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NAME

       gitattributes - defining attributes per path

SYNOPSIS

       $GIT_DIR/info/attributes, .gitattributes

DESCRIPTION

       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. 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 how the pattern matches paths are the same as
       in .gitignore files; see gitignore(5). Unlike .gitignore, negative patterns are forbidden.

       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 an 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 !.

EFFECTS

       Certain operations by Git can be influenced by assigning particular attributes to a path.
       Currently, the following operations are attributes-aware.

   Checking-out and checking-in
       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 Git stores the contents you prepare in the working tree in the repository upon git add
       and git commit.

       text
           This attribute enables and controls end-of-line normalization. When a text file is
           normalized, its line endings are converted to LF in the repository. To control what
           line ending style is used in the working directory, use the eol attribute for a single
           file and the core.eol configuration variable for all text files.

           Set
               Setting the text attribute on a path enables end-of-line normalization and marks
               the path as a text file. End-of-line conversion takes place without guessing the
               content type.

           Unset
               Unsetting the text attribute on a path tells Git not to attempt any end-of-line
               conversion upon checkin or checkout.

           Set to string value "auto"
               When text is set to "auto", the path is marked for automatic end-of-line
               normalization. If Git decides that the content is text, its line endings are
               normalized to LF on checkin.

           Unspecified
               If the text attribute is unspecified, Git uses the core.autocrlf configuration
               variable to determine if the file should be converted.

           Any other value causes Git to act as if text has been left unspecified.

       eol
           This attribute sets a specific line-ending style to be used in the working directory.
           It enables end-of-line normalization without any content checks, effectively setting
           the text attribute.

           Set to string value "crlf"
               This setting forces Git to normalize line endings for this file on checkin and
               convert them to CRLF when the file is checked out.

           Set to string value "lf"
               This setting forces Git to normalize line endings to LF on checkin and prevents
               conversion to CRLF when the file is checked out.

       Backwards compatibility with crlf attribute
           For backwards compatibility, the crlf attribute is interpreted as follows:

               crlf            text
               -crlf           -text
               crlf=input      eol=lf

       End-of-line conversion
           While Git normally leaves file contents alone, it can be configured to normalize line
           endings to LF in the repository and, optionally, to convert them to CRLF when files
           are checked out.

           Here is an example that will make Git normalize .txt, .vcproj and .sh files, ensure
           that .vcproj files have CRLF and .sh files have LF in the working directory, and
           prevent .jpg files from being normalized regardless of their content.

               *.txt           text
               *.vcproj        eol=crlf
               *.sh            eol=lf
               *.jpg           -text

           Other source code management systems normalize all text files in their repositories,
           and there are two ways to enable similar automatic normalization in Git.

           If you simply want to have CRLF line endings in your working directory regardless of
           the repository you are working with, you can set the config variable "core.autocrlf"
           without changing any attributes.

               [core]
                       autocrlf = true

           This does not force normalization of all text files, but does ensure that text files
           that you introduce to the repository have their line endings normalized to LF when
           they are added, and that files that are already normalized in the repository stay
           normalized.

           If you want to interoperate with a source code management system that enforces
           end-of-line normalization, or you simply want all text files in your repository to be
           normalized, you should instead set the text attribute to "auto" for all files.

               *       text=auto

           This ensures that all files that Git considers to be text will have normalized (LF)
           line endings in the repository. The core.eol configuration variable controls which
           line endings Git will use for normalized files in your working directory; the default
           is to use the native line ending for your platform, or CRLF if core.autocrlf is set.

               Note
               When text=auto normalization is enabled in an existing repository, any text files
               containing CRLFs should be normalized. If they are not they will be normalized the
               next time someone tries to change them, causing unfortunate misattribution. From a
               clean working directory:

               $ echo "* text=auto" >>.gitattributes
               $ rm .git/index     # Remove the index to force Git to
               $ git reset         # re-scan the working directory
               $ git status        # Show files that will be normalized
               $ git add -u
               $ git add .gitattributes
               $ git commit -m "Introduce end-of-line normalization"

           If any files that should not be normalized show up in git status, unset their text
           attribute before running git add -u.

               manual.pdf      -text

           Conversely, text files that Git does not detect can have normalization enabled
           manually.

               weirdchars.txt  text

           If core.safecrlf is set to "true" or "warn", Git verifies if the conversion is
           reversible for the current setting of core.autocrlf. For "true", Git rejects
           irreversible conversions; for "warn", Git only prints a warning but accepts an
           irreversible conversion. The safety triggers to prevent such 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 next checkout would,
               so the safety triggers;

           ·   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 catch potential problems early,
               safety triggers.

       ident
           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 with $Id$ upon check-in.

       filter
           A filter attribute can be set to a string value that names a filter driver specified
           in the configuration.

