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Mail Archives: djgpp/2004/12/21/15:27:22

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Date: Tue, 21 Dec 2004 21:29:42 -0200
From: Jonatan Liljedahl <lijon AT kymatica DOT com>
To: djgpp AT delorie DOT com
Subject: Re: DMA and PIO (was Re: Problems with timer interrupt chaining and
SmartDrv)
Message-Id: <20041221212942.746d7b90.lijon@kymatica.com>
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On Tue, 21 Dec 2004 21:43:02 +0200
"Eli Zaretskii" <eliz AT gnu DOT org> wrote:

> > From: Martin Str|mberg <ams AT speedy DOT ludd DOT ltu DOT se>
> > Date: 21 Dec 2004 08:11:17 GMT
> > 
> > >> "cat file >/dev/null"?
> > 
> > > This reads _and_ writes the file.  I want something that just
> > > reads it.
> > 
> > It doesn't write it to disk. At least I hope so.
> 
> In fact, it doesn't do anything it all: it is smart enough to see that
> stdout is redirected to the null device, and exits immediately.  So
> it's no good for a test I wanted to do.

That's not true. At least not on my system (Linux 2.6.6 with cat version
5.2.1 (coreutils)).
cat just reads the file until end or user interrupt. Try this and you'll
see:

cat /dev/zero > /dev/null

(the zero device acts like an eternal file filled with zero's)

/Jonatan    -=( http://kymatica.com )=-

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