Re: tramp (2.0.25); saving remote buffer fails

[Michael Albinus]

address@hidden (Kai Großjohann) writes:

> I hope I have time to debug this soon.

I checked it a little bit (not debugging):

- Clemens seems to use Emacs 21.3.50, according to his messages.

- In files.el, the implementation of backup-buffer has changed (wrt to
  Emacs 21.2, what I use). There's the following code sequence
  (taken from the CVS HEAD of files.el; I'm too lazy for downloading
  Emacs 21.3.50): 

                (let (...
                      (modes (file-modes buffer-file-name)))
                  ;; Actually write the back up file.
                  (condition-case ()
                      (if (or file-precious-flag
    ;                         (file-symlink-p buffer-file-name)
                              backup-by-copying
                              ;; Don't rename a suid or sgid file.
                              (< 0 (logand modes #o6000))
                              ...

The result of `file-modes' isn't checked, and it is expected to be
non-nil. Hmm. 

According to the documentation, this might be correct. On the other
hand, Ange-FTP (and maybe other packages as well) return nil as "don't
know" value.

Kai: could you, please, check in the Emacs mailing list, what's the
correct interpretation? Either nil is a valid return value of
file-modes (that I'ld prefer), than files.el and the Elisp
documentation should be corrected. Or it is an Ange-FTP error.

Best regards, Michael.