-The output format from "git-diff-index", "git-diff-tree" and
-"git-diff-files" are very similar.
+The output format from "git-diff-index", "git-diff-tree",
+"git-diff-files" and "git diff --raw" are very similar.
-These commands all compare two sets of things; what is
+These commands all compare two sets of things; what is
compared differs:
git-diff-index <tree-ish>::
in pathnames are represented as `\t`, `\n`, and `\\`,
respectively.
+diff format for merges
+----------------------
-Generating patches with -p
---------------------------
-
-When "git-diff-index", "git-diff-tree", or "git-diff-files" are run
-with a '-p' option, they do not produce the output described above;
-instead they produce a patch file.
-
-The patch generation can be customized at two levels.
-
-1. When the environment variable 'GIT_EXTERNAL_DIFF' is not set,
- these commands internally invoke "diff" like this:
-
- diff -L a/<path> -L b/<path> -pu <old> <new>
-+
-For added files, `/dev/null` is used for <old>. For removed
-files, `/dev/null` is used for <new>
-+
-The "diff" formatting options can be customized via the
-environment variable 'GIT_DIFF_OPTS'. For example, if you
-prefer context diff:
-
- GIT_DIFF_OPTS=-c git-diff-index -p HEAD
-
-
-2. When the environment variable 'GIT_EXTERNAL_DIFF' is set, the
- program named by it is called, instead of the diff invocation
- described above.
-+
-For a path that is added, removed, or modified,
-'GIT_EXTERNAL_DIFF' is called with 7 parameters:
-
- path old-file old-hex old-mode new-file new-hex new-mode
-+
-where:
-
- <old|new>-file:: are files GIT_EXTERNAL_DIFF can use to read the
- contents of <old|new>,
- <old|new>-hex:: are the 40-hexdigit SHA1 hashes,
- <old|new>-mode:: are the octal representation of the file modes.
-
-+
-The file parameters can point at the user's working file
-(e.g. `new-file` in "git-diff-files"), `/dev/null` (e.g. `old-file`
-when a new file is added), or a temporary file (e.g. `old-file` in the
-index). 'GIT_EXTERNAL_DIFF' should not worry about unlinking the
-temporary file --- it is removed when 'GIT_EXTERNAL_DIFF' exits.
-
-For a path that is unmerged, 'GIT_EXTERNAL_DIFF' is called with 1
-parameter, <path>.
-
-
-git specific extension to diff format
--------------------------------------
-
-What -p option produces is slightly different from the
-traditional diff format.
-
-1. It is preceeded with a "git diff" header, that looks like
- this:
-
- diff --git a/file1 b/file2
-+
-The `a/` and `b/` filenames are the same unless rename/copy is
-involved. Especially, even for a creation or a deletion,
-`/dev/null` is _not_ used in place of `a/` or `b/` filenames.
-+
-When rename/copy is involved, `file1` and `file2` show the
-name of the source file of the rename/copy and the name of
-the file that rename/copy produces, respectively.
-
-2. It is followed by one or more extended header lines:
-
- old mode <mode>
- new mode <mode>
- deleted file mode <mode>
- new file mode <mode>
- copy from <path>
- copy to <path>
- rename from <path>
- rename to <path>
- similarity index <number>
- dissimilarity index <number>
- index <hash>..<hash> <mode>
-
-3. TAB, LF, and backslash characters in pathnames are
- represented as `\t`, `\n`, and `\\`, respectively.
+"git-diff-tree", "git-diff-files" and "git-diff --raw"
+can take '-c' or '--cc' option
+to generate diff output also for merge commits. The output differs
+from the format described above in the following way:
+
+. there is a colon for each parent
+. there are more "src" modes and "src" sha1
+. status is concatenated status characters for each parent
+. no optional "score" number
+. single path, only for "dst"
+
+Example:
+
+------------------------------------------------
+::100644 100644 100644 fabadb8... cc95eb0... 4866510... MM describe.c
+------------------------------------------------
+
+Note that 'combined diff' lists only files which were modified from
+all parents.
+
+
+include::diff-generate-patch.txt[]