dired can't operate on '.' or '..'

[Chris Moore]

I used to be able to run commands on '.' and '..' in a dired buffer,
but now I get an error if I try:

  Debugger entered--Lisp error: (error "Cannot operate on `.' or `..'")
    signal(error ("Cannot operate on `.' or `..'"))
    error("Cannot operate on `.' or `..'")
    dired-get-filename(t)
    dired-get-marked-files(t nil)

I moved the cursor to the line with the '.' directory on it and hit
"!" to try to run a command on '.'.  I wanted to run "du -k", for
example, to get a recursive listing of direcoty sizes from here
down.  This used to work but now it doesn't.  It looks like this
might have been done deliberately, but I found it useful to be able
to operate on '.' in dired.

Chris.

In GNU Emacs 21.3.50.1 (i386-mingw-nt5.1.2600)
 of 2003-10-01 on CHRISLAP
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