From: kgallagh@digi.lonestar.org (Kevin Gallagher)
Newsgroups: gnu.emacs.help
Subject: Re: Help in Demacs
Date: 18 Nov 92 02:46:30 GMT
Organization: DSC Communications Corp, Plano, TX

In article <hm342st.721920493@unidui> hm342st@unidui.uni-duisburg.de (Michael Staats) writes:
>In <9211131423.AA06353@accura_nc.aisg.com> keith%accura_nc@concert.net (Keith B. Kee {AISG} ) writes:
>
>>Hi:
>> I have obtained a copy of demacs 1.20. After hours of installing it, I 
>>finally got it running. However, there are two things that I could not
>>get it to work right. 
>
>>	1) Putting (load-library "bobcat") in my _emacs did not swap the 
>>	   backspace and Del.
>
>Hello,
>the .../lisp/term directory is not in the default load-path.
>Use
>(load-library "term/bobcat")
>instead.

But if (load-library "bobcat") failed to find bobcat.el, it would have
complained by issuing an error message.  My copy of Demacs came with bobcat.el
in the demacs/lisp directory, not the demacs/lisp/term directory.  So I don't
think that this will solve Keith's problem.

I believe that Keith may be misunderstanding what bobcat.el does.  It does NOT
swap the meaning of the Backspace and Del KEYS on the PC keyboard.  It
actually has nothing to do with the PC Del key (or the extended Delete key).
It swaps the C-h ascii character with the DEL ascii character, when seen by
emacs as entered from the keyboard.  The PC BackSpace key normally results in
a C-h being seen by the application program.  Holding the PC control key down
and pressing the PC BackSpace key normally results in a DEL character being
seen by the application program (which many people don't realize).

When bobcat.el is loaded into Demacs, it tells Demacs to treat any C-h
character it sees coming from the keyboard as if a DEL character were sent
from the keyboard, and vice versa.  This results in the BackSpace key (and C-h
entered from the keyboard, using the PC control key and H keys) appearing as a
DEL character to Demacs.  To have Demacs think that a C-h character was
entered from the keyboard, you have to press the PC control key and BackSpace
keys together.

>>	2) I could not get the "mark-command" from my keyboard. I tried
>>	   using ^h-k to help me determine the bindings, and typing
>>	   c-@ on the keyboard gave me this sequence instead: c-@ c-c.
>
>Can't help you with that, on the german keyboard it is a little
>different. But try Control-Space to set the mark.

Some, but not all, keyboards generate a C-@ when Control-Space is entered.
Under ANSI.SYS, on a PC, Control-Space does NOT return a C-@.  Instead, it
simply returns a Space character when Control-Space is entered from the PC
keyboard.  That is, ANSI.SYS ignores the fact that the control key is pressed.

The authors of Demacs clearly have modified the Demacs code to directly detect
when the control key is pressed so that Demacs can choose to interpret
Control-Space as a C-@ (NUL) character, since Demacs cannot depend upon
ANSI.SYS to do this for it.

Unfortunately, on the PC, most PC function and keypad keys generate
two-character sequences, the first of which is C-@.  Therefore, in Demacs, C-@
cannot be bound to set-mark-command (the GNU Emacs default binding) because
C-@ is a prefix-character for most of the PC function and keypad keys.  So,
the authors of Demacs compromised and bound the set-mark-command to the
sequence C-@ C-@.  Thus, to set the mark in Demacs, just press Control-Space
TWICE.

-- 
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Kevin Gallagher        kgallagh@digi.lonestar.org OR ...!uunet!digi!kgallagh
DSC Communications Corporation   Addr: MS 152, 1000 Coit Rd, Plano, TX 75075
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