From: J DOT Rouwe AT cpedu DOT RUG DOT NL
Date: Wed, 06 Mar 1996 02:11:54 +0100
To: martynas DOT kunigelis AT VM DOT KTU DOT LT, djgpp AT delorie DOT COM
Message-id: <199603060111.CAA21602@indy3.cpedu.rug.nl>
Content-transfer-encoding: 7BIT
Apparently-To: djgpp AT delorie DOT com
Apparently-To: martynas DOT kunigelis AT VM DOT KTU DOT LT

Martynas Kunigelis wrote:

>  After my announcement of `mkkbd1.zip', my keyboard interrupt handler, I have
> received a bug (actually, a crash) report. I have no idea why it happens. I
> feel extremely ashamed and dumb. I have tested it multiple times under
> CWSDPMI
> OS/2 and Windows and it worked. I am now asking someone from DJGPP team to
> remove the buggy(?) zip from SimTel, or maybe C. Sandmann (who is I think a
> DPMI expert after all) could have a look at the code (please??!!). I
> apologize
> possibly] incorrect information.
> 
>  Now I have a question: Eli Zaretskii stated, that once I hook the keyboard
> interrupt and do not chain, keyboard is mine forever, even if the key is
> pressed while CPU is in real mode. However, while testing my above mentioned
> handler, I made a loop of fread()s, which implied, I think, switching to
> real
> mode, and *even with no chaining I was able to break the loop with crtl-c*!
> Why on earth? (whoops, I meant PM interrupt at the beginning of this
> paragrph.)
> 
> P.S. I think crashes in example.c from mkkbd1.zip could be caused by as's
> bug-
>  well, there is *some* possibility ]
>
> ashamed] Martynas Kunigelis

I just used your code for my own program because I'm porting it to gcc.
Before that I had a real mode keyboard handler and there was only one big
difference between the two: I've read somewhere that you should also
acknoledge the keyboard controller (but I don't remember where because the
old code is already 2 years old), so perhaps some keyboards need this
acknoledge (mine doesn't seem to care). The code to acknoledge the keyboard
is:

                inb     $0x61, %al                 
                movb    %al, %ah
                orb     $0x80, %al
                outb    %al, $0x61
                movb    %ah, %al
                outb    %al, $0x61
 
Maybe this is your problem....

Jorrit Rouwe     
j DOT rouwe AT cpedu DOT rug DOT nl