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] [--] <repository> <path>
  13 'git submodule' [--quiet] status [--cached] [--] [<path>...]
  14 'git submodule' [--quiet] init [--] [<path>...]
  15 'git submodule' [--quiet] update [--init] [--] [<path>...]
  16 'git submodule' [--quiet] summary [--summary-limit <n>] [commit] [--] [<path>...]
  17 'git submodule' [--quiet] foreach <command>
  18
  19
  20 DESCRIPTION
  21 -----------
  22 Submodules allow foreign repositories to be embedded within
  23 a dedicated subdirectory of the source tree, always pointed
  24 at a particular commit.
  25
  26 They are not to be confused with remotes, which are meant mainly
  27 for branches of the same project; submodules are meant for
  28 different projects you would like to make part of your source tree,
  29 while the history of the two projects still stays completely
  30 independent and you cannot modify the contents of the submodule
  31 from within the main project.
  32 If you want to merge the project histories and want to treat the
  33 aggregated whole as a single project from then on, you may want to
  34 add a remote for the other project and use the 'subtree' merge strategy,
  35 instead of treating the other project as a submodule. Directories
  36 that come from both projects can be cloned and checked out as a whole
  37 if you choose to go that route.
  38
  39 Submodules are composed from a so-called `gitlink` tree entry
  40 in the main repository that refers to a particular commit object
  41 within the inner repository that is completely separate.
  42 A record in the `.gitmodules` file at the root of the source
  43 tree assigns a logical name to the submodule and describes
  44 the default URL the submodule shall be cloned from.
  45 The logical name can be used for overriding this URL within your
  46 local repository configuration (see 'submodule init').
  47
  48 This command will manage the tree entries and contents of the
  49 gitmodules file for you, as well as inspect the status of your
  50 submodules and update them.
  51 When adding a new submodule to the tree, the 'add' subcommand
  52 is to be used.  However, when pulling a tree containing submodules,
  53 these will not be checked out by default;
  54 the 'init' and 'update' subcommands will maintain submodules
  55 checked out and at appropriate revision in your working tree.
  56 You can briefly inspect the up-to-date status of your submodules
  57 using the 'status' subcommand and get a detailed overview of the
  58 difference between the index and checkouts using the 'summary'
  59 subcommand.
  60
  61
  62 COMMANDS
  63 --------
  64 add::
  65         Add the given repository as a submodule at the given path
  66         to the changeset to be committed next to the current
  67         project: the current project is termed the "superproject".
  68 +
  69 This requires two arguments: <repository> and <path>.
  70 +
  71 <repository> is the URL of the new submodule's origin repository.
  72 This may be either an absolute URL, or (if it begins with ./
  73 or ../), the location relative to the superproject's origin
  74 repository.
  75 +
  76 <path> is the relative location for the cloned submodule to
  77 exist in the superproject. If <path> does not exist, then the
  78 submodule is created by cloning from the named URL. If <path> does
  79 exist and is already a valid git repository, then this is added
  80 to the changeset without cloning. This second form is provided
  81 to ease creating a new submodule from scratch, and presumes
  82 the user will later push the submodule to the given URL.
  83 +
  84 In either case, the given URL is recorded into .gitmodules for
  85 use by subsequent users cloning the superproject. If the URL is
  86 given relative to the superproject's repository, the presumption
  87 is the superproject and submodule repositories will be kept
  88 together in the same relative location, and only the
  89 superproject's URL need be provided: git-submodule will correctly
  90 locate the submodule using the relative URL in .gitmodules.
  91
  92 status::
  93         Show the status of the submodules. This will print the SHA-1 of the
  94         currently checked out commit for each submodule, along with the
  95         submodule path and the output of 'git-describe' for the
  96         SHA-1. Each SHA-1 will be prefixed with `-` if the submodule is not
  97         initialized and `+` if the currently checked out submodule commit
  98         does not match the SHA-1 found in the index of the containing
  99         repository. This command is the default command for 'git-submodule'.
 100
 101 init::
 102         Initialize the submodules, i.e. register each submodule name
 103         and url found in .gitmodules into .git/config.
 104         The key used in .git/config is `submodule.$name.url`.
 105         This command does not alter existing information in .git/config.
 106         You can then customize the submodule clone URLs in .git/config
 107         for your local setup and proceed to 'git submodule update';
 108         you can also just use 'git submodule update --init' without
 109         the explicit 'init' step if you do not intend to customize
 110         any submodule locations.
 111
 112 update::
 113         Update the registered submodules, i.e. clone missing submodules and
 114         checkout the commit specified in the index of the containing repository.
 115         This will make the submodules HEAD be detached.
 116 +
 117 If the submodule is not yet initialized, and you just want to use the
 118 setting as stored in .gitmodules, you can automatically initialize the
 119 submodule with the --init option.
 120
 121 summary::
 122         Show commit summary between the given commit (defaults to HEAD) and
 123         working tree/index. For a submodule in question, a series of commits
 124         in the submodule between the given super project commit and the
 125         index or working tree (switched by --cached) are shown.
 126
 127 foreach::
 128         Evaluates an arbitrary shell command in each checked out submodule.
 129         The command has access to the variables $path and $sha1:
 130         $path is the name of the submodule directory relative to the
 131         superproject, and $sha1 is the commit as recorded in the superproject.
 132         Any submodules defined in the superproject but not checked out are
 133         ignored by this command. Unless given --quiet, foreach prints the name
 134         of each submodule before evaluating the command.
 135         A non-zero return from the command in any submodule causes
 136         the processing to terminate. This can be overridden by adding '|| :'
 137         to the end of the command.
 138 +
 139 As an example, "git submodule foreach 'echo $path `git rev-parse HEAD`' will
 140 show the path and currently checked out commit for each submodule.
 141
 142
 143 OPTIONS
 144 -------
 145 -q::
 146 --quiet::
 147         Only print error messages.
 148
 149 -b::
 150 --branch::
 151         Branch of repository to add as submodule.
 152
 153 --cached::
 154         This option is only valid for status and summary commands.  These
 155         commands typically use the commit found in the submodule HEAD, but
 156         with this option, the commit stored in the index is used instead.
 157
 158 -n::
 159 --summary-limit::
 160         This option is only valid for the summary command.
 161         Limit the summary size (number of commits shown in total).
 162         Giving 0 will disable the summary; a negative number means unlimited
 163         (the default). This limit only applies to modified submodules. The
 164         size is always limited to 1 for added/deleted/typechanged submodules.
 165
 166 <path>...::
 167         Paths to submodule(s). When specified this will restrict the command
 168         to only operate on the submodules found at the specified paths.
 169         (This argument is required with add).
 170
 171 FILES
 172 -----
 173 When initializing submodules, a .gitmodules file in the top-level directory
 174 of the containing repository is used to find the url of each submodule.
 175 This file should be formatted in the same way as `$GIT_DIR/config`. The key
 176 to each submodule url is "submodule.$name.url".  See linkgit:gitmodules[5]
 177 for details.
 178
 179
 180 AUTHOR
 181 ------
 182 Written by Lars Hjemli <hjemli@gmail.com>
 183
 184 GIT
 185 ---
 186 Part of the linkgit:git[1] suite