Documentation / gitrepository-layout.txton commit setup.c: support multi-checkout repo setup (31e26eb)
   1gitrepository-layout(5)
   2=======================
   3
   4NAME
   5----
   6gitrepository-layout - Git Repository Layout
   7
   8SYNOPSIS
   9--------
  10$GIT_DIR/*
  11
  12DESCRIPTION
  13-----------
  14
  15A Git repository comes in two different flavours:
  16
  17 * a `.git` directory at the root of the working tree;
  18
  19 * a `<project>.git` directory that is a 'bare' repository
  20   (i.e. without its own working tree), that is typically used for
  21   exchanging histories with others by pushing into it and fetching
  22   from it.
  23
  24*Note*: Also you can have a plain text file `.git` at the root of
  25your working tree, containing `gitdir: <path>` to point at the real
  26directory that has the repository.  This mechanism is often used for
  27a working tree of a submodule checkout, to allow you in the
  28containing superproject to `git checkout` a branch that does not
  29have the submodule.  The `checkout` has to remove the entire
  30submodule working tree, without losing the submodule repository.
  31
  32These things may exist in a Git repository.
  33
  34objects::
  35        Object store associated with this repository.  Usually
  36        an object store is self sufficient (i.e. all the objects
  37        that are referred to by an object found in it are also
  38        found in it), but there are a few ways to violate it.
  39+
  40. You could have an incomplete but locally usable repository
  41by creating a shallow clone.  See linkgit:git-clone[1].
  42. You could be using the `objects/info/alternates` or
  43`$GIT_ALTERNATE_OBJECT_DIRECTORIES` mechanisms to 'borrow'
  44objects from other object stores.  A repository with this kind
  45of incomplete object store is not suitable to be published for
  46use with dumb transports but otherwise is OK as long as
  47`objects/info/alternates` points at the object stores it
  48borrows from.
  49+
  50This directory is ignored if $GIT_COMMON_DIR is set and
  51"$GIT_COMMON_DIR/objects" will be used instead.
  52
  53objects/[0-9a-f][0-9a-f]::
  54        A newly created object is stored in its own file.
  55        The objects are splayed over 256 subdirectories using
  56        the first two characters of the sha1 object name to
  57        keep the number of directory entries in `objects`
  58        itself to a manageable number. Objects found
  59        here are often called 'unpacked' (or 'loose') objects.
  60
  61objects/pack::
  62        Packs (files that store many object in compressed form,
  63        along with index files to allow them to be randomly
  64        accessed) are found in this directory.
  65
  66objects/info::
  67        Additional information about the object store is
  68        recorded in this directory.
  69
  70objects/info/packs::
  71        This file is to help dumb transports discover what packs
  72        are available in this object store.  Whenever a pack is
  73        added or removed, `git update-server-info` should be run
  74        to keep this file up-to-date if the repository is
  75        published for dumb transports.  'git repack' does this
  76        by default.
  77
  78objects/info/alternates::
  79        This file records paths to alternate object stores that
  80        this object store borrows objects from, one pathname per
  81        line. Note that not only native Git tools use it locally,
  82        but the HTTP fetcher also tries to use it remotely; this
  83        will usually work if you have relative paths (relative
  84        to the object database, not to the repository!) in your
  85        alternates file, but it will not work if you use absolute
  86        paths unless the absolute path in filesystem and web URL
  87        is the same. See also 'objects/info/http-alternates'.
  88
  89objects/info/http-alternates::
  90        This file records URLs to alternate object stores that
  91        this object store borrows objects from, to be used when
  92        the repository is fetched over HTTP.
  93
  94refs::
  95        References are stored in subdirectories of this
  96        directory.  The 'git prune' command knows to preserve
  97        objects reachable from refs found in this directory and
  98        its subdirectories. This directory is ignored if $GIT_COMMON_DIR
  99        is set and "$GIT_COMMON_DIR/refs" will be used instead.
 100
 101refs/heads/`name`::
 102        records tip-of-the-tree commit objects of branch `name`
 103
 104refs/tags/`name`::
 105        records any object name (not necessarily a commit
 106        object, or a tag object that points at a commit object).
 107
 108refs/remotes/`name`::
 109        records tip-of-the-tree commit objects of branches copied
 110        from a remote repository.
 111
 112refs/replace/`<obj-sha1>`::
 113        records the SHA-1 of the object that replaces `<obj-sha1>`.
 114        This is similar to info/grafts and is internally used and
 115        maintained by linkgit:git-replace[1]. Such refs can be exchanged
 116        between repositories while grafts are not.
 117
 118packed-refs::
 119        records the same information as refs/heads/, refs/tags/,
 120        and friends record in a more efficient way.  See
 121        linkgit:git-pack-refs[1]. This file is ignored if $GIT_COMMON_DIR
 122        is set and "$GIT_COMMON_DIR/packed-refs" will be used instead.
 123
 124HEAD::
 125        A symref (see glossary) to the `refs/heads/` namespace
 126        describing the currently active branch.  It does not mean
 127        much if the repository is not associated with any working tree
 128        (i.e. a 'bare' repository), but a valid Git repository
 129        *must* have the HEAD file; some porcelains may use it to
 130        guess the designated "default" branch of the repository
 131        (usually 'master').  It is legal if the named branch
 132        'name' does not (yet) exist.  In some legacy setups, it is
 133        a symbolic link instead of a symref that points at the current
 134        branch.