           A filter driver consists of a clean command and a smudge command, either of which can
           be left unspecified. Upon checkout, when the smudge command is specified, the command
           is fed the blob object from its standard input, and its standard output is used to
           update the worktree file. Similarly, the clean command is used to convert the contents
           of worktree file upon checkin.

           One use of the content filtering is to massage the content into a shape that is more
           convenient for the platform, filesystem, and the user to use. For this mode of
           operation, the key phrase here is "more convenient" and not "turning something
           unusable into usable". In other words, the intent is that if someone unsets the filter
           driver definition, or does not have the appropriate filter program, the project should
           still be usable.

           Another use of the content filtering is to store the content that cannot be directly
           used in the repository (e.g. a UUID that refers to the true content stored outside
           Git, or an encrypted content) and turn it into a usable form upon checkout (e.g.
           download the external content, or decrypt the encrypted content).

           These two filters behave differently, and by default, a filter is taken as the former,
           massaging the contents into more convenient shape. A missing filter driver definition
           in the config, or a filter driver that exits with a non-zero status, is not an error
           but makes the filter a no-op passthru.

           You can declare that a filter turns a content that by itself is unusable into a usable
           content by setting the filter.<driver>.required configuration variable to true.

           For example, in .gitattributes, you would assign the filter attribute for paths.

               *.c     filter=indent

           Then you would define a "filter.indent.clean" and "filter.indent.smudge" configuration
           in your .git/config to specify a pair of commands to modify the contents of C programs
           when the source files are checked in ("clean" is run) and checked out (no change is
           made because the command is "cat").

               [filter "indent"]
                       clean = indent
                       smudge = cat

           For best results, clean should not alter its output further if it is run twice
           ("clean→clean" should be equivalent to "clean"), and multiple smudge commands should
           not alter clean's output ("smudge→smudge→clean" should be equivalent to "clean"). See
           the section on merging below.

           The "indent" filter is well-behaved in this regard: it will not modify input that is
           already correctly indented. In this case, the lack of a smudge filter means that the
           clean filter must accept its own output without modifying it.

           If a filter must succeed in order to make the stored contents usable, you can declare
           that the filter is required, in the configuration:

               [filter "crypt"]
                       clean = openssl enc ...
                       smudge = openssl enc -d ...
                       required

           Sequence "%f" on the filter command line is replaced with the name of the file the
           filter is working on. A filter might use this in keyword substitution. For example:

               [filter "p4"]
                       clean = git-p4-filter --clean %f
                       smudge = git-p4-filter --smudge %f

       Interaction between checkin/checkout attributes
           In the check-in codepath, the worktree file is first converted with filter driver (if
           specified and corresponding driver defined), then the result is processed with ident
           (if specified), and then finally with text (again, if specified and applicable).

           In the check-out codepath, the blob content is first converted with text, and then
           ident and fed to filter.

       Merging branches with differing checkin/checkout attributes
           If you have added attributes to a file that cause the canonical repository format for
           that file to change, such as adding a clean/smudge filter or text/eol/ident
           attributes, merging anything where the attribute is not in place would normally cause
           merge conflicts.

           To prevent these unnecessary merge conflicts, Git can be told to run a virtual
           check-out and check-in of all three stages of a file when resolving a three-way merge
           by setting the merge.renormalize configuration variable. This prevents changes caused
           by check-in conversion from causing spurious merge conflicts when a converted file is
           merged with an unconverted file.

           As long as a "smudge→clean" results in the same output as a "clean" even on files that
           are already smudged, this strategy will automatically resolve all filter-related
           conflicts. Filters that do not act in this way may cause additional merge conflicts
           that must be resolved manually.

   Generating diff text
       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
               A path to which the diff attribute is set is treated as text, even when they
               contain byte values that normally never appear in text files, such as NUL.

