Date: Sun, 22 Feb 1998 21:09:30 -0500 (EST)
Message-Id: <199802230209.VAA23206@delorie.com>
From: DJ Delorie <dj AT delorie DOT com>
To: spyder AT binary DOT net
CC: djgpp AT delorie DOT com
In-reply-to: <Pine.BSF.3.96.980222192549.18117B-100000@ravine.binary.net>
	(message from Daryl Johnson on Sun, 22 Feb 1998 19:35:56 -0600)
Subject: Re: Need help with timer function
Precedence: bulk


> I am creating a program that administers a test to an individual. The test
> is timed. The problem I am having is with getch(). Even when the timer has

I think you want something like this (untested).  This is similar to
yours, but note the use of kbhit(), which tells you *if* a key has
been hit.  Note also the use of __dpmi_yield() to avoid using 100% of
the CPU.  You may want to look up getkey() and getxkey() as alternates
to getch(), depending on your needs.

#include <time.h>
#include <dpmi.h>
#include <pc.h>
#include <conio.h>

int timed_getch(int seconds)
{
  time_t start, end;
  time(&start);
  while (1) {
    time(&end_time);
    if (end_time - start_time > seconds) return -1;
    if (kbhit()) return getch();
    __dpmi_yield();
  }
}