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Date: Mon, 23 May 2016 00:54:14 +0200
From: Joerg Sonnenberger <joerg@bec.de>
To: freebsd-hackers@freebsd.org
Subject: Re: read(2) and thus bsdiff is limited to 2^31 bytes
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On Sun, May 22, 2016 at 10:54:30PM +0200, Dirk Engling wrote:
> When trying to bsdiff two DVD images, I noticed it failing due to
> read(2) returning EINVAL to the tool. man 2 read says, this would only
> happen for a negative value for fildes, which clearly was not true.

I would classify that as implementation bug. It seems perfectly sensible
to turn overly large requests into a short read/write, even for blocking
files. But erroring out seems to be quite wrong to me.

Joerg