RFC: Remote Terminal Multiplexer Protocol
This document describes a protocol for a remote terminal session, which
may have 0 or more active terminals, to exchange control information with
a local terminal renderer. This is similar in spirit to the
Control Mode functionality but is spec'd out separately from tmux in
order to make it relatively tmux agnostic and thus potentially easier
for it to be integrated in alternative multiplexer implementations
and supported in more terminal emulators.