gitrepository-layout - Git Repository Layout




   A Git repository comes in two different flavours:

   *   a .git directory at the root of the working tree;

   *   a <project>.git directory that is a bare repository (i.e. without
       its own working tree), that is typically used for exchanging
       histories with others by pushing into it and fetching from it.

   Note: Also you can have a plain text file .git at the root of your
   working tree, containing gitdir: <path> to point at the real directory
   that has the repository. This mechanism is often used for a working
   tree of a submodule checkout, to allow you in the containing
   superproject to git checkout a branch that does not have the submodule.
   The checkout has to remove the entire submodule working tree, without
   losing the submodule repository.

   These things may exist in a Git repository.

       Object store associated with this repository. Usually an object
       store is self sufficient (i.e. all the objects that are referred to
       by an object found in it are also found in it), but there are a few
       ways to violate it.

        1. You could have an incomplete but locally usable repository by
           creating a shallow clone. See git-clone(1).

        2. You could be using the objects/info/alternates or
           $GIT_ALTERNATE_OBJECT_DIRECTORIES mechanisms to borrow objects
           from other object stores. A repository with this kind of
           incomplete object store is not suitable to be published for use
           with dumb transports but otherwise is OK as long as
           objects/info/alternates points at the object stores it borrows

           This directory is ignored if $GIT_COMMON_DIR is set and
           "$GIT_COMMON_DIR/objects" will be used instead.

       A newly created object is stored in its own file. The objects are
       splayed over 256 subdirectories using the first two characters of
       the sha1 object name to keep the number of directory entries in
       objects itself to a manageable number. Objects found here are often
       called unpacked (or loose) objects.

       Packs (files that store many object in compressed form, along with
       index files to allow them to be randomly accessed) are found in
       this directory.

       Additional information about the object store is recorded in this

       This file is to help dumb transports discover what packs are
       available in this object store. Whenever a pack is added or
       removed, git update-server-info should be run to keep this file
       up-to-date if the repository is published for dumb transports.  git
       repack does this by default.

       This file records paths to alternate object stores that this object
       store borrows objects from, one pathname per line. Note that not
       only native Git tools use it locally, but the HTTP fetcher also
       tries to use it remotely; this will usually work if you have
       relative paths (relative to the object database, not to the
       repository!) in your alternates file, but it will not work if you
       use absolute paths unless the absolute path in filesystem and web
       URL is the same. See also objects/info/http-alternates.

       This file records URLs to alternate object stores that this object
       store borrows objects from, to be used when the repository is
       fetched over HTTP.

       References are stored in subdirectories of this directory. The git
       prune command knows to preserve objects reachable from refs found
       in this directory and its subdirectories. This directory is ignored
       if $GIT_COMMON_DIR is set and "$GIT_COMMON_DIR/refs" will be used

       records tip-of-the-tree commit objects of branch name

       records any object name (not necessarily a commit object, or a tag
       object that points at a commit object).

       records tip-of-the-tree commit objects of branches copied from a
       remote repository.

       records the SHA-1 of the object that replaces <obj-sha1>. This is
       similar to info/grafts and is internally used and maintained by
       git-replace(1). Such refs can be exchanged between repositories
       while grafts are not.

       records the same information as refs/heads/, refs/tags/, and
       friends record in a more efficient way. See git-pack-refs(1). This
       file is ignored if $GIT_COMMON_DIR is set and
       "$GIT_COMMON_DIR/packed-refs" will be used instead.

       A symref (see glossary) to the refs/heads/ namespace describing the
       currently active branch. It does not mean much if the repository is
       not associated with any working tree (i.e. a bare repository), but
       a valid Git repository must have the HEAD file; some porcelains may
       use it to guess the designated "default" branch of the repository
       (usually master). It is legal if the named branch name does not
       (yet) exist. In some legacy setups, it is a symbolic link instead
       of a symref that points at the current branch.

       HEAD can also record a specific commit directly, instead of being a
       symref to point at the current branch. Such a state is often called
       detached HEAD.  See git-checkout(1) for details.

