bug#7289: Tramp changes ownership of remote file when saving

[Michael Albinus <michael.albinus@gmx.de>]

Stefan Monnier <monnier@iro.umontreal.ca> writes:

> 2 problems with this patch:
> - (put <var> 'permanent-local t) should *never* be in such a function.
>   It's a top-level operation that has global effects and belongs right
>   next to the var's defvar.

I want to have `backup-by-copying-when-mismatch' buffer local. If I set
it in `insert-file-contents' (via `make-local-variable'), it is not kept
buffer local in that buffer. How could I achieve this otherwise?

> - This makes it impossible to choose backup-by-copying-when-mismatch=nil
>   when accessing such remote files, whereas for local files accessed by
>   root a (setq backup-by-copying-when-mismatch nil) in the .emacs will
>   do the trick.

D'accord. We would need another way for the user to express his
wish. Maybe there shall be also other values but only than nil and t.

> A simpler solution would be to change the default value of
> backup-by-copying-when-mismatch to t for everyone rather than just
> for root.  I don't know what would the objections to this.

From my pov it would be acceptable, but I don't know how people see
it. And we should check what it does mean for remote files, because they
tend to "mismatch" more often.

>         Stefan

Best regards, Michael.