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       gitattributes - Defining attributes per path

       $GIT_DIR/info/attributes, .gitattributes

       A gitattributes file is a simple text file that gives attributes to

       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:

	   The path has the attribute with special value "true"; this is
	   specified by listing only the name of the attribute in the
	   attribute list.

	   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.

	   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:

       o   negative patterns are forbidden

       o   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 !.

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

   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 switch, 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.

	   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. Note that
	   setting core.autocrlf to true or input overrides core.eol (see the
	   definitions of those options in git-config(1)).

	       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.

	       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 conversion. If Git decides that the content is
	       text, its line endings are converted to LF on checkin. When the
	       file has been committed with CRLF, no conversion is done.

	       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

	   This attribute sets a specific line-ending style to be used in the
	   working directory. This attribute has effect only if the text
	   attribute is set or unspecified, or if it is set to auto, the file
	   is detected as text, and it is stored with LF endings in the index.
	   Note that setting this attribute on paths which are in the index
	   with CRLF line endings may make the paths to be considered dirty
	   unless text=auto is set. Adding the path to the index again will
	   normalize the line endings in the index.

	   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

	   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

	       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.

	   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 using any

		       autocrlf = true

	   This does not force normalization of 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 ensure that text files that any contributor
	   introduces to the repository have their line endings normalized,
	   you can set the text attribute to "auto" for all files.

	       *       text=auto

	   The attributes allow a fine-grained control, how the line endings
	   are converted. 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.

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

	       When text=auto conversion is enabled in a cross-platform
	       project using push and pull to a central repository the text
	       files containing CRLFs should be normalized.

	   From a clean working directory:

	       $ echo "* text=auto" >.gitattributes
	       $ git add --renormalize .
	       $ git status	   # Show files that will be normalized
	       $ 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...

	   o   git add itself does not touch the files in the work tree, the
	       next checkout would, so the safety triggers;

	   o   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;

	   o   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.

	   Git recognizes files encoded in ASCII or one of its supersets (e.g.
	   UTF-8, ISO-8859-1, ...) as text files. Files encoded in certain
	   other encodings (e.g. UTF-16) are interpreted as binary and
	   consequently built-in Git text processing tools (e.g. git diff) as
	   well as most Git web front ends do not visualize the contents of
	   these files by default.

	   In these cases you can tell Git the encoding of a file in the
	   working directory with the working-tree-encoding attribute. If a
	   file with this attribute is added to Git, then Git re-encodes the
	   content from the specified encoding to UTF-8. Finally, Git stores
	   the UTF-8 encoded content in its internal data structure (called
	   "the index"). On checkout the content is re-encoded back to the
	   specified encoding.

	   Please note that using the working-tree-encoding attribute may have
	   a number of pitfalls:

	   o   Alternative Git implementations (e.g. JGit or libgit2) and
	       older Git versions (as of March 2018) do not support the
	       working-tree-encoding attribute. If you decide to use the
	       working-tree-encoding attribute in your repository, then it is
	       strongly recommended to ensure that all clients working with
	       the repository support it.

	       For example, Microsoft Visual Studio resources files (*.rc) or
	       PowerShell script files (*.ps1) are sometimes encoded in
	       UTF-16. If you declare *.ps1 as files as UTF-16 and you add
	       foo.ps1 with a working-tree-encoding enabled Git client, then
	       foo.ps1 will be stored as UTF-8 internally. A client without
	       working-tree-encoding support will checkout foo.ps1 as UTF-8
	       encoded file. This will typically cause trouble for the users
	       of this file.

	       If a Git client that does not support the working-tree-encoding
	       attribute adds a new file bar.ps1, then bar.ps1 will be stored
	       "as-is" internally (in this example probably as UTF-16). A
	       client with working-tree-encoding support will interpret the
	       internal contents as UTF-8 and try to convert it to UTF-16 on
	       checkout. That operation will fail and cause an error.

	   o   Reencoding content to non-UTF encodings can cause errors as the
	       conversion might not be UTF-8 round trip safe. If you suspect
	       your encoding to not be round trip safe, then add it to
	       core.checkRoundtripEncoding to make Git check the round trip
	       encoding (see git-config(1)). SHIFT-JIS (Japanese character
	       set) is known to have round trip issues with UTF-8 and is
	       checked by default.

	   o   Reencoding content requires resources that might slow down
	       certain Git operations (e.g git checkout or git add).

	   Use the working-tree-encoding attribute only if you cannot store a
	   file in UTF-8 encoding and if you want Git to be able to process
	   the content as text.

	   As an example, use the following attributes if your *.ps1 files are
	   UTF-16 encoded with byte order mark (BOM) and you want Git to
	   perform automatic line ending conversion based on your platform.

