weston - Man Page

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 kiosk shell.

Weston also supports X clients via Xwayland, see below.

Backends

drm: 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.
wayland: 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.
x11: 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.
rdp: The RDP backend runs in memory without the need of graphical hardware. Access to the desktop is done by using the RDP protocol. Each connecting client has its own seat making it a cheap way to test multi-seat support. See weston-rdp(7), if installed.
vnc: The VNC backend runs in memory without the need of graphical hardware. Access to the desktop is done by using the RFB protocol. Currently only one connecting client is supported. See weston-vnc(7), if installed.
pipewire: The PipeWire backend runs in memory without the need of graphical hardware and creates a PipeWire node for each output. It can be used to capture Weston outputs for processing with another application.
headless: The headless backend runs in memory. It can be used to capture Weston outputs or to test client applications.

Shells

Weston's user interface is implemented by individual 'shell' plugins. A number of shells are provided for different usecases.

desktop: The desktop shell is Weston's default mode. It provides an example of a desktop-like environment, featuring a panel with launchers and a clock, a background, and an interactive task switcher. Whilst not intended to be a full-fledged desktop environment in and of itself, it is an example of how such an environment can be built.
kiosk: The kiosk shell is intended for environments which want to run a single application at a time. Applications will be made full screen and activated as they are started.
fullscreen: The fullscreen shell is a deprecated implementation of the ideas behind the kiosk shell. It requires specific client support for the zwp_fullscreen_shell_v1 interface.
ivi: The IVI shell is a special-purpose shell which exposes an API compatible with the GENIVI Layer Manager to user-provided HMI controller modules. It is intended for use in automotive environments.

Xwayland

Weston can support X11 clients running within a Weston session via an X server called Xwayland. Xwayland is built as a separate executable, provided by X.Org. Once built and installed, it can be activated with the --xwayland option. Weston will listen on a new X11 display socket and export it through the DISPLAY environment variable.

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.

Options

Weston core options

-Bbackend1,backend2, --backend=backend1,backend2

Load the comma-separated list of backends instead of the default backend, see Backends. The backend modules are searched for in /usr/lib64/weston. The default backend is drm unless the environment suggests otherwise, see DISPLAY and WAYLAND_DISPLAY. The first backend is the primary backend, and it provides the renderer. Not all backends support being loaded as secondary backends, which reuse the primary backend's renderer.

-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). This option is ignored if the --no-config option is passed.

--debug

Enable debug protocol extension weston_debug_v1 which any client can use to receive debugging messages from the compositor.

WARNING: This is risky for two reasons. First, a client may cause a denial-of-service blocking the compositor by providing an unsuitable file descriptor, and second, the debug messages may expose sensitive information. Additionally this will expose weston-screenshooter interface allowing the user to take screenshots of the outputs using weston-screenshooter application, which can lead to silently leaking the output contents. This option should not be used in production.

-fscope1,scope2, --flight-rec-scopes=scope1,scope2

Specify to which scopes should subscribe to. Useful to control which streams to write data into the flight recorder. Flight recorder has limited space, once the flight recorder is full new data will overwrite the old data. Without any scopes specified, it subscribes to 'log' and 'drm-backend' scopes. Passing an empty value would disable the flight recorder entirely.

-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.

--log=file.log

Append log messages to the file file.log instead of writing them to stderr.

-lscope1,scope2, --logger-scopes=scope1,scope2

Specify to which log scopes should subscribe to. When no scopes are supplied, the log "log" scope will be subscribed by default. Useful to control which streams to write data into the logger and can be helpful in diagnosing early start-up code.

--modules=module1.so,module2.so

Load the comma-separated list of modules. Only used by the test suite. The file is searched for in /usr/lib64/weston, or you can pass an absolute path.

--no-config

Do not read weston.ini for the compositor. Avoids e.g. loading compositor modules via the configuration file, which is useful for unit tests.