           Unset
               A path to which the diff attribute is unset will generate Binary files differ (or
               a binary patch, if binary patches are enabled).

           Unspecified
               A path to which the diff attribute is unspecified first gets its contents
               inspected, and if it looks like text and is smaller than core.bigFileThreshold, it
               is treated as text. Otherwise it would generate Binary files differ.

           String
               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 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 an external diff driver jcdiff, add a section to your $GIT_DIR/config file
           (or $HOME/.gitconfig file) like this:

               [diff "jcdiff"]
                       command = j-c-diff

           When Git needs to show you a diff for the path with diff 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 git(1) for details.

       Defining a custom hunk-header
           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

           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 for paths.

               *.tex   diff=tex

           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
           "TEXT". Add a section to your $GIT_DIR/config file (or $HOME/.gitconfig file) like
           this:

               [diff "tex"]
                       xfuncname = "^(\\\\(sub)*section\\{.*)$"

           Note. A single level of backslashes are eaten by the configuration file parser, so you
           would need to double the backslashes; the pattern above picks a line that begins with
           a backslash, and zero or more occurrences of sub followed by section followed by open
           brace, to the end of line.

           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). The following built in
           patterns are available:

           ·   ada suitable for source code in the Ada language.

           ·   bibtex suitable for files with BibTeX coded references.

           ·   cpp suitable for source code in the C and C++ languages.

           ·   csharp suitable for source code in the C# language.

           ·   fortran suitable for source code in the Fortran language.

           ·   fountain suitable for Fountain documents.

           ·   html suitable for HTML/XHTML documents.

           ·   java suitable for source code in the Java language.

           ·   matlab suitable for source code in the MATLAB language.

           ·   objc suitable for source code in the Objective-C language.

           ·   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.

           ·   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 --word-diff 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 in your
           $GIT_DIR/config file (or $HOME/.gitconfig file) like this:

               [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), add the following section to
           your $GIT_DIR/config file (or $HOME/.gitconfig file):

               [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.

           Because text conversion can be slow, especially when doing a large number of them with
           git log -p, Git provides a mechanism to cache the output and use it in future diffs.
           To enable caching, set the "cachetextconv" variable in your diff driver’s config. For
           example:

               [diff "jpg"]
                       textconv = exif
                       cachetextconv = true

           This will cache the result of running "exif" on each blob indefinitely. If you change
           the textconv config variable for a diff driver, Git will automatically invalidate the
           cache entries and re-run the textconv filter. If you want to invalidate the cache
           manually (e.g., because your version of "exif" was updated and now produces better
           output), you can remove the cache 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 are merged when a file-level
           merge is necessary during git merge, and other commands 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 suite. This is suitable for ordinary text files.

           Unset
               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 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 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
               3-way merge is performed using the specified custom merge driver. The built-in
               3-way merge driver can be explicitly specified by asking for "text" driver; the
               built-in "take the current branch" driver can be requested with "binary".

       Built-in merge drivers
           There are a few built-in low-level merge drivers defined that can be asked for via the
           merge attribute.

           text
               Usual 3-way file level merge for text files. Conflicted regions are marked with
               conflict markers <<<<<<<, ======= and >>>>>>>. The version from your branch
               appears before the ======= marker, and the version from the merged branch appears
               after the ======= marker.

           binary
               Keep the version from your branch in the work tree, but leave the path in the
               conflicted state for the user to sort out.

           union
               Run 3-way file level merge for text files, but take lines from both versions,
               instead of leaving conflict markers. This tends to leave the added lines in the
               resulting file in random order and the user should verify the result. Do not use
               this if you do not understand the implications.

       Defining a custom merge driver
           The definition of a merge driver is done in the .git/config file, not in the
           gitattributes file, so strictly speaking this manual page is a wrong place to talk
           about it. However...

           To define a custom merge driver filfre, add a section to your $GIT_DIR/config file (or
           $HOME/.gitconfig file) like this:

               [merge "filfre"]
                       name = feel-free merge driver
                       driver = filfre %O %A %B %L %P
                       recursive = binary

           The merge.*.name variable gives the driver a human-readable name.

