Re: master b8062be 3/5: Remove some compat code from eudc-bob.el

[Eli Zaretskii <eliz@gnu.org>]

> From: Stefan Monnier <monnier@iro.umontreal.ca>
> Cc: emacs-devel@gnu.org
> Date: Thu, 13 Aug 2020 10:23:57 -0400
> 
> > And why does that matter in the case in point?
> 
> No idea, but before removing that code we would have to find out why it
> *doesn't* matter.

It's quite clear that the code wants to put on disk the exact binary
stream it received.

> >> > (And it's wrong to use 'binary' for producing files that will
> >> > be processed by programs other than Emacs, because 'binary' spills out
> >> > the Emacs internal representation of characters.)
> >> It's definitely not wrong for unibyte buffers where there's no "internal
> >> representation of characters" that can spill out ;-)
> > We cannot know that in general.
> 
> Yes, we do: unibyte buffers have no "internal representation of
> characters" that can spill out.

In unibyte buffers the coding-system doesn't matter.

> To me `binary` is *the* coding-system to use when you have bytes and
> want to write them in a file (and same when you want to read the *bytes*
> of a file into a buffer).

For a unibyte buffer, it doesn't matter.  For a multibyte buffer, it's
dangerous.