Re: BS changed to give ^? instead of ^H?
Paul Smith wrote:
>
> %% Isaac To <kkto@csis.hku.hk> writes:
>
> >>>>>> "Paul" == Paul Smith <pausmith@nortelnetworks.com> writes:
>
> Paul> If I use bash and C-q BS, or emacs -q -nw to start it within the
> Paul> terminal and use C-q BS, it shows that they key typed is ^? and
> Paul> not ^H as it should be.
>
> it> Who say it "should be" ^H?
>
> I do.
>
> I've been using UNIX for 18 years. I've used X for much of that time.
> I've even used actual vt100 terminals (although it was very long ago).
> I've worked on everything from Ultrix to DG-UX to Solaris to Linux and
> many more in between.
>
> Pressing the backspace key in all these systems generates a ^H
> character. The delete key generates ^?. Except Linux, now.
>
> it> Even the default text console will. give you ^? rather than ^H
> it> when you press backspace. In Emacs, ^H is a prefix character for
> it> "help" rather than binding to "delete-backward-char". If the ^H
> it> binding is made to X terminal programs, Emacs users will find that
> it> pressing backspace leave them a prompt asking for a key to specify
> it> what help he want, rather than deleting one character on the left
> it> of the cursor.
>
> I know all about this issue; I've used Emacs for 14+ years. But, I want
> to know how to make backspace send ^H.
>
> it> If any environment by default sends ^H rather than DEL (i.e., ^?)
> it> when you press BackSpace, then you have to file bug against that
> it> environment. The only one that this won't work is the one that
> it> you have no capability to file a bug against (i.e.,
> it> MS-Windows...).
>
> So, should I submit bugs against Solaris, HP-UX, AIX, etc. etc. so that
> when I telnet to those systems from my Linux box my keybindings work
> properly, more/less work properly, vi works properly, etc. (luckily I
> use bash as my shell which has the very sensible behavior of treating
> backspace and DEL identically)?
>
> I think not. Linux is in the minority here and my preference is to
> change Linux to work the "traditional" way rather than customize all the
> others.
>
> Paul> Looking at xmodmap -pke shows that keycode 22 emits backspace, and
> Paul> xev shows that the BS key is sending the backspace keysym.
>
> it> The BackSpace keysym is a keysym, not a keycode.
>
> Yes, that's why I said "keycode 22" and "the backspace keysym".
>
> it> If you look down, you'll find that the keycode is said to be '"'.
> it> Of course, this is not really the case. It actually want to say
> it> the keycode is ^?, and enclose it between double quotes. But the
> it> ^? actually deletes the leading double quote.
>
> I don't understand this at all... the keycode for backspace is 22, not
> ^?, and xmodmap -pke doesn't generate output in quotes.
>
> Paul> Where should I look for the cause of this? I need BS to give ^H,
> Paul> like it always used to do.
>
> it> It "always" used to send DEL, unless your configuration is wrong.
> it> The "always" means something that is back as far as around the
> it> "bo" (i.e., Debian 1.3) days. Now it is probably time to fix your
> it> stty so that it accepts ^? rather than ^H.
>
> I don't want to do that. I want to change my settings back to what they
> were up until a month or two ago. I use many different system types
> and, as I said above, it's far simpler for me to change Linux back to
> work like all the others than it is to try to change all those other
> systems and applications to work like Linux.
>
> it> There is an exception. Until recently, the gnome-terminal
> it> incorrectly sends ^H rather than DEL on receiving BackSpace
>
> I've never used gnome-terminal. I use rxvt almost exclusively. Maybe a
> few xterms by accident.
>
> So, something changed in the rxvt/xterm builds? I checked all the
> app-defaults and couldn't find anything. Do I have to recompile them
> locally?
There's a detailed explanation of backspace/delete key problems
and fixes in /usr/doc/xfree86-common/FAQ.gz
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