From: sarahann DOT jackson AT ntlworld DOT com (Kevan Roberts)
Newsgroups: comp.os.msdos.djgpp
Subject: Re: DJGPP Interrupt programs running under Win98 Console
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References: <MPG DOT 152d9471aac5b554989689 AT news DOT ntlworld DOT com> <2110-Thu29Mar2001220437+0200-eliz AT is DOT elta DOT co DOT il>
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Date: Fri, 30 Mar 2001 19:27:21 +0100
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In article <2110-Thu29Mar2001220437+0200-eliz AT is DOT elta DOT co DOT il>, 
eliz AT is DOT elta DOT co DOT il says...
> > From: sarahann DOT jackson AT ntlworld DOT com (Kevan Roberts)
> > Newsgroups: comp.os.msdos.djgpp
> > Date: Thu, 29 Mar 2001 19:51:25 +0100
> > 
> > I am experiencing some strange effects with djgpp interrupt handler 
> > program running under a DOS Console window in Windows 98:
> > 
> > I have chained my own interrupt handler onto the timer and keyboard 
> > interrupt - but the interrupt routine only seems to get called when the 
> > console running the program is running in the foreground.
> 
> This is a Windows ``feature'': only a program that is in the
> foreground gets the timer interrupts.  Programs which run in the
> background get only a very small portion (about 10%) of the timer
> interrupts.  That's multitasking, Bill Gates style.
> 
I'm still confused - I'd naievely assumed I'd chained onto the one and 
only hardware timer interrupt in Windows. This interrupt occurs whether 
my program is in the foreground or background. This can only mean that 
I've registered a 'virtual' handler that in reality is managed by 
Windows. Is this right??