'git submodule' [--quiet] init [--] [<path>...]
'git submodule' [--quiet] update [--init] [--] [<path>...]
'git submodule' [--quiet] summary [--summary-limit <n>] [commit] [--] [<path>...]
+'git submodule' [--quiet] foreach <command>
+'git submodule' [--quiet] sync [--] [<path>...]
DESCRIPTION
-----------
-Submodules are a special kind of tree entries which refer to a particular tree
-state in another repository. The tree entry describes
-the existence of a submodule with the given name and the exact revision that
-should be used, while an entry in `.gitmodules` file gives the location of
-the repository.
-
-When checked out, submodules will maintain their own independent repositories
-within their directories; the only link between the submodule and the "parent
-project" is the tree entry within the parent project mentioned above.
-
-This command will manage the tree entries and contents of the gitmodules file
-for you, as well as inspecting the status of your submodules and updating them.
-When adding a new submodule to the tree, the 'add' subcommand is to be used.
-However, when pulling a tree containing submodules, these will not be checked
-out by default; the 'init' and 'update' subcommands will maintain submodules
-checked out and at appropriate revision in your working tree. You can inspect
-the current status of your submodules using the 'submodule' subcommand and get
-an overview of changes 'update' would perform using the 'summary' subcommand.
+Submodules allow foreign repositories to be embedded within
+a dedicated subdirectory of the source tree, always pointed
+at a particular commit.
+
+They are not to be confused with remotes, which are meant mainly
+for branches of the same project; submodules are meant for
+different projects you would like to make part of your source tree,
+while the history of the two projects still stays completely
+independent and you cannot modify the contents of the submodule
+from within the main project.
+If you want to merge the project histories and want to treat the
+aggregated whole as a single project from then on, you may want to
+add a remote for the other project and use the 'subtree' merge strategy,
+instead of treating the other project as a submodule. Directories
+that come from both projects can be cloned and checked out as a whole
+if you choose to go that route.
+
+Submodules are composed from a so-called `gitlink` tree entry
+in the main repository that refers to a particular commit object
+within the inner repository that is completely separate.
+A record in the `.gitmodules` file at the root of the source
+tree assigns a logical name to the submodule and describes
+the default URL the submodule shall be cloned from.
+The logical name can be used for overriding this URL within your
+local repository configuration (see 'submodule init').
+
+This command will manage the tree entries and contents of the
+gitmodules file for you, as well as inspect the status of your
+submodules and update them.
+When adding a new submodule to the tree, the 'add' subcommand
+is to be used. However, when pulling a tree containing submodules,
+these will not be checked out by default;
+the 'init' and 'update' subcommands will maintain submodules
+checked out and at appropriate revision in your working tree.
+You can briefly inspect the up-to-date status of your submodules
+using the 'status' subcommand and get a detailed overview of the
+difference between the index and checkouts using the 'summary'
+subcommand.
COMMANDS
add::
Add the given repository as a submodule at the given path
to the changeset to be committed next to the current
- project: the current project is termed termed the "superproject".
+ project: the current project is termed the "superproject".
+
This requires two arguments: <repository> and <path>.
+
repository. This command is the default command for 'git-submodule'.
init::
- Initialize the submodules, i.e. register in .git/config each submodule
- name and url found in .gitmodules. The key used in .git/config is
- `submodule.$name.url`. This command does not alter existing information
- in .git/config.
+ Initialize the submodules, i.e. register each submodule name
+ and url found in .gitmodules into .git/config.
+ The key used in .git/config is `submodule.$name.url`.
+ This command does not alter existing information in .git/config.
+ You can then customize the submodule clone URLs in .git/config
+ for your local setup and proceed to 'git submodule update';
+ you can also just use 'git submodule update --init' without
+ the explicit 'init' step if you do not intend to customize
+ any submodule locations.
update::
Update the registered submodules, i.e. clone missing submodules and
in the submodule between the given super project commit and the
index or working tree (switched by --cached) are shown.
+foreach::
+ Evaluates an arbitrary shell command in each checked out submodule.
+ The command has access to the variables $path and $sha1:
+ $path is the name of the submodule directory relative to the
+ superproject, and $sha1 is the commit as recorded in the superproject.
+ Any submodules defined in the superproject but not checked out are
+ ignored by this command. Unless given --quiet, foreach prints the name
+ of each submodule before evaluating the command.
+ A non-zero return from the command in any submodule causes
+ the processing to terminate. This can be overridden by adding '|| :'
+ to the end of the command.
++
+As an example, "git submodule foreach 'echo $path `git rev-parse HEAD`' will
+show the path and currently checked out commit for each submodule.
+
+sync::
+ Synchronizes submodules' remote URL configuration setting
+ to the value specified in .gitmodules. This is useful when
+ submodule URLs change upstream and you need to update your local
+ repositories accordingly.
++
+"git submodule sync" synchronizes all submodules while
+"git submodule sync -- A" synchronizes submodule "A" only.
+
OPTIONS
-------
-q::
(the default). This limit only applies to modified submodules. The
size is always limited to 1 for added/deleted/typechanged submodules.
-<path>::
- Path to submodule(s). When specified this will restrict the command
+<path>...::
+ Paths to submodule(s). When specified this will restrict the command
to only operate on the submodules found at the specified paths.
(This argument is required with add).