How do I configure git to use a different tool for diffing with the .gitconfig file. I have this in my .gitconfig:
tool = git-chdiff #also tried /bin/git-chdiff
Git offers a range of difftools pre-configured "out-of-the-box" (kdiff3, kompare, tkdiff, meld, xxdiff, emerge, vimdiff, gvimdiff, ecmerge, diffuse, opendiff, p4merge and araxis), and also allows you to specify your own. To use one of the pre-configured difftools (for example, "vimdiff"), you add the following lines to your
[diff] tool = vimdiff
Specifying your own difftool, on the other hand, takes a little bit more work, see here and here How do I view 'git diff' output with visual diff program?