'git submodule' [--quiet] init [--] [<path>...]
'git submodule' [--quiet] deinit [-f|--force] [--] <path>...
'git submodule' [--quiet] update [--init] [--remote] [-N|--no-fetch]
- [-f|--force] [--rebase] [--reference <repository>] [--depth <depth>]
- [--merge] [--recursive] [--] [<path>...]
+ [-f|--force] [--rebase|--merge|--checkout] [--reference <repository>]
+ [--depth <depth>] [--recursive] [--] [<path>...]
'git submodule' [--quiet] summary [--cached|--files] [(-n|--summary-limit) <n>]
[commit] [--] [<path>...]
'git submodule' [--quiet] foreach [--recursive] <command>
update::
Update the registered submodules, i.e. clone missing submodules and
- checkout the commit specified in the index of the containing repository.
- This will make the submodules HEAD be detached unless `--rebase` or
- `--merge` is specified or the key `submodule.$name.update` is set to
- `rebase`, `merge` or `none`. `none` can be overridden by specifying
- `--checkout`. Setting the key `submodule.$name.update` to `!command`
- will cause `command` to be run. `command` can be any arbitrary shell
- command that takes a single argument, namely the sha1 to update to.
+ checkout the commit specified in the index of the containing
+ repository. The update mode defaults to `checkout`, but can be
+ configured with the `submodule.<name>.update` setting or the
+ `--rebase`, `--merge`, or `--checkout` options.
++
+For updates that clone missing submodules, checkout-mode updates will
+create submodules with detached HEADs; all other modes will create
+submodules with a local branch named after `submodule.<path>.branch`.
++
+For updates that do not clone missing submodules, the submodule's HEAD
+is only touched when the remote reference does not match the
+submodule's HEAD (for none-mode updates, the submodule is never
+touched). The remote reference is usually the gitlinked commit from
+the superproject's tree, but with `--remote` it is the upstream
+subproject's `submodule.<name>.branch`. This remote reference is
+integrated with the submodule's HEAD using the specified update mode.
+For checkout-mode updates, that will result in a detached HEAD. For
+rebase- and merge-mode updates, the commit referenced by the
+submodule's HEAD may change, but the symbolic reference will remain
+unchanged (i.e. checked-out branches will still be checked-out
+branches, and detached HEADs will still be detached HEADs). If none
+of the builtin modes fit your needs, set `submodule.<name>.update` to
+`!command` to configure a custom integration command. `command` can
+be any arbitrary shell command that takes a single argument, namely
+the sha1 to update to.
+
If the submodule is not yet initialized, and you just want to use the
setting as stored in .gitmodules, you can automatically initialize the
fetches the submodule's remote repository before calculating the
SHA-1. If you don't want to fetch, you should use `submodule update
--remote --no-fetch`.
++
+Use this option to integrate changes from the upstream subproject with
+your submodule's current HEAD. Alternatively, you can run `git pull`
+from the submodule, which is equivalent except for the remote branch
+name: `update --remote` uses the default upstream repository and
+`submodule.<name>.branch`, while `git pull` uses the submodule's
+`branch.<name>.merge`. Prefer `submodule.<name>.branch` if you want
+to distribute the default upstream branch with the superproject and
+`branch.<name>.merge` if you want a more native feel while working in
+the submodule itself.
-N::
--no-fetch::