Path: utzoo!mnetor!uunet!mcvax!philmds!leo
From: leo@philmds.UUCP (Leo de Wit)
Newsgroups: comp.sys.atari.st
Subject: Re: st keyboard buffering
Message-ID: <480@philmds.UUCP>
Date: 6 May 88 10:02:42 GMT
References: <4215@dasys1.UUCP> <478@philmds.UUCP> <4694@batcomputer.tn.cornell.edu>
Reply-To: leo@philmds.UUCP (L.J.M. de Wit)
Organization: Philips I&E DTS Eindhoven
Lines: 40
Keywords: keyboard input Crawcin Bconin

In article <4694@batcomputer.tn.cornell.edu> braner@tcgould.tn.cornell.edu (braner) writes:
>In article <478@philmds.UUCP> leo@philmds.UUCP (L.J.M. de Wit) writes:
>>Here's how keyboard buffering is done (at least I thought so ...) :
>> ...[stuff deleted]...
>>    for (i = iop->ibufhead; i != iop->ibuftail; ) { 
>- note that what "they" call head and tail may be the reverse of what you
> (or I, anyway) would call them...

Agree, but I got (a hint for) the names from Data Becker's Atari ST Intern.
I think with a circular buffer, a reader and a writer it's anyway a question
whose side you're on.

>>    for (i = iop->ibufhead; i != iop->ibuftail; ) { 
>>        if (*(int *)(iop->ibuf + i) == CONTROLC) {
>- this may fail if "conterm" is set so that the kbdshift info is in the top
> byte of the top word.  Better use:
>	if (((*(int *)(iop->ibuf + i)) & 0xFF00FF) == CONTROLC)
>	                               ^^^^^^^^^^

Still better maybe:
    for (i = iop->ibufhead; i != iop->ibuftail; ) { 
        if (((*(int *)(iop->ibuf + i)) & 0xFF0000) == CONTROLC)
the ascii bindings may be changed by an xbios call, it's safer to use just
the scancode. But thanks for the correction, anyway!

>  Better to write code like this:
>	#define WORD int	/* this is for megamax */
>	... WORD ...		/* all through the code where it matters */
>  (Makes it a lot easier to port to another compiler.)

or to use:
#include "portab.h"
which just includes such definitions (at least for Lattice there's such a file).

>- Moshe Braner.  (YAFIYGI) (You asked for it, you got it.) (TeX)
>(Still looking for a used 520ST system)

I use one. A plus that is (520 ST++ :=)

        Leo (C-ing is believing).