get_screen_for_root

Gets the Screen for the root window at root_window_id, or null if no Screen exists for this root window.

This function does not work if get_screen was not called for the sought Screen before, and returns null.

Parameters:

this	a Handle
root_window_id	an X window ID.

Returns:

the Screen for the root window at root_window_id, or null . The returned Screen is owned by Handle and must not be referenced or unreferenced.