bug#21699: 24.5; Bug in backup-buffer-copy and/or set-file-extended-attributes etc [set-file-extended-attributes]

[Eli Zaretskii]

> Date: Mon, 19 Oct 2015 09:38:08 +0300
> From: Eli Zaretskii <eliz@gnu.org>
> Cc: 21699@debbugs.gnu.org
> 
> So after fixing set-file-extended-attributes as you suggest, does the
> problem still happen for you?

Actually, your suggested variant also returns nil for me.  I need
something like this instead:

  (defun set-file-extended-attributes (filename attributes)
    "Set extended attributes of file FILENAME to ATTRIBUTES.

  ATTRIBUTES must be an alist of file attributes as returned by
  `file-extended-attributes'."
    (let (result)
      (dolist (elt attributes)
        (let ((attr (car elt))
              (val (cdr elt)))
          (cond ((eq attr 'acl)
                 (setq result (or result
                                  (set-file-acl filename val))))
                ((eq attr 'selinux-context)
                 (setq result (or result
                                  (set-file-selinux-context filename val)))))))
      result))

With this change, evaluating

 (set-file-extended-attributes "~/.emacs" (file-extended-attributes "~/.emacs")

returns t here.