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In-reply-to: <20041221212942.746d7b90.lijon@kymatica.com> (message from
	Jonatan Liljedahl on Tue, 21 Dec 2004 21:29:42 -0200)
Subject: Re: DMA and PIO (was Re: Problems with timer interrupt chaining and
 SmartDrv)
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> Date: Tue, 21 Dec 2004 21:29:42 -0200
> From: Jonatan Liljedahl <lijon AT kymatica DOT com>
> 
> > > >> "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.

I was talking about a native Windows build of cat, not a Linux build.

Perhaps the reason is different from what I said, but the fact remains
that the Windows port exits in less than 1 second when its stdout is
redirected to the null device.  The input file is 750MB long, so it
cannot be reading all that in less than a second.  wc on the same
machine takes 20 seconds to read that same file.