 135+
 136HEAD can also record a specific commit directly, instead of
 137being a symref to point at the current branch.  Such a state
 138is often called 'detached HEAD.'  See linkgit:git-checkout[1]
 139for details.
 140
 141config::
 142        Repository specific configuration file. This file is ignored
 143        if $GIT_COMMON_DIR is set and "$GIT_COMMON_DIR/config" will be
 144        used instead.
 145
 146branches::
 147        A slightly deprecated way to store shorthands to be used
 148        to specify a URL to 'git fetch', 'git pull' and 'git push'.
 149        A file can be stored as `branches/<name>` and then
 150        'name' can be given to these commands in place of
 151        'repository' argument.  See the REMOTES section in
 152        linkgit:git-fetch[1] for details.  This mechanism is legacy
 153        and not likely to be found in modern repositories. This
 154        directory is ignored if $GIT_COMMON_DIR is set and
 155        "$GIT_COMMON_DIR/branches" will be used instead.
 156
 157
 158hooks::
 159        Hooks are customization scripts used by various Git
 160        commands.  A handful of sample hooks are installed when
 161        'git init' is run, but all of them are disabled by
 162        default.  To enable, the `.sample` suffix has to be
 163        removed from the filename by renaming.
 164        Read linkgit:githooks[5] for more details about
 165        each hook. This directory is ignored if $GIT_COMMON_DIR is set
 166        and "$GIT_COMMON_DIR/hooks" will be used instead.
 167
 168
 169index::
 170        The current index file for the repository.  It is
 171        usually not found in a bare repository.
 172
 173sharedindex.<SHA-1>::
 174        The shared index part, to be referenced by $GIT_DIR/index and
 175        other temporary index files. Only valid in split index mode.
 176
 177info::
 178        Additional information about the repository is recorded
 179        in this directory. This directory is ignored if $GIT_COMMON_DIR
 180        is set and "$GIT_COMMON_DIR/index" will be used instead.
 181
 182info/refs::
 183        This file helps dumb transports discover what refs are
 184        available in this repository.  If the repository is
 185        published for dumb transports, this file should be
 186        regenerated by 'git update-server-info' every time a tag
 187        or branch is created or modified.  This is normally done
 188        from the `hooks/update` hook, which is run by the
 189        'git-receive-pack' command when you 'git push' into the
 190        repository.
 191
 192info/grafts::
 193        This file records fake commit ancestry information, to
 194        pretend the set of parents a commit has is different
 195        from how the commit was actually created.  One record
 196        per line describes a commit and its fake parents by
 197        listing their 40-byte hexadecimal object names separated
 198        by a space and terminated by a newline.
 199+
 200Note that the grafts mechanism is outdated and can lead to problems
 201transferring objects between repositories; see linkgit:git-replace[1]
 202for a more flexible and robust system to do the same thing.
 203
 204info/exclude::
 205        This file, by convention among Porcelains, stores the
 206        exclude pattern list. `.gitignore` is the per-directory
 207        ignore file.  'git status', 'git add', 'git rm' and
 208        'git clean' look at it but the core Git commands do not look
 209        at it.  See also: linkgit:gitignore[5].
 210
 211info/sparse-checkout::
 212        This file stores sparse checkout patterns.
 213        See also: linkgit:git-read-tree[1].
 214
 215remotes::
 216        Stores shorthands for URL and default refnames for use
 217        when interacting with remote repositories via 'git fetch',
 218        'git pull' and 'git push' commands.  See the REMOTES section
 219        in linkgit:git-fetch[1] for details.  This mechanism is legacy
 220        and not likely to be found in modern repositories. This
 221        directory is ignored if $GIT_COMMON_DIR is set and
 222        "$GIT_COMMON_DIR/remotes" will be used instead.
 223
 224logs::
 225        Records of changes made to refs are stored in this directory.
 226        See linkgit:git-update-ref[1] for more information. This
 227        directory is ignored if $GIT_COMMON_DIR is set and
 228        "$GIT_COMMON_DIR/logs" will be used instead.
 229
 230logs/refs/heads/`name`::
 231        Records all changes made to the branch tip named `name`.
 232
 233logs/refs/tags/`name`::
 234        Records all changes made to the tag named `name`.
 235
 236shallow::
 237        This is similar to `info/grafts` but is internally used
 238        and maintained by shallow clone mechanism.  See `--depth`
 239        option to linkgit:git-clone[1] and linkgit:git-fetch[1]. This
 240        file is ignored if $GIT_COMMON_DIR is set and
 241        "$GIT_COMMON_DIR/shallow" will be used instead.
 242
 243commondir::
 244        If this file exists, $GIT_COMMON_DIR (see linkgit:git[1]) will
 245        be set to the path specified in this file if it is not
 246        explicitly set. If the specified path is relative, it is
 247        relative to $GIT_DIR. The repository with commondir is
 248        incomplete without the repository pointed by "commondir".
 249
 250modules::
 251        Contains the git-repositories of the submodules. This
 252        directory is ignored if $GIT_COMMON_DIR is set and
 253        "$GIT_COMMON_DIR/modules" will be used instead.
 254
 255SEE ALSO
 256--------
 257linkgit:git-init[1],
 258linkgit:git-clone[1],
 259linkgit:git-fetch[1],
 260linkgit:git-pack-refs[1],
 261linkgit:git-gc[1],
 262linkgit:git-checkout[1],
 263linkgit:gitglossary[7],
 264link:user-manual.html[The Git User's Manual]
 265
 266GIT
 267---
 268Part of the linkgit:git[1] suite.