SYNOPSIS
--------
-$GIT_DIR/info/attributes, gitattributes
+$GIT_DIR/info/attributes, .gitattributes
DESCRIPTION
These attributes affect how the contents stored in the
repository are copied to the working tree files when commands
-such as `git checkout` and `git merge` run. They also affect how
+such as 'git-checkout' and 'git-merge' run. They also affect how
git stores the contents you prepare in the working tree in the
-repository upon `git add` and `git commit`.
+repository upon 'git-add' and 'git-commit'.
`crlf`
^^^^^^
Unset::
- Unsetting the `crlf` attribute on a path is meant to
- mark the path as a "binary" file. The path never goes
- through line endings conversion upon checkin/checkout.
+ Unsetting the `crlf` attribute on a path tells git not to
+ attempt any end-of-line conversion upon checkin or checkout.
Unspecified::
a conversion done to the files in the work tree, but there are a
few exceptions. Even though...
-- "git add" itself does not touch the files in the work tree, the
+- 'git-add' itself does not touch the files in the work tree, the
next checkout would, so the safety triggers;
-- "git apply" to update a text file with a patch does touch the files
+- 'git-apply' to update a text file with a patch does touch the files
in the work tree, but the operation is about text files and CRLF
conversion is about fixing the line ending inconsistencies, so the
safety does not trigger;
-- "git diff" itself does not touch the files in the work tree, it is
- often run to inspect the changes you intend to next "git add". To
+- 'git-diff' itself does not touch the files in the work tree, it is
+ often run to inspect the changes you intend to next 'git-add'. To
catch potential problems early, safety triggers.
`ident`
^^^^^^^
-When the attribute `ident` is set to a path, git replaces
-`$Id$` in the blob object with `$Id:`, followed by
+When the attribute `ident` is set for a path, git replaces
+`$Id$` in the blob object with `$Id:`, followed by the
40-character hexadecimal blob object name, followed by a dollar
sign `$` upon checkout. Any byte sequence that begins with
`$Id:` and ends with `$` in the worktree file is replaced
Generating diff text
~~~~~~~~~~~~~~~~~~~~
-The attribute `diff` affects if `git diff` generates textual
-patch for the path or just says `Binary files differ`. It also
-can affect what line is shown on the hunk header `@@ -k,l +n,m @@`
-line.
+`diff`
+^^^^^^
+
+The attribute `diff` affects how 'git' generates diffs for particular
+files. It can tell git whether to generate a textual patch for the path
+or to treat the path as a binary file. It can also affect what line is
+shown on the hunk header `@@ -k,l +n,m @@` line, tell git to use an
+external command to generate the diff, or ask git to convert binary
+files to a text format before generating the diff.
Set::
Unset::
A path to which the `diff` attribute is unset will
- generate `Binary files differ`.
+ generate `Binary files differ` (or a binary patch, if
+ binary patches are enabled).
Unspecified::
String::
- Diff is shown using the specified custom diff driver.
- The driver program is given its input using the same
- calling convention as used for GIT_EXTERNAL_DIFF
- program. This name is also used for custom hunk header
- selection.
+ Diff is shown using the specified diff driver. Each driver may
+ specify one or more options, as described in the following
+ section. The options for the diff driver "foo" are defined
+ by the configuration variables in the "diff.foo" section of the
+ git config file.
-Defining a custom diff driver
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Defining an external diff driver
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
The definition of a diff driver is done in `gitconfig`, not
`gitattributes` file, so strictly speaking this manual page is a
wrong place to talk about it. However...
-To define a custom diff driver `jcdiff`, add a section to your
+To define an external diff driver `jcdiff`, add a section to your
`$GIT_DIR/config` file (or `$HOME/.gitconfig` file) like this:
----------------------------------------------------------------
attribute set to `jcdiff`, it calls the command you specified
with the above configuration, i.e. `j-c-diff`, with 7
parameters, just like `GIT_EXTERNAL_DIFF` program is called.
-See linkgit:git[7] for details.
+See linkgit:git[1] for details.
