gdk_window_set_urgency_hint is not implemented on quartz
Submitted by Christian Hergert
Assigned to gtk-quartz maintainers
The GdkWindow backend for quartz currently does not implement gdk_window_set_urgency_hint().
This should be set using NSApplication:requestUserAttention.
In NSApplication, there are currently two attention types, information and critical. Information will go away after 1 second wile critical will stay until the application gets focus.
To map closest to the implementation in X, I'd suggest the critical attention type.