Re: Preserve permissions after backup?

[Richard Stallman]

    A Tramp user is reporting that the permissions of a root-owned file
    change after he edits it with Tramp (the su method).  I'm guessing
    that's because Tramp does backup by renaming and creates a new file
    with default permissions.

    Is there some machinery in Emacs which is designed to prevent things
    like this from happening?

Yes.  The functions to save the file are supposed to record the permissions
of the old file and apply them to the new file.  This must
be malfunctioning with Tramp.