Gtk.Socket.prototype.get_id

function get_id():xlib.Window {
    // Gjs wrapper for gtk_socket_get_id()
}

Gets the window ID of a Gtk.Socket widget, which can then be used to create a client embedded inside the socket, for instance with Gtk.Plug.new.

The Gtk.Socket must have already be added into a toplevel window before you can make this call.