           The ‘merge.*.driver` variable’s value is used to construct a command to run to merge
           ancestor’s version (%O), current version (%A) and the other branches’ version (%B).
           These three tokens are replaced with the names of temporary files that hold the
           contents of these versions when the command line is built. Additionally, %L will be
           replaced with the conflict marker size (see below).

           The merge driver is expected to leave the result of the merge in the file named with
           %A by overwriting it, and exit with zero status if it managed to merge them cleanly,
           or non-zero if there were conflicts.

           The merge.*.recursive variable specifies what other merge driver to use when the merge
           driver is called for an internal merge between common ancestors, when there are more
           than one. When left unspecified, the driver itself is used for both internal merge and
           the final merge.

           The merge driver can learn the pathname in which the merged result will be stored via
           placeholder %P.

       conflict-marker-size
           This attribute controls the length of conflict markers left in the work tree file
           during a conflicted merge. Only setting to the value to a positive integer has any
           meaningful effect.

           For example, this line in .gitattributes can be used to tell the merge machinery to
           leave much longer (instead of the usual 7-character-long) conflict markers when
           merging the file Documentation/git-merge.txt results in a conflict.

               Documentation/git-merge.txt     conflict-marker-size=32

   Checking whitespace errors
       whitespace
           The core.whitespace configuration variable allows you to define what diff and apply
           should consider whitespace errors for all paths in the project (See git-config(1)).
           This attribute gives you finer control per path.

           Set
               Notice all types of potential whitespace errors known to Git. The tab width is
               taken from the value of the core.whitespace configuration variable.

           Unset
               Do not notice anything as error.

           Unspecified
               Use the value of the core.whitespace configuration variable to decide what to
               notice as error.

           String
               Specify a comma separate list of common whitespace problems to notice in the same
               format as the core.whitespace configuration 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 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 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.

   Packing objects
       delta
           Delta compression will not be attempted for blobs for paths with the attribute delta
           set to false.

   Viewing files in GUI tools
       encoding
           The value of this attribute specifies the character encoding that should be used by
           GUI tools (e.g. gitk(1) and git-gui(1)) to display the contents of the relevant file.
           Note that due to performance considerations 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 git-config(1)).

USING MACRO ATTRIBUTES

       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 -text -diff

       but that may become cumbersome, when you have many attributes. Using macro attributes, you
       can define an attribute that, when set, also sets or unsets a number of other attributes
       at the same time. The system knows a built-in macro attribute, binary:

           *.jpg binary

       Setting the "binary" attribute also unsets the "text" and "diff" attributes as above. Note
       that macro attributes can only be "Set", though setting one might have the effect of
       setting or unsetting other attributes or even returning other attributes to the
       "Unspecified" state.

DEFINING MACRO ATTRIBUTES

       Custom macro attributes can be defined only in top-level gitattributes files
       ($GIT_DIR/info/attributes, the .gitattributes file at the top level of the working tree,
       or the global or system-wide gitattributes files), not in .gitattributes files in working
       tree subdirectories. The built-in macro attribute "binary" is equivalent to:

           [attr]binary -diff -merge -text

EXAMPLE

       If you have these three gitattributes file:

           (in $GIT_DIR/info/attributes)

           a*      foo !bar -baz

           (in .gitattributes)
           abc     foo bar baz

           (in t/.gitattributes)
           ab*     merge=filfre
           abc     -foo -bar
           *.c     frotz

       the attributes given to path t/abc are computed as follows:

        1. By examining t/.gitattributes (which is in the same directory as the path in
           question), Git finds that the first line matches.  merge attribute is set. It also
           finds that the second line matches, and attributes foo and bar are unset.

        2. Then it examines .gitattributes (which is in the parent directory), and finds that the
           first line matches, but t/.gitattributes file already decided how merge, foo and bar
           attributes should be given to this path, so it leaves foo and bar unset. Attribute baz
           is set.

        3. Finally it examines $GIT_DIR/info/attributes. This file is used to override the
           in-tree settings. The first line is a match, and foo is set, bar is reverted to
           unspecified state, and baz is unset.

       As the result, the attributes assignment to t/abc becomes:

           foo     set to true
           bar     unspecified
           baz     set to false
           merge   set to string value "filfre"
           frotz   unspecified

SEE ALSO

       git-check-attr(1).

GIT

       Part of the git(1) suite