Documentation/git-submodule.txt

   1 git-submodule(1)
   2 ================
   3
   4 NAME
   5 ----
   6 git-submodule - Initialize, update or inspect submodules
   7
   8
   9 SYNOPSIS
  10 --------
  11 [verse]
  12 'git submodule' [--quiet] add [-b branch]
  13               [--reference <repository>] [--] <repository> <path>
  14 'git submodule' [--quiet] status [--cached] [--] [<path>...]
  15 'git submodule' [--quiet] init [--] [<path>...]
  16 'git submodule' [--quiet] update [--init] [-N|--no-fetch] [--rebase]
  17               [--reference <repository>] [--] [<path>...]
  18 'git submodule' [--quiet] summary [--summary-limit <n>] [commit] [--] [<path>...]
  19 'git submodule' [--quiet] foreach <command>
  20 'git submodule' [--quiet] sync [--] [<path>...]
  21
  22
  23 DESCRIPTION
  24 -----------
  25 Submodules allow foreign repositories to be embedded within
  26 a dedicated subdirectory of the source tree, always pointed
  27 at a particular commit.
  28
  29 They are not to be confused with remotes, which are meant mainly
  30 for branches of the same project; submodules are meant for
  31 different projects you would like to make part of your source tree,
  32 while the history of the two projects still stays completely
  33 independent and you cannot modify the contents of the submodule
  34 from within the main project.
  35 If you want to merge the project histories and want to treat the
  36 aggregated whole as a single project from then on, you may want to
  37 add a remote for the other project and use the 'subtree' merge strategy,
  38 instead of treating the other project as a submodule. Directories
  39 that come from both projects can be cloned and checked out as a whole
  40 if you choose to go that route.
  41
  42 Submodules are composed from a so-called `gitlink` tree entry
  43 in the main repository that refers to a particular commit object
  44 within the inner repository that is completely separate.
  45 A record in the `.gitmodules` file at the root of the source
  46 tree assigns a logical name to the submodule and describes
  47 the default URL the submodule shall be cloned from.
  48 The logical name can be used for overriding this URL within your
  49 local repository configuration (see 'submodule init').
  50
  51 This command will manage the tree entries and contents of the
  52 gitmodules file for you, as well as inspect the status of your
  53 submodules and update them.
  54 When adding a new submodule to the tree, the 'add' subcommand
  55 is to be used.  However, when pulling a tree containing submodules,
  56 these will not be checked out by default;
  57 the 'init' and 'update' subcommands will maintain submodules
  58 checked out and at appropriate revision in your working tree.
  59 You can briefly inspect the up-to-date status of your submodules
  60 using the 'status' subcommand and get a detailed overview of the
  61 difference between the index and checkouts using the 'summary'
  62 subcommand.
  63
  64
  65 COMMANDS
  66 --------
  67 add::
  68         Add the given repository as a submodule at the given path
  69         to the changeset to be committed next to the current
  70         project: the current project is termed the "superproject".
  71 +
  72 This requires two arguments: <repository> and <path>.
  73 +
  74 <repository> is the URL of the new submodule's origin repository.
  75 This may be either an absolute URL, or (if it begins with ./
  76 or ../), the location relative to the superproject's origin
  77 repository.
  78 +
  79 <path> is the relative location for the cloned submodule to
  80 exist in the superproject. If <path> does not exist, then the
  81 submodule is created by cloning from the named URL. If <path> does
  82 exist and is already a valid git repository, then this is added
  83 to the changeset without cloning. This second form is provided
  84 to ease creating a new submodule from scratch, and presumes
  85 the user will later push the submodule to the given URL.
  86 +
  87 In either case, the given URL is recorded into .gitmodules for
  88 use by subsequent users cloning the superproject. If the URL is
  89 given relative to the superproject's repository, the presumption
  90 is the superproject and submodule repositories will be kept
  91 together in the same relative location, and only the
  92 superproject's URL needs to be provided: git-submodule will correctly
  93 locate the submodule using the relative URL in .gitmodules.
  94
  95 status::
  96         Show the status of the submodules. This will print the SHA-1 of the
  97         currently checked out commit for each submodule, along with the
  98         submodule path and the output of 'git-describe' for the
  99         SHA-1. Each SHA-1 will be prefixed with `-` if the submodule is not
 100         initialized and `+` if the currently checked out submodule commit
 101         does not match the SHA-1 found in the index of the containing
 102         repository. This command is the default command for 'git-submodule'.
 103
 104 init::
 105         Initialize the submodules, i.e. register each submodule name
 106         and url found in .gitmodules into .git/config.
