opening new diffs in existing window

["Kacper Wysocki" <kacperw online no>]

Hello all,
I really like meld for visual diffing, but I often have several files
diffed at the same time, so it would be very helpful to have new diffs
open in an existing meld window - something that for example gedit
currently does. To be precise, I would like meld to check, on startup,
if there's another instance open already and if it is, open the
requested diff in a new tab in the existing window. What's great is
that meld already has tabs - all we need to do is check for an
existing instance on startup, and pass it the arguments.

I've tried looking at the meld source and what gedit does, but the
truth is I do not have much experience with gtk. My question is:
What would be the best way to have meld detect and communicate with an
existing instance? Shared memory, unix domain sockets, message queues,
a pid file or dbus? Or does GTK itself have a facility for doing this?
Where would such a change fit the best?

I'm hoping there are some experienced developers on this list that
will be able to point me in the right direction, and that my questions
aren't too general or vague to be answered..

TIA,
-Kacper