Event trapping

 BBS: Inland Empire Archive
Date: 05-30-92 (22:54)             Number: 73
From: MICHAEL MALLEY               Refer#: NONE
  To: JON SPRINGER                  Recvd: NO  
Subj: Event trapping                 Conf: (2) Quik_Bas
JS>JG>     He was wrong.. you can trap it.  Do this:
JS>JG> KEY 20,CHR$(12)+CHR$(83)
JS>JG> ON KEY(20) GOSUB CantReboot

JS>Hmmm...It only traps the delete key on my numeric
JS>keypad...Which is why I'm hoping somebody has some POKEs.
JS>Do you have an extended keyboard?

I'll pop in here real quick to make mention of something that noone has
seemed to notice.  You can trap extended keyes by adding 128 to the scan
code, HOWEVER, you must also set up traps that also check for the
combinations of <Num Lock> and <Caps Lock>.  That means your traps needs
to look something like this:

<Ctrl> + <Alt>
<Ctrl> + <Alt> + <Caps Lock>
<Ctrl> + <Alt> + <Num Lock>
<Ctrl> + <Alt> + <Caps Lock> + <Num Lock>
<Ctrl> + <Alt> + 128
<Ctrl> + <Alt> + <Caps Lock> + 128
<Ctrl> + <Alt> + <Num Lock> + 128
<Ctrl> + <Alt> + <Caps Lock> + <Num Lock> + 128

You *shouldn't* have to trap for the shift keys, because the shifted
<Del> becomes a period, however I haven't tested this theory.
Unfortunately, I know of no memory location that has a flag authorizing
the removal of a warm boot.  I believe that unless you follow these
traps, you would have to write your own interrupt handler for the
keyboard, filtering out combinations of <Ctrl>+<Alt>+<Del>

- Michael  :)

 * SLMR 2.1a * I'm feeling argumentative... *please* contradict me!

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 * Origin: UltraTech - Nashville, TN  (615) 356-0453 {HST} (1:116/30)
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