+
+
+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.