Clarify documentation of 'vc-responsible-backend' wrt symlinks

* lisp/vc/vc.el (vc-responsible-backend): Clarify that symlinks
are not resolved when the VC backend is reported.

* doc/lispref/files.texi (Truenames): Document
'vc-responsible-backend'.  (Bug#23436)
* doc/emacs/maintaining.texi (Version Control Systems): Fix a
typo.

1 files changed, 5 insertions, 1 deletions

diff --git a/lisp/vc/vc.el b/lisp/vc/vc.el
index ac020d09539..2ddf4e19e1f 100644
--- a/lisp/vc/vc.el
+++ b/lisp/vc/vc.el
@@ -959,7 +959,11 @@ use."
 If FILE is already registered, return the
 backend of FILE.  If FILE is not registered, then the
 first backend in `vc-handled-backends' that declares itself
-responsible for FILE is returned."
+responsible for FILE is returned.
+
+Note that if FILE is a symbolic link, it will not be resolved --
+the responsible backend system for the symbolic link itself will
+be reported."
   (or (and (not (file-directory-p file)) (vc-backend file))
       (catch 'found
         ;; First try: find a responsible backend.  If this is for registration,