Defining a custom hunk-header
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-Each group of changes (called "hunk") in the textual diff output
+Each group of changes (called a "hunk") in the textual diff output
is prefixed with a line of the form:
@@ -k,l +n,m @@ TEXT
-The text is called 'hunk header', and by default a line that
-begins with an alphabet, an underscore or a dollar sign is used,
-which matches what GNU `diff -p` output uses. This default
-selection however is not suited for some contents, and you can
-use customized pattern to make a selection.
+This is called a 'hunk header'. The "TEXT" portion is by default a line
+that begins with an alphabet, an underscore or a dollar sign; this
+matches what GNU 'diff -p' output uses. This default selection however
+is not suited for some contents, and you can use a customized pattern
+to make a selection.
-First in .gitattributes, you would assign the `diff` attribute
+First, in .gitattributes, you would assign the `diff` attribute
for paths.
------------------------
*.tex diff=tex
------------------------
-Then, you would define "diff.tex.funcname" configuration to
+Then, you would define a "diff.tex.xfuncname" configuration to
specify a regular expression that matches a line that you would
-want to appear as the hunk header, like this:
+want to appear as the hunk header "TEXT", like this:
------------------------
[diff "tex"]
- funcname = "^\\(\\\\\\(sub\\)*section{.*\\)$"
+ xfuncname = "^(\\\\(sub)*section\\{.*)$"
------------------------
Note. A single level of backslashes are eaten by the
There are a few built-in patterns to make this easier, and `tex`
is one of them, so you do not have to write the above in your
configuration file (you still need to enable this with the
-attribute mechanism, via `.gitattributes`). Another built-in
-pattern is defined for `java` that defines a pattern suitable
-for program text in Java language.
+attribute mechanism, via `.gitattributes`). The following built in
+patterns are available:
+
+- `bibtex` suitable for files with BibTeX coded references.
+
+- `cpp` suitable for source code in the C and C++ languages.
+
+- `html` suitable for HTML/XHTML documents.
+
+- `java` suitable for source code in the Java language.
+
+- `objc` suitable for source code in the Objective-C language.
+
+- `pascal` suitable for source code in the Pascal/Delphi language.
+
+- `php` suitable for source code in the PHP language.
+
+- `python` suitable for source code in the Python language.
+
+- `ruby` suitable for source code in the Ruby language.
+
+- `tex` suitable for source code for LaTeX documents.
+
+
+Customizing word diff
+^^^^^^^^^^^^^^^^^^^^^
+
+You can customize the rules that `git diff --color-words` uses to
+split words in a line, by specifying an appropriate regular expression
+in the "diff.*.wordRegex" configuration variable. For example, in TeX
+a backslash followed by a sequence of letters forms a command, but
+several such commands can be run together without intervening
+whitespace. To separate them, use a regular expression such as
+
+------------------------
+[diff "tex"]
+ wordRegex = "\\\\[a-zA-Z]+|[{}]|\\\\.|[^\\{}[:space:]]+"
+------------------------
+
+A built-in pattern is provided for all languages listed in the
+previous section.
+
+
+Performing text diffs of binary files
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Sometimes it is desirable to see the diff of a text-converted
+version of some binary files. For example, a word processor
+document can be converted to an ASCII text representation, and
+the diff of the text shown. Even though this conversion loses
+some information, the resulting diff is useful for human
+viewing (but cannot be applied directly).
+
+The `textconv` config option is used to define a program for
+performing such a conversion. The program should take a single
+argument, the name of a file to convert, and produce the
+resulting text on stdout.
+
+For example, to show the diff of the exif information of a
+file instead of the binary information (assuming you have the
+exif tool installed):
+
+------------------------
+[diff "jpg"]
+ textconv = exif
+------------------------
+
+NOTE: The text conversion is generally a one-way conversion;
+in this example, we lose the actual image contents and focus
+just on the text data. This means that diffs generated by
+textconv are _not_ suitable for applying. For this reason,
+only `git diff` and the `git log` family of commands (i.e.,
+log, whatchanged, show) will perform text conversion. `git
+format-patch` will never generate this output. If you want to
+send somebody a text-converted diff of a binary file (e.g.,
+because it quickly conveys the changes you have made), you
+should generate it separately and send it as a comment _in
+addition to_ the usual binary diff that you might send.
