bug#49193: Document require-final-newline vs. readonly files

[Michael Heerdegen]

Eli Zaretskii <eliz@gnu.org> writes:

> > From: 積丹尼 Dan Jacobson <jidanni@jidanni.org>
> > Cc: 49193@debbugs.gnu.org
> > Date: Thu, 24 Jun 2021 03:22:22 +0800
> > 
> > EZ> There's nothing to mention, because this feature doesn't change how
> > EZ> saving to an unwritable file behaves in Emacs.  The feature works on
> > EZ> the buffer text, not on the buffer's file.
> > 
> > Ah, that clears things up.
> > So please mention that.
>
> I don't see a reason to mention that feature A doesn't change how
> feature B works, for every combination of A and B.

If you want a second opinion: That's not the source of my confusion
about the text:

| If the value is ‘visit’, Emacs adds a newline at the end of any file
| that doesn’t have one, just after it visits the file...

But that's not true, is it?  The file is not touched.  Is the newline
still added to the file's buffer?  Or not even that (because the buffer
is read-only)?

Would

| [...] Emacs adds a newline at the end of any file's buffer that
| doesn’t have one, just after it visits the file...

be clearer?


Thanks,

Michael.