 107         The key used in .git/config is `submodule.$name.url`.
 108         This command does not alter existing information in .git/config.
 109         You can then customize the submodule clone URLs in .git/config
 110         for your local setup and proceed to 'git submodule update';
 111         you can also just use 'git submodule update --init' without
 112         the explicit 'init' step if you do not intend to customize
 113         any submodule locations.
 114
 115 update::
 116         Update the registered submodules, i.e. clone missing submodules and
 117         checkout the commit specified in the index of the containing repository.
 118         This will make the submodules HEAD be detached unless '--rebase' is
 119         specified or the key `submodule.$name.update` is set to `rebase`.
 120 +
 121 If the submodule is not yet initialized, and you just want to use the
 122 setting as stored in .gitmodules, you can automatically initialize the
 123 submodule with the --init option.
 124
 125 summary::
 126         Show commit summary between the given commit (defaults to HEAD) and
 127         working tree/index. For a submodule in question, a series of commits
 128         in the submodule between the given super project commit and the
 129         index or working tree (switched by --cached) are shown.
 130
 131 foreach::
 132         Evaluates an arbitrary shell command in each checked out submodule.
 133         The command has access to the variables $path and $sha1:
 134         $path is the name of the submodule directory relative to the
 135         superproject, and $sha1 is the commit as recorded in the superproject.
 136         Any submodules defined in the superproject but not checked out are
 137         ignored by this command. Unless given --quiet, foreach prints the name
 138         of each submodule before evaluating the command.
 139         A non-zero return from the command in any submodule causes
 140         the processing to terminate. This can be overridden by adding '|| :'
 141         to the end of the command.
 142 +
 143 As an example, "git submodule foreach 'echo $path `git rev-parse HEAD`' will
 144 show the path and currently checked out commit for each submodule.
 145
 146 sync::
 147         Synchronizes submodules' remote URL configuration setting
 148         to the value specified in .gitmodules.  This is useful when
 149         submodule URLs change upstream and you need to update your local
 150         repositories accordingly.
 151 +
 152 "git submodule sync" synchronizes all submodules while
 153 "git submodule sync -- A" synchronizes submodule "A" only.
 154
 155 OPTIONS
 156 -------
 157 -q::
 158 --quiet::
 159         Only print error messages.
 160
 161 -b::
 162 --branch::
 163         Branch of repository to add as submodule.
 164
 165 --cached::
 166         This option is only valid for status and summary commands.  These
 167         commands typically use the commit found in the submodule HEAD, but
 168         with this option, the commit stored in the index is used instead.
 169
 170 -n::
 171 --summary-limit::
 172         This option is only valid for the summary command.
 173         Limit the summary size (number of commits shown in total).
 174         Giving 0 will disable the summary; a negative number means unlimited
 175         (the default). This limit only applies to modified submodules. The
 176         size is always limited to 1 for added/deleted/typechanged submodules.
 177
 178 -N::
 179 --no-fetch::
 180         This option is only valid for the update command.
 181         Don't fetch new objects from the remote site.
 182
 183 --rebase::
 184         This option is only valid for the update command.
 185         Rebase the current branch onto the commit recorded in the
 186         superproject. If this option is given, the submodule's HEAD will not
 187         be detached. If a a merge failure prevents this process, you will have
 188         to resolve these failures with linkgit:git-rebase[1].
 189         If the key `submodule.$name.update` is set to `rebase`, this option is
 190         implicit.
 191
 192 --reference <repository>::
 193         This option is only valid for add and update commands.  These
 194         commands sometimes need to clone a remote repository. In this case,
 195         this option will be passed to the linkgit:git-clone[1] command.
 196 +
 197 *NOTE*: Do *not* use this option unless you have read the note
 198 for linkgit:git-clone[1]'s --reference and --shared options carefully.
 199
 200 <path>...::
 201         Paths to submodule(s). When specified this will restrict the command
 202         to only operate on the submodules found at the specified paths.
 203         (This argument is required with add).
 204
 205 FILES
 206 -----
 207 When initializing submodules, a .gitmodules file in the top-level directory
 208 of the containing repository is used to find the url of each submodule.
 209 This file should be formatted in the same way as `$GIT_DIR/config`. The key
 210 to each submodule url is "submodule.$name.url".  See linkgit:gitmodules[5]
 211 for details.
 212
 213
 214 AUTHOR
 215 ------
 216 Written by Lars Hjemli <hjemli@gmail.com>
 217
 218 GIT
 219 ---
 220 Part of the linkgit:git[1] suite