Date: Tue, 20 Feb 1996 17:26:04 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
To: Lance Kalzus <kalzus AT KIM DOT NR DOT RES DOT NYU DOT EDU>
Cc: djgpp AT delorie DOT com
Subject: Re: Interrupt trapping
In-Reply-To: <4g9av4$fa2@cmcl2.NYU.EDU>
Message-Id: <Pine.SUN.3.91.960220171502.1163B-100000@is>
Mime-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII


On 19 Feb 1996, Lance Kalzus wrote:

> I have an application which requires me to trap two hardware interrupts.  
> Unfortunately, one of those hardware interrupts is the system timer 
> itself.  I'd like to trap it while my program is running, have it 
> increment a simple counter, and if possible, call the DOS clock handler 
> at an appropriate time (this part isn't strictly necessary, but it _is_ 
> nice to do properly :), and interrupt-return.

You didn't say if you use DJGPP v2 or v1.12.  In any case, you should 
first read Chapter 18 of the DJGPP FAQ list (available as faq102.zip from 
the v1 archives).  Then, there is a nice example of using timer 
interrupts from DJGPP on SimTel mirrors, look in SimTel/msdos/c directory 
for a file called pctime13.zip; it's a good place to start.