Performing a three-way merge
~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+`merge`
+^^^^^^^
+
The attribute `merge` affects how three versions of a file is
merged when a file-level merge is necessary during `git merge`,
and other programs such as `git revert` and `git cherry-pick`.
Set::
Built-in 3-way merge driver is used to merge the
- contents in a way similar to `merge` command of `RCS`
+ contents in a way similar to 'merge' command of `RCS`
suite. This is suitable for ordinary text files.
Unset::
^^^^^^^^^^^^
The `core.whitespace` configuration variable allows you to define what
-`diff` and `apply` should consider whitespace errors for all paths in
+'diff' and 'apply' should consider whitespace errors for all paths in
the project (See linkgit:git-config[1]). This attribute gives you finer
control per path.
variable.
+Creating an archive
+~~~~~~~~~~~~~~~~~~~
+
+`export-ignore`
+^^^^^^^^^^^^^^^
+
+Files and directories with the attribute `export-ignore` won't be added to
+archive files.
+
+`export-subst`
+^^^^^^^^^^^^^^
+
+If the attribute `export-subst` is set for a file then git will expand
+several placeholders when adding this file to an archive. The
+expansion depends on the availability of a commit ID, i.e., if
+linkgit:git-archive[1] has been given a tree instead of a commit or a
+tag then no replacement will be done. The placeholders are the same
+as those for the option `--pretty=format:` of linkgit:git-log[1],
+except that they need to be wrapped like this: `$Format:PLACEHOLDERS$`
+in the file. E.g. the string `$Format:%H$` will be replaced by the
+commit hash.
+
+
+Viewing files in GUI tools
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+`encoding`
+^^^^^^^^^^
+
+The value of this attribute specifies the character encoding that should
+be used by GUI tools (e.g. linkgit:gitk[1] and linkgit:git-gui[1]) to
+display the contents of the relevant file. Note that due to performance
+considerations linkgit:gitk[1] does not use this attribute unless you
+manually enable per-file encodings in its options.
+
+If this attribute is not set or has an invalid value, the value of the
+`gui.encoding` configuration variable is used instead
+(See linkgit:git-config[1]).
+
+
+USING ATTRIBUTE MACROS
+----------------------
+
+You do not want any end-of-line conversions applied to, nor textual diffs
+produced for, any binary file you track. You would need to specify e.g.
+
+------------
+*.jpg -crlf -diff
+------------
+
+but that may become cumbersome, when you have many attributes. Using
+attribute macros, you can specify groups of attributes set or unset at
+the same time. The system knows a built-in attribute macro, `binary`:
+
+------------
+*.jpg binary
+------------
+
+which is equivalent to the above. Note that the attribute macros can only
+be "Set" (see the above example that sets "binary" macro as if it were an
+ordinary attribute --- setting it in turn unsets "crlf" and "diff").
+
+
+DEFINING ATTRIBUTE MACROS
+-------------------------
+
+Custom attribute macros can be defined only in the `.gitattributes` file
+at the toplevel (i.e. not in any subdirectory). The built-in attribute
+macro "binary" is equivalent to:
+
+------------
+[attr]binary -diff -crlf
+------------
+
+
EXAMPLE
-------
----------------------------------------------------------------
-Creating an archive
-~~~~~~~~~~~~~~~~~~~
-
-`export-subst`
-^^^^^^^^^^^^^^
-
-If the attribute `export-subst` is set for a file then git will expand
-several placeholders when adding this file to an archive. The
-expansion depends on the availability of a commit ID, i.e. if
-linkgit:git-archive[1] has been given a tree instead of a commit or a
-tag then no replacement will be done. The placeholders are the same
-as those for the option `--pretty=format:` of linkgit:git-log[1],
-except that they need to be wrapped like this: `$Format:PLACEHOLDERS$`
-in the file. E.g. the string `$Format:%H$` will be replaced by the
-commit hash.
-
GIT
---
-Part of the linkgit:git[7] suite
+Part of the linkgit:git[1] suite