A gitattributes file is a simple text file that gives attributes
to pathnames.
Each line in gitattributes file is of form:
pattern attr1 attr2 ...
That is, a pattern followed by an attributes list, separated by
whitespaces. Leading and trailing whitespaces are ignored. Lines
that begin with # are ignored. Patterns that begin with a double
quote are quoted in C style. When the pattern matches the path in
question, the attributes listed on the line are given to the
path.
Each attribute can be in one of these states for a given path:
Set
The path has the attribute with special value "true"; this is
specified by listing only the name of the attribute in the
attribute list.
Unset
The path has the attribute with special value "false"; this
is specified by listing the name of the attribute prefixed
with a dash - in the attribute list.
Set to a value
The path has the attribute with specified string value; this
is specified by listing the name of the attribute followed by
an equal sign = and its value in the attribute list.
Unspecified
No pattern matches the path, and nothing says if the path has
or does not have the attribute, the attribute for the path is
said to be Unspecified.
When more than one pattern matches the path, a later line
overrides an earlier line. This overriding is done per attribute.
The rules by which the pattern matches paths are the same as in
.gitignore files (see gitignore(5)), with a few exceptions:
• negative patterns are forbidden
• patterns that match a directory do not recursively match
paths inside that directory (so using the trailing-slash
path/ syntax is pointless in an attributes file; use path/**
instead)
When deciding what attributes are assigned to a path, Git
consults $GIT_DIR/info/attributes file (which has the highest
precedence), .gitattributes file in the same directory as the
path in question, and its parent directories up to the toplevel
of the work tree (the further the directory that contains
.gitattributes is from the path in question, the lower its
precedence). Finally global and system-wide files are considered
(they have the lowest precedence).
When the .gitattributes file is missing from the work tree, the
path in the index is used as a fall-back. During checkout
process, .gitattributes in the index is used and then the file in
the working tree is used as a fall-back.
If you wish to affect only a single repository (i.e., to assign
attributes to files that are particular to one user's workflow
for that repository), then attributes should be placed in the
$GIT_DIR/info/attributes file. Attributes which should be
version-controlled and distributed to other repositories (i.e.,
attributes of interest to all users) should go into
.gitattributes files. Attributes that should affect all
repositories for a single user should be placed in a file
specified by the core.attributesFile configuration option (see
git-config(1)). Its default value is
$XDG_CONFIG_HOME/git/attributes. If $XDG_CONFIG_HOME is either
not set or empty, $HOME/.config/git/attributes is used instead.
Attributes for all users on a system should be placed in the
$(prefix)/etc/gitattributes file.
Sometimes you would need to override a setting of an attribute
for a path to Unspecified state. This can be done by listing the
name of the attribute prefixed with an exclamation point !.
