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git difftool

git difftool uses git diff to get differences, but displays them using common diff tools.

These «common diff tools» can be queried with

git difftool --tool-help

git difftool accepts the same options and arguments as git diff

Specifying the executable to be run

Start gvim in diff mode for each file that has changed between the commits that are identified with 2a532db and 5949ddb:

git difftool --no-prompt --extcmd="gvim.exe -d"  2a532db 5949ddb

Seems like it's doing the same as above:

git difftool --no-prompt --tool  gvimdiff 2a532db 5949ddb

The default value for the --tool option can be configured with the diff.tool option:

git config --global diff.tool gvimdiff

Do not prompt before starting the executable to show a difference (as though --no-prompt was used when invoking git difftool):

git config --global difftool.prompt false

git difftool --dir-diff --tool=… HEAD~ HEAD