How plain (non-dir!) file gets marked "[(dired by name)]"?

How plain (non-dir!) file gets marked "[(dired by name)]"?

[David Combs]

      [Note: I'm using "/opt/sfw/share/emacs/21.2/".]

I have no idea how I might of caused this -- making emacs think of
a regular file as "[(dired by name)]".

Ideas?

--- ok, here's the code (from dired.el):

| (defun dired-sort-set-modeline ()
|   ;; Set modeline display according to dired-actual-switches.
|   ;; Modeline display of "by name" or "by date" guarantees the user a
|   ;; match with the corresponding regexps.  Non-matching switches are
|   ;; shown literally.
|   (setq mode-name
| 	(let (case-fold-search)
| 	  (cond ((string-match dired-sort-by-name-regexp dired-actual-switches)
| 		 "Dired by name")
| 		((string-match dired-sort-by-date-regexp dired-actual-switches)
| 		 "Dired by date")
| 		(t
| 		 (concat "Dired " dired-actual-switches)))))
|   (force-mode-line-update))
|
| (defun dired-sort-toggle-or-edit (&optional arg)
|   "Toggle between sort by date/name and refresh the dired buffer.

(1) What are these switches?  (C-h v  couldn't see: dead)

(2) What problem does this fix (ie, why is it *done*?):

|   ;; Modeline display of "by name" or "by date" guarantees the user a
|   ;; match with the corresponding regexps.  Non-matching switches are
|   ;; shown literally.