       Repository specific configuration file. This file is ignored if
       $GIT_COMMON_DIR is set and "$GIT_COMMON_DIR/config" will be used

       A slightly deprecated way to store shorthands to be used to specify
       a URL to git fetch, git pull and git push. A file can be stored as
       branches/<name> and then name can be given to these commands in
       place of repository argument. See the REMOTES section in git-
       fetch(1) for details. This mechanism is legacy and not likely to be
       found in modern repositories. This directory is ignored if
       $GIT_COMMON_DIR is set and "$GIT_COMMON_DIR/branches" will be used

       Hooks are customization scripts used by various Git commands. A
       handful of sample hooks are installed when git init is run, but all
       of them are disabled by default. To enable, the .sample suffix has
       to be removed from the filename by renaming. Read githooks(5) for
       more details about each hook. This directory is ignored if
       $GIT_COMMON_DIR is set and "$GIT_COMMON_DIR/hooks" will be used

       The current index file for the repository. It is usually not found
       in a bare repository.

       The shared index part, to be referenced by $GIT_DIR/index and other
       temporary index files. Only valid in split index mode.

       Additional information about the repository is recorded in this
       directory. This directory is ignored if $GIT_COMMON_DIR is set and
       "$GIT_COMMON_DIR/index" will be used instead.

       This file helps dumb transports discover what refs are available in
       this repository. If the repository is published for dumb
       transports, this file should be regenerated by git
       update-server-info every time a tag or branch is created or
       modified. This is normally done from the hooks/update hook, which
       is run by the git-receive-pack command when you git push into the

       This file records fake commit ancestry information, to pretend the
       set of parents a commit has is different from how the commit was
       actually created. One record per line describes a commit and its
       fake parents by listing their 40-byte hexadecimal object names
       separated by a space and terminated by a newline.

       Note that the grafts mechanism is outdated and can lead to problems
       transferring objects between repositories; see git-replace(1) for a
       more flexible and robust system to do the same thing.

       This file, by convention among Porcelains, stores the exclude
       pattern list.  .gitignore is the per-directory ignore file.  git
       status, git add, git rm and git clean look at it but the core Git
       commands do not look at it. See also: gitignore(5).

       This file stores sparse checkout patterns. See also: git-read-

       Stores shorthands for URL and default refnames for use when
       interacting with remote repositories via git fetch, git pull and
       git push commands. See the REMOTES section in git-fetch(1) for
       details. This mechanism is legacy and not likely to be found in
       modern repositories. This directory is ignored if $GIT_COMMON_DIR
       is set and "$GIT_COMMON_DIR/remotes" will be used instead.

       Records of changes made to refs are stored in this directory. See
       git-update-ref(1) for more information. This directory is ignored
       if $GIT_COMMON_DIR is set and "$GIT_COMMON_DIR/logs" will be used

       Records all changes made to the branch tip named name.

       Records all changes made to the tag named name.

       This is similar to info/grafts but is internally used and
       maintained by shallow clone mechanism. See --depth option to git-
       clone(1) and git-fetch(1). This file is ignored if $GIT_COMMON_DIR
       is set and "$GIT_COMMON_DIR/shallow" will be used instead.

       If this file exists, $GIT_COMMON_DIR (see git(1)) will be set to
       the path specified in this file if it is not explicitly set. If the
       specified path is relative, it is relative to $GIT_DIR. The
       repository with commondir is incomplete without the repository
       pointed by "commondir".

       Contains the git-repositories of the submodules.

       Contains administrative data for linked working trees. Each
       subdirectory contains the working tree-related part of a linked
       working tree. This directory is ignored if $GIT_COMMON_DIR is set,
       in which case "$GIT_COMMON_DIR/worktrees" will be used instead.

       A text file containing the absolute path back to the .git file that
       points to here. This is used to check if the linked repository has
       been manually removed and there is no need to keep this directory
       any more. The mtime of this file should be updated every time the
       linked repository is accessed.

       If this file exists, the linked working tree may be on a portable
       device and not available. The presence of this file prevents
       worktrees/<id> from being pruned either automatically or manually
       by git worktree prune. The file may contain a string explaining why
       the repository is locked.

       If this file exists, it is a hard link to the linked .git file. It
       is used to detect if the linked repository is manually removed.


   git-init(1), git-clone(1), git-fetch(1), git-pack-refs(1), git-gc(1),
   git-checkout(1), gitglossary(7), The Git User's Manual[1]


   Part of the git(1) suite.


    1. The Git User's Manual


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