--renderer=renderer

Select which renderer to use for Weston's internal composition. Defaults to automatic selection.

--shell=shell

Select which shell to load to provide Weston's user interface. See Environment.

-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. --version Print the program version.

--wait-for-debugger

Raises SIGSTOP before initializing the compositor. This allows the user to attach with a debugger and continue execution by sending SIGCONT. This is useful for debugging a crash on start-up when it would be inconvenient to launch weston directly from a debugger. There is also a weston.ini option to do the same.

--xwayland

Support X11 clients through the Xwayland server.

DRM backend options

See weston-drm(7).

Wayland backend options

--display=display: Name of the Wayland display to connect to, see also WAYLAND_DISPLAY of the environment.
--fullscreen: Create a single fullscreen output
--output-count=N: Create N Wayland windows to emulate the same number of outputs.
--width=W, --height=H: Make all outputs have a size of WxH pixels.
--scale=N: Give all outputs a scale factor of N.
--use-pixman: Deprecated in favour of the --renderer option. 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

--fullscreen
--no-input: Do not provide any input devices. Used for testing input-less Weston.
--output-count=N: 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.
--scale=N: Give all outputs a scale factor of N.
--use-pixman: Deprecated in favour of the --renderer option. 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.

RDP backend options

See weston-rdp(7).

VNC backend options

See weston-vnc(7).

headless backend options

--width=W, --height=H: Make the default size of each output WxH pixels.
--scale=N: Give all outputs a scale factor of N.
--transform=transform: Transform for the output, which can be rotated in 90-degree steps and possibly flipped. Possible values are normal, rotate-90, rotate-180, rotate-270, flipped, flipped-rotate-90, flipped-rotate-180, and flipped-rotate-270.
--no-outputs: Do not create any virtual outputs.
--refresh-rate=N: Give all outputs a refresh rate of N mHz (60,000 mHz by default). Supported values range from 0 mHz to 1,000,000 mHz. 0 is a special value that repaints as soon as possible on capture requests only, not on damages.

Files

If the environment variable is set, the configuration file is read from the respective path.

$XDG_CONFIG_HOME/weston.ini
$HOME/.config/weston.ini

Environment

DISPLAY

The X display. If DISPLAY is set, and WAYLAND_DISPLAY is not set, the default backend becomes x11.

WAYLAND_DEBUG

If set to any value, causes libwayland to print the live protocol to stderr.

WAYLAND_DISPLAY

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. This allows launching Weston as a nested server.

WAYLAND_SOCKET

For Wayland clients, holds the file descriptor of an open local socket to a Wayland server.

WESTON_CONFIG_FILE

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.

XCURSOR_PATH

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).

XCURSOR_SIZE

This variable can be set for choosing an specific size of cursor. Affect Wayland and X11 clients. See xcursor (3).

XDG_CONFIG_HOME

If set, specifies the directory where to look for weston.ini.

XDG_RUNTIME_DIR

The directory for Weston's socket and lock files. Wayland clients will automatically use this.

Program Execution

It is possible to execute a program that will be run by Weston.

By using this syntax :: weston [options] -- [program [arguments]]

The '--' here is mandatory to execute a program. There are examples in the Examples section.

Launch Weston with the DRM backend on a VT: weston
Launch Weston with the DRM backend and XWayland support: weston --xwayland
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: weston
Launch Weston and make it start weston-terminal: weston -- /usr/local/bin/weston-terminal
Launch Weston with the kiosk shell and make it start weston-simple-egl: weston --shell=kiosk-shell.so -- /usr/local/bin/weston-simple-egl
Launch Weston with the kiosk shell and open a pdf document with mupdf: weston --shell=kiosk-shell.so -- mupdf /home/user/Documents/krh/wayland.pdf

Referenced By

wayland-info(1), waypipe(1), weston-bindings(7), weston-drm(7), weston.ini(5), weston-rdp(7), weston-vnc(7), wlheadless-run(1).

2019-03-23 Weston 14.0.0