- `pascal` suitable for source code in the Pascal/Delphi language.
+- `perl` suitable for source code in the Perl language.
+
- `php` suitable for source code in the PHP language.
- `python` suitable for source code in the Python language.
manually with `git update-ref -d refs/notes/textconv/jpg` (where
"jpg" is the name of the diff driver, as in the example above).
+Choosing textconv versus external diff
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+If you want to show differences between binary or specially-formatted
+blobs in your repository, you can choose to use either an external diff
+command, or to use textconv to convert them to a diff-able text format.
+Which method you choose depends on your exact situation.
+
+The advantage of using an external diff command is flexibility. You are
+not bound to find line-oriented changes, nor is it necessary for the
+output to resemble unified diff. You are free to locate and report
+changes in the most appropriate way for your data format.
+
+A textconv, by comparison, is much more limiting. You provide a
+transformation of the data into a line-oriented text format, and git
+uses its regular diff tools to generate the output. There are several
+advantages to choosing this method:
+
+1. Ease of use. It is often much simpler to write a binary to text
+ transformation than it is to perform your own diff. In many cases,
+ existing programs can be used as textconv filters (e.g., exif,
+ odt2txt).
+
+2. Git diff features. By performing only the transformation step
+ yourself, you can still utilize many of git's diff features,
+ including colorization, word-diff, and combined diffs for merges.
+
+3. Caching. Textconv caching can speed up repeated diffs, such as those
+ you might trigger by running `git log -p`.
+
+
+Marking files as binary
+^^^^^^^^^^^^^^^^^^^^^^^
+
+Git usually guesses correctly whether a blob contains text or binary
+data by examining the beginning of the contents. However, sometimes you
+may want to override its decision, either because a blob contains binary
+data later in the file, or because the content, while technically
+composed of text characters, is opaque to a human reader. For example,
+many postscript files contain only ascii characters, but produce noisy
+and meaningless diffs.
+
+The simplest way to mark a file as binary is to unset the diff
+attribute in the `.gitattributes` file:
+
+------------------------
+*.ps -diff
+------------------------
+
+This will cause git to generate `Binary files differ` (or a binary
+patch, if binary patches are enabled) instead of a regular diff.
+
+However, one may also want to specify other diff driver attributes. For
+example, you might want to use `textconv` to convert postscript files to
+an ascii representation for human viewing, but otherwise treat them as
+binary files. You cannot specify both `-diff` and `diff=ps` attributes.
+The solution is to use the `diff.*.binary` config option:
+
+------------------------
+[diff "ps"]
+ textconv = ps2ascii
+ binary = true
+------------------------
+
Performing a three-way merge
~~~~~~~~~~~~~~~~~~~~~~~~~~~~
`merge`
^^^^^^^
-The attribute `merge` affects how three versions of a file is
+The attribute `merge` affects how three versions of a file are
merged when a file-level merge is necessary during `git merge`,
and other commands such as `git revert` and `git cherry-pick`.
Take the version from the current branch as the
tentative merge result, and declare that the merge has
- conflicts. This is suitable for binary files that does
+ conflicts. This is suitable for binary files that do
not have a well-defined merge semantics.
Unspecified::
By default, this uses the same built-in 3-way merge
- driver as is the case the `merge` attribute is set.
- However, `merge.default` configuration variable can name
- different merge driver to be used for paths to which the
+ driver as is the case when the `merge` attribute is set.
+ However, the `merge.default` configuration variable can name
+ different merge driver to be used with paths for which the
`merge` attribute is unspecified.
String::