Re: Problem with interpretation of <-Backspace key in version 21.2.1

[Rabbe Fogelholm <Rabbe.Fogelholm@era-t.ericsson.se>]

Eli Zaretskii wrote:
> 
> > From: Rabbe Fogelholm <Rabbe.Fogelholm@era-t.ericsson.se>
> > Newsgroups: gnu.emacs.bug
> > Date: Sat, 06 Apr 2002 17:55:46 +0200
> >
> > My setup might be important. The PC runs Red Hat Linux 7.1 and KDE. In
> > that environment I run an xterm (version XFree86 4.0.3(156)). From the
> > xterm session I do an ssh login to a Solaris/SPARC machine that starts a
> > login shell which is 6.10.00 (Astron). From the tcsh prompt I start
> > Emacs with the -nw option.
> 
> It sounds like this is not a bug, but an intended change in behavior,
> which somehow clashes with your xterm/Emacs customizations which were
> optimized for the pre-v21 behavior.
>
> My guess is that your xterm and/or your shell startup files on the
> Solaris side set up the Backspace key to produce the [deletechar]
> escape sequence.  Try using "C-h l" (that's a letter ell, not a digit
> one) to see what does Emacs receive when you press that key.

I don't have any customizations that should affect this. My .emacs file
contained just one thing which was (font-lock-mode 1), and my .Xdefaults
file contained nothing relevant.

> Also, the new function normal-erase-is-backspace-mode might help you
> set this straight.  The description of the related issues in the
> manual, in the sections "Deletion" and "If <DEL> Fails to Delete",
> should also prove useful.
> 
> If all of the above does not help to resolve the problem, or at least
> understand why exactly the behavior changed since Emacs 20.7, please
> report the details that you discovered here.

It turned out that a usable workaround for me is to add this to the
.emacs file:

(if (functionp 'normal-erase-is-backspace-mode)
  (apply 'normal-erase-is-backspace-mode '(0))
)

The code has no effect with older versions of emacs, and sets things
"right" for me with the -nw option in version 21.2.1.

I now realize that this is an intended change in 21.2 (see
<http://www.gnu.org/software/emacs/NEWS.21.2> and search for
normal-erase-is-backspace). Perhaps it makes life easier for some users,
but given my particular setup it caused me a bit of confusion.

--Rabbe Fogelholm