- Like `-u`, but match <pathspec> against files in the
- working tree in addition to the index. That means that it
- will find new files as well as staging modified content and
- removing files that are no longer in the working tree.
+ Update the index not only where the working tree has a file
+ matching <pathspec> but also where the index already has an
+ entry. This adds, modifies, and removes index entries to
+ match the working tree.
++
+If no <pathspec> is given, the current version of Git defaults to
+"."; in other words, update all files in the current directory
+and its subdirectories. This default will change in a future version
+of Git, hence the form without <pathspec> should not be used.