I've been hacking on a directory comparison and sync front end in Emacs that uses rsync, diff, cmp, and Ediff to do all its comparison and syncing under the hood. Its primary differentiation vs. Ediff alone is a flat view of all the differing files in a directory tree, rather than Ediff's single directory per session.

If you'd like to give it a try, clone the code from https://github.com/matthewlmcclure/dircmp-mode, load dircmp.el, and M-x compare-directories.

I'd value any feedback you have, good or bad.

Matt

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Matt McClure
http://www.matthewlmcclure.com
http://www.mapmyfitness.com/profile/matthewlmcclure