	       *.ps1	       text working-tree-encoding=UTF-16

	   Use the following attributes if your *.ps1 files are UTF-16 little
	   endian encoded without BOM and you want Git to use Windows line
	   endings in the working directory (use UTF-16LE-BOM instead of
	   UTF-16LE if you want UTF-16 little endian with BOM). Please note,
	   it is highly recommended to explicitly define the line endings with
	   eol if the working-tree-encoding attribute is used to avoid

	       *.ps1	       text working-tree-encoding=UTF-16LE eol=CRLF

	   You can get a list of all available encodings on your platform with
	   the following command:

	       iconv --list

	   If you do not know the encoding of a file, then you can use the
	   file command to guess the encoding:

	       file foo.ps1

	   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.

	   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. By default these
	   commands process only a single blob and terminate. If a long
	   running process filter is used in place of clean and/or smudge
	   filters, then Git can process all blobs with a single filter
	   command invocation for the entire life of a single Git command, for
	   example git add --all. If a long running process filter is
	   configured then it always takes precedence over a configured single
	   blob filter. See section below for the description of the protocol
	   used to communicate with a process filter.

	   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.

	   Note: Whenever the clean filter is changed, the repo should be
	   renormalized: $ git add --renormalize .

	   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

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

	   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

	   Note that "%f" is the name of the path that is being worked on.
	   Depending on the version that is being filtered, the corresponding
	   file on disk may not exist, or may have different contents. So,
	   smudge and clean commands should not try to access the file on
	   disk, but only act as filters on the content provided to them on
	   standard input.

       Long Running Filter Process
	   If the filter command (a string value) is defined via
	   filter.<driver>.process then Git can process all blobs with a
	   single filter invocation for the entire life of a single Git
	   command. This is achieved by using the long-running process
	   protocol (described in

	   When Git encounters the first file that needs to be cleaned or
	   smudged, it starts the filter and performs the handshake. In the
	   handshake, the welcome message sent by Git is "git-filter-client",
	   only version 2 is supported, and the supported capabilities are
	   "clean", "smudge", and "delay".

	   Afterwards Git sends a list of "key=value" pairs terminated with a
	   flush packet. The list will contain at least the filter command
	   (based on the supported capabilities) and the pathname of the file
	   to filter relative to the repository root. Right after the flush
	   packet Git sends the content split in zero or more pkt-line packets
	   and a flush packet to terminate content. Please note, that the
	   filter must not send any response before it received the content
	   and the final flush packet. Also note that the "value" of a
	   "key=value" pair can contain the "=" character whereas the key
	   would never contain that character.

	       packet:		git> command=smudge
	       packet:		git> pathname=path/testfile.dat
	       packet:		git> 0000
	       packet:		git> CONTENT
	       packet:		git> 0000

	   The filter is expected to respond with a list of "key=value" pairs
	   terminated with a flush packet. If the filter does not experience
	   problems then the list must contain a "success" status. Right after
	   these packets the filter is expected to send the content in zero or
	   more pkt-line packets and a flush packet at the end. Finally, a
	   second list of "key=value" pairs terminated with a flush packet is
	   expected. The filter can change the status in the second list or
	   keep the status as is with an empty list. Please note that the
	   empty list must be terminated with a flush packet regardless.

	       packet:		git< status=success
	       packet:		git< 0000
	       packet:		git< SMUDGED_CONTENT
	       packet:		git< 0000
	       packet:		git< 0000  # empty list, keep "status=success" unchanged!

	   If the result content is empty then the filter is expected to
	   respond with a "success" status and a flush packet to signal the
	   empty content.

	       packet:		git< status=success
	       packet:		git< 0000
	       packet:		git< 0000  # empty content!
	       packet:		git< 0000  # empty list, keep "status=success" unchanged!

	   In case the filter cannot or does not want to process the content,
	   it is expected to respond with an "error" status.

	       packet:		git< status=error
	       packet:		git< 0000

	   If the filter experiences an error during processing, then it can
	   send the status "error" after the content was (partially or
	   completely) sent.

	       packet:		git< status=success
	       packet:		git< 0000
	       packet:		git< 0000
	       packet:		git< status=error
	       packet:		git< 0000

	   In case the filter cannot or does not want to process the content
	   as well as any future content for the lifetime of the Git process,
	   then it is expected to respond with an "abort" status at any point
	   in the protocol.

	       packet:		git< status=abort
	       packet:		git< 0000

	   Git neither stops nor restarts the filter process in case the
	   "error"/"abort" status is set. However, Git sets its exit code
	   according to the filter.<driver>.required flag, mimicking the
	   behavior of the filter.<driver>.clean / filter.<driver>.smudge

	   If the filter dies during the communication or does not adhere to
	   the protocol then Git will stop the filter process and restart it
	   with the next file that needs to be processed. Depending on the
	   filter.<driver>.required flag Git will interpret that as error.

