NAME

       gitrepository-layout - Git Repository Layout

SYNOPSIS

       $GIT_DIR/*

DESCRIPTION

       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.

       objects
           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 from.

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

       objects/[0-9a-f][0-9a-f]
           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.

       objects/pack
           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.

       objects/info
           Additional information about the object store is recorded in this directory.

       objects/info/packs
           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.

       objects/info/alternates
           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.

       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.

       refs
           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 instead.

       refs/heads/name
           records tip-of-the-tree commit objects of branch name

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

       refs/remotes/name
           records tip-of-the-tree commit objects of branches copied from a remote repository.

       refs/replace/<obj-sha1>
           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.

       packed-refs
           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.

       HEAD
           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.

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

       branches
           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 instead.

       hooks
           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 instead.

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

       sharedindex.<SHA-1>
           The shared index part, to be referenced by $GIT_DIR/index and other temporary index files. Only valid
           in split index mode.

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

       info/refs
           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
           repository.

       info/grafts
           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.

       info/exclude
           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).

       info/attributes
           Defines which attributes to assign to a path, similar to per-directory .gitattributes files. See
           also: gitattributes(5).

       info/sparse-checkout
           This file stores sparse checkout patterns. See also: git-read-tree(1).

       remotes
           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.

       logs
           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 instead.

       logs/refs/heads/name
           Records all changes made to the branch tip named name.

       logs/refs/tags/name
           Records all changes made to the tag named name.

       shallow
           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.

       commondir
           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".

       modules
           Contains the git-repositories of the submodules.

       worktrees
           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.

       worktrees/<id>/gitdir
           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.

       worktrees/<id>/locked
           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.

       worktrees/<id>/link
           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.

SEE ALSO

       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]

GIT

       Part of the git(1) suite

NOTES

        1. The Git User’s Manual
           file:///usr/share/doc/git/html/user-manual.html