`tramp-handle-vc-registered' is problematic

[Toru TSUNEYOSHI]

Hello.

I think that function `tramp-handle-vc-registered' is problematic.

The reason is that COMMAND

    (mapconcat 'tramp-shell-quote-argument
               tramp-vc-registered-file-names
               " ")

of `tramp-send-command-and-read' become too long (>= 4096 characters)
easily. Indeed, `tramp-send-command-and-read' hangs up often.
(I use "pscp" as the method.)

========================================================================
(defun tramp-handle-vc-registered (file)
  ...

          ;; Send just one command, in order to fill the cache.
          (when tramp-vc-registered-file-names
            (tramp-maybe-send-script
             v
             (format tramp-vc-registered-read-file-names
                     (tramp-get-file-exists-command v)
                     (format "%s -r" (tramp-get-test-command v)))
             "tramp_vc_registered_read_file_names")

            (dolist
                (elt
                 (tramp-send-command-and-read                   ;; <=
                  v                                             ;; <=
                  (format                                       ;; <=
                   "tramp_vc_registered_read_file_names %s"     ;; <=
                   (mapconcat 'tramp-shell-quote-argument       ;; <=
                              tramp-vc-registered-file-names    ;; <=
                              " "))))                           ;; <=

              (tramp-set-file-property
               v (car elt) (cadr elt) (cadr (cdr elt))))))

  ...
  )
========================================================================

Please fix it.
(I fixed it temporarily.)

========================================================================
--- tramp.el.original   2010-08-10 09:40:05.772650400 +0900
+++ tramp.el    2010-08-10 12:02:46.873587600 +0900
@@ -5414,18 +5414,18 @@
                     (format "%s -r" (tramp-get-test-command v)))
             "tramp_vc_registered_read_file_names")
 
-           (dolist
-               (elt
-                (tramp-send-command-and-read
-                 v
-                 (format
-                  "tramp_vc_registered_read_file_names %s"
-                  (mapconcat 'tramp-shell-quote-argument
-                             tramp-vc-registered-file-names
-                             " "))))
+           (mapc
+            (lambda (x)
+              (dolist
+                  (elt
+                   (tramp-send-command-and-read
+                    v
+                    (format
+                     "tramp_vc_registered_read_file_names %s"
+                     (tramp-shell-quote-argument x))))
 
-             (tramp-set-file-property
-              v (car elt) (cadr elt) (cadr (cdr elt))))))
+                (tramp-set-file-property v (car elt) (cadr elt) (cadr (cdr 
elt)))))
+            tramp-vc-registered-file-names)))
 
        ;; Second run.  Now all `file-exists-p' or `file-readable-p'
        ;; calls shall be answered from the file cache.  We unset
========================================================================