Check out what Anders Lindgren did with rdebug-shortkey-mode for rdebug

On Fri, Nov 6, 2009 at 11:57 AM, Dan Nicolaescu <dann@ics.uci.edu> wrote:
Rocky Bernstein <rocky@gnu.org> writes:

 > I have started to rewrite gud from the ground up.

Another thing you might want to consider in the design is to allow
debugger interaction with simple key bindings from file buffers.

Now to send commands to the debugger you'd have to use the *gud* buffer,
or use complicated key bindings.
Compare to how `edebug' works, the buffer is made read-only, and simple
bindings like: n c d  can be used.