Path: utzoo!mnetor!uunet!lll-winken!lll-lcc!ames!pasteur!agate!ig!uwmcsd1!tut.cis.ohio-state.edu!ut-sally!nather
From: nather@ut-sally.UUCP (Ed Nather)
Newsgroups: comp.sys.ibm.pc
Subject: Re: Checking for KBD input in "raw" mode
Message-ID: <10489@ut-sally.UUCP>
Date: 26 Feb 88 17:59:46 GMT
References: <8281@eddie.MIT.EDU>
Organization: U. Texas CS Dept., Austin, Texas
Lines: 19

In article <8281@eddie.MIT.EDU>, jbs@eddie.MIT.EDU (Jeff Siegal) writes:
> I am attempting to use "raw" mode to read keyboard input without
> interference from DOS processing of special chars (^C, ^S, etc.) I
> find that reading chars works fine (DOS does not interfere), but if
> attempt to use DOS function 0BH to check the keyboard input status,
> DOS processes special chars like ^C even though raw mode seems to be
> properly set.  Is there something I am missing, or does this simply
> not work as I would like.

The DOS function 0Bh works fine so long as there has been no input;  If,
however, it sees a Ctrl-C it aborts the program unilaterally, without
waiting for your program to decide what to do.

I had to write a keyboard intercept routine to keep it from doing that.  0Bh
works fine if it never sees a Ctrl-C.  It's rotten design on somebody's part.
-- 
Ed Nather
Astronomy Dept, U of Texas @ Austin
{allegra,ihnp4}!{noao,ut-sally}!utastro!nather
nather@astro.AS.UTEXAS.EDU