	   If the filter supports the "delay" capability, then Git can send
	   the flag "can-delay" after the filter command and pathname. This
	   flag denotes that the filter can delay filtering the current blob
	   (e.g. to compensate network latencies) by responding with no
	   content but with the status "delayed" and a flush packet.

	       packet:		git> command=smudge
	       packet:		git> pathname=path/testfile.dat
	       packet:		git> can-delay=1
	       packet:		git> 0000
	       packet:		git> CONTENT
	       packet:		git> 0000
	       packet:		git< status=delayed
	       packet:		git< 0000

	   If the filter supports the "delay" capability then it must support
	   the "list_available_blobs" command. If Git sends this command, then
	   the filter is expected to return a list of pathnames representing
	   blobs that have been delayed earlier and are now available. The
	   list must be terminated with a flush packet followed by a "success"
	   status that is also terminated with a flush packet. If no blobs for
	   the delayed paths are available, yet, then the filter is expected
	   to block the response until at least one blob becomes available.
	   The filter can tell Git that it has no more delayed blobs by
	   sending an empty list. As soon as the filter responds with an empty
	   list, Git stops asking. All blobs that Git has not received at this
	   point are considered missing and will result in an error.

	       packet:		git> command=list_available_blobs
	       packet:		git> 0000
	       packet:		git< pathname=path/testfile.dat
	       packet:		git< pathname=path/otherfile.dat
	       packet:		git< 0000
	       packet:		git< status=success
	       packet:		git< 0000

	   After Git received the pathnames, it will request the corresponding
	   blobs again. These requests contain a pathname and an empty content
	   section. The filter is expected to respond with the smudged content
	   in the usual way as explained above.

	       packet:		git> command=smudge
	       packet:		git> pathname=path/testfile.dat
	       packet:		git> 0000
	       packet:		git> 0000  # empty content!
	       packet:		git< status=success
	       packet:		git< 0000
	       packet:		git< SMUDGED_CONTENT
	       packet:		git< 0000
	       packet:		git< 0000  # empty list, keep "status=success" unchanged!

	   A long running filter demo implementation can be found in
	   contrib/long-running-filter/example.pl located in the Git core
	   repository. If you develop your own long running filter process
	   then the GIT_TRACE_PACKET environment variables can be very helpful
	   for debugging (see git(1)).

	   Please note that you cannot use an existing filter.<driver>.clean
	   or filter.<driver>.smudge command with filter.<driver>.process
	   because the former two use a different inter process communication
	   protocol than the latter one.

       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

	   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
	   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.

	       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.

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

	       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.

	       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

	       *.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:

	   o   ada suitable for source code in the Ada language.

	   o   bash suitable for source code in the Bourne-Again SHell
	       language. Covers a superset of POSIX shell function

	   o   bibtex suitable for files with BibTeX coded references.

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

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

	   o   css suitable for cascading style sheets.

	   o   dts suitable for devicetree (DTS) files.

	   o   elixir suitable for source code in the Elixir language.

	   o   fortran suitable for source code in the Fortran language.

	   o   fountain suitable for Fountain documents.

	   o   golang suitable for source code in the Go language.

	   o   html suitable for HTML/XHTML documents.

	   o   java suitable for source code in the Java language.

	   o   kotlin suitable for source code in the Kotlin language.

	   o   markdown suitable for Markdown documents.

	   o   matlab suitable for source code in the MATLAB and Octave

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

	   o   pascal suitable for source code in the Pascal/Delphi language.

	   o   perl suitable for source code in the Perl language.

	   o   php suitable for source code in the PHP language.

	   o   python suitable for source code in the Python language.

	   o   ruby suitable for source code in the Ruby language.

	   o   rust suitable for source code in the Rust language.

	   o   scheme suitable for source code in the Scheme language.

	   o   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

	       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

	    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

	       [diff "ps"]
		 textconv = ps2ascii
		 binary = true

   Performing a three-way 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.

	       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.

	       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

	       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

	       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.

	       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.

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

	       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

	   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.

	   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
	   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.

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

	       Do not notice anything as error.

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

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

   Creating an archive
	   Files and directories with the attribute export-ignore won't be
	   added to archive files.

	   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. However, only one %(describe) placeholder is expanded per
	   archive to avoid denial-of-service attacks.

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

   Viewing files in GUI tools
	   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-

       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"

       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

       Git does not follow symbolic links when accessing a .gitattributes file
       in the working tree. This keeps behavior consistent when the file is
       accessed from the index or a tree versus from the filesystem.

       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


       Part of the git(1) suite

Git 2.38.4			  05/16/2024		      GITATTRIBUTES(5)