[PATCHv2] git-submodule.txt: Clarify 'init' and 'add' subcommands.

[worley@alum.mit.edu (Dale R. Worley)]

Describe how 'add' sets the submodule's logical name, which is used in
the configuration entry names.

Clarify that 'init' only sets up the configuration entries for
submodules that have already been added elsewhere.  Describe that
<path> arguments limit the submodules that are configured.

Signed-off-by: Dale Worley <worley@ariadne.com>
---
This patch seems to have all the features that we have discussed:

- Describes how 'add' selects the submodule logical name, including
  the effect of --name.  (My first patch was on a version of Git that
  did not support --name, so I didn't know of it.)

- Corrects description of 'init' to clarify that its behavior is
  driven by the gitlinks recorded in the index, rather than implying
  it is driven by the contents of .gitmodules.

- Describes 'init' behavior to be driven by the index, rather than my
  previous incorrect use of "file tree".  (Of course, gitlinks aren't
  visible in the file tree.)

- Updated text for 'init' is shorter and less technical than my
  previous patch.

- Since "(which were added and committed elsewhere)" is stated in the
  first sentence, I've removed the later sentence explaining that
  submodules must be added before they can be inited.

- Explains the effect of <path> arguments to 'init' subcommand.

 Documentation/git-submodule.txt |    8 ++++++--
 1 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/Documentation/git-submodule.txt b/Documentation/git-submodule.txt
index c99d795..83235c0 100644
--- a/Documentation/git-submodule.txt
+++ b/Documentation/git-submodule.txt
@@ -76,6 +76,8 @@ argument <path> is the relative location for the cloned submodule
 to exist in the superproject. If <path> is not given, the
 "humanish" part of the source repository is used ("repo" for
 "/path/to/repo.git" and "foo" for "host.xz:foo/.git").
+The <path> is also used as the submodule's logical name in its
+configuration entries unless `--name` is used to specify a logical name.
 +
 <repository> is the URL of the new submodule's origin repository.
 This may be either an absolute URL, or (if it begins with ./
@@ -123,8 +125,10 @@ linkgit:git-status[1] and linkgit:git-diff[1] will provide that information
 too (and can also report changes to a submodule's work tree).
 
 init::
-	Initialize the submodules, i.e. register each submodule name
-	and url found in .gitmodules into .git/config.
+	Initialize the submodules recorded in the index (which were
+	added and committed elsewhere) by copying submodule
+	names and urls from .gitmodules to .git/config.
+	Optional <path> arguments limit which submodules will be initialized.
 	It will also copy the value of `submodule.$name.update` into
 	.git/config.
 	The key used in .git/config is `submodule.$name.url`.
-- 
1.7.7.6