"git log" with the "-p" option, they
do not produce the output described above; instead they produce a
patch file. You can customize the creation of such patches via the
-GIT_EXTERNAL_DIFF and the GIT_DIFF_OPTS environment variables.
+`GIT_EXTERNAL_DIFF` and the `GIT_DIFF_OPTS` environment variables.
What the -p option produces is slightly different from the traditional
diff format:
Any diff-generating command can take the `-c` or `--cc` option to
produce a 'combined diff' when showing a merge. This is the default
format when showing merges with linkgit:git-diff[1] or
-linkgit:git-show[1]. Note also that you can give the `-m' option to any
+linkgit:git-show[1]. Note also that you can give the `-m` option to any
of these commands to force generation of diffs with individual parents
of a merge.
In the above example output, the function signature was changed
from both files (hence two `-` removals from both file1 and
file2, plus `++` to mean one line that was added does not appear
-in either file1 nor file2). Also eight other lines are the same
+in either file1 or file2). Also eight other lines are the same
from file1 but do not appear in file2 (hence prefixed with `+`).
When shown by `git diff-tree -c`, it compares the parents of a