Given two directory trees, how can I find out which files differ?

Question

If I want find the differences between two directory trees, I usually just execute: diff -r dir1/ dir2/ This outputs exactly what the differences are between corresponding files. I'm interested in just getting a list of corresponding files whose content differs. I assumed that this would simply be a matter of passing a command line option to `diff`, but I couldn't find anything on the man page. Any suggestions?

Answer 1

The command meld can do such a recursive comparison.

Unix prompt> meld dir1 dir2

It brings up a window with two panes: one for each directory. It shows files changed at each directory level, and if you click on a specific file it shows tkdiff like differences of the file in two different trees.