git - Configuring diff tool with .gitconfig

Question

How do I configure Git to use a different tool for diffing with the .gitconfig file?

I have this in my .gitconfig:

[diff]
    tool = git-chdiff #also tried /bin/git-chdiff

It does not work; it just opens the regular command line diff. When I do

export GIT_EXTERNAL_DIFF=git-chdiff

then git diff will open up the external diffing tool (so I know the external diff tool script works fine). Do I have something wrong with my .gitconfig configuration for the diff tool?

Answer 1

An additional way to do that (from the command line):

git config --global diff.tool tkdiff
git config --global merge.tool tkdiff
git config --global --add difftool.prompt false

The first two lines will set the difftool and mergetool to tkdiff- change that according to your preferences. The third line disables the annoying prompt so whenever you hit git difftool it will automatically launch the difftool.