Documentation/config/difftool.txt

   1 difftool.<tool>.path::
   2         Override the path for the given tool.  This is useful in case
   3         your tool is not in the PATH.
   4
   5 difftool.<tool>.cmd::
   6         Specify the command to invoke the specified diff tool.
   7         The specified command is evaluated in shell with the following
   8         variables available:  'LOCAL' is set to the name of the temporary
   9         file containing the contents of the diff pre-image and 'REMOTE'
  10         is set to the name of the temporary file containing the contents
  11         of the diff post-image.
  12
  13 difftool.prompt::
  14         Prompt before each invocation of the diff tool.