becomes wayland-backend.so. This allows launching Weston as a nested server.

For Wayland clients, holds the file descriptor of an open local socket to a Wayland server.
Weston sets this variable to the absolute path of the configuration file it loads, or to the empty string if no file is used. Programs that use weston.ini will read the file specified by this variable instead, or do not read any file if it is empty. Unset variable causes falling back to the default name weston.ini.
Set the list of paths to look for cursors in. It changes both libwayland-cursor and libXcursor, so it affects both Wayland and X11 based clients. See xcursor (3).
This variable can be set for choosing an specific size of cursor. Affect Wayland and X11 clients. See xcursor (3).
If set, specifies the directory where to look for weston.ini.
The directory for Weston's socket and lock files. Wayland clients will automatically use this.


Weston has a segmentation fault handler, that attempts to restore the virtual console or ungrab X before raising SIGTRAP. If you run weston under gdb(1) from an X11 terminal or a different virtual terminal, and tell gdb
handle SIGSEGV nostop

This will allow weston to switch back to gdb on crash and then gdb will catch the crash with SIGTRAP.


Bugs should be reported to the freedesktop.org bugzilla at https://bugs.freedesktop.org with product "Wayland" and component "weston".


Launch Weston with the DRM backend on a VT
Launch Weston with the DRM backend and XWayland support
weston-launch -- --modules=xwayland.so
Launch Weston (wayland-1) nested in another Weston instance (wayland-0)
WAYLAND_DISPLAY=wayland-0 weston -Swayland-1
From an X terminal, launch Weston with the x11 backend