RLogin needs a keep-alive or GA or similar scheme
RLogin connections (at least on Windows) can go hours without being notice that they've been terminated. If the inactivity timeouts are disable for the user (e.g. H-restriction) or there's just no need for the server to send any text, that can mean that the node remains "in-use" indefinitely. If we could send a "GA" or something similar to how we do it for Telnet (e.g. OOB request for 'ss' (screen size)), the TCP session should notice it's disconnected and terminate gracefully. Look into urgent/OOB send for Rlogin.