Date: Tue, 11 Jul 95 13:22:48 EST
From: dpsm AT lubrizol DOT com
Cc: djgpp AT sun DOT soe DOT clarkson DOT edu
Subject: Re[2]: Problem with keyboard and sound

> > Keyboard input using int86 is unreliable after a BEL character is written 
? > to the console using write(1, "\007", 1);.

> Can you elaborate?  What exactly does ``unreliable'' mean?  And what
> functions of which interrupt do you use with int86() to read the
> keyboard?


The functions are int 0x16 ah=0x10 and int 0x16 ah=0x11  They are used in 
msdoc.c from GNU Emacs.

The problem is in GNU emacs.  After a bell, keys return ^@ and then a character.

Make sure visible bell is off.   (setq visible-bell nil)
   Make a bell, say previous-line at the top of the buffer.
   (I have describe key-bound to f4)
   Press f4. Press up.
   returns "C-@ runs the command set-mark-command"
   Press f4. (nothing else!)
   returns "H runs the command self-insert-command"


Emacs normally makes a bell with write(1, "\007", 1).  If I use visible-bell or 
use sound();delay();nosound();, I never have this problem.


Other people on this mailing list have mentioned similar wierdness.

I might be in emacs.  I don't think so though.  I guess I need to code up a 
small program to demonstrate the problem.


Dale