Wayland

Wayland is a new display protocol that aims to replace X11. Wayland requires a seat manager to work.

The setup-wayland-base script installs and enables elogind as seat manager besides enabling community repository and eudev.

Compositors

Display servers that implement the Wayland display server protocol are also called Wayland compositors because they additionally perform the task of a compositing window manager.

Multiple compositor implementations exist, including Sway, Mutter (GNOME's compositor) and Kwin (KDE's compositor). The following compositors are available in Alpine Linux.

XDG_RUNTIME_DIR

As per the protocol spec, Wayland compositors require the XDG_RUNTIME_DIR variable to be set.

With elogind

When using elogind as a seat manager, it exports XDG_RUNTIME_DIR and other XDG environment variables automatically for each session. No further configuration is required.

With pam_rundir

pam_rundir is a PAM module that provides the runtime directory variable. Installing the package pam-rundir takes care of dependencies and no further configuration is required.

Note: XDG_RUNTIME_DIR variable MUST be initialised before the Wayland compositor, and also before the D-Bus session instance is started in your startup script/file for both the methods listed below.

With mkrundir

mkrundir is an executable that can be used to initialise the runtime directory explicitly by each user. To use mkrundir, install the package mkrundir available in testing repository. In your shell init script (e.g.: ~/.profile include an entry as follows at the top of the file

Contents of ~.profile

...
export XDG_RUNTIME_DIR=$(mkrundir)
...

As per mkrundir website, this might have issues inside containers, due to privilege escalation.

Creating and exporting XDG_RUNTIME_DIR manually

Generally, care should be taken when configuring the XDG_* variables manually as this configuration may have errors or conflict with other utilities that do this automatically. Use this only on a system that's not using elogind and other solutions outlined above cannot handle this.

The XDG_RUNTIME_DIR can be initialised manually by adding below snippet to shell init scripts (e.g.: ~/.profile):

Contents of ~/.profile

if [ -z "$XDG_RUNTIME_DIR" ]; then
	XDG_RUNTIME_DIR="/tmp/$(id -u)-runtime-dir"

	mkdir -pm 0700 "$XDG_RUNTIME_DIR"
	export XDG_RUNTIME_DIR
fi