gtk2/docs/reference/gtk/wayland.md

Title: Using GTK with Wayland Slug: gtk-wayland

The GDK Wayland backend provides support for running GTK applications under a Wayland compositor. To run your application in this way, select the Wayland backend by setting GDK_BACKEND=wayland.

On UNIX, the Wayland backend is enabled by default, so you don't need to do anything special when compiling it, and everything should "just work."

Wayland-specific environment variables

WAYLAND_DISPLAY

Specifies the name of the Wayland display to use. Typically, wayland-0 or wayland-1.

XDG_RUNTIME_DIR

Used to locate the Wayland socket to use.

Wayland-specific APIs

See the documentation for Wayland-specific GDK APIs.