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Date: Tue, 9 Jan 2007 04:04:45 -0800
From: Christopher Layne <clayne AT anodized DOT com>
To: cygwin AT cygwin DOT com
Subject: Re: 1.7.0 CVS mmap failure
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Real quick here and I'll follow up tomorrow. I don't get SIGSEGV
in my application ever. I get an error back from mmap saying it
cannot allocate memory when i'm simply trying to open a small
file! The original events ere posted up in that first part of
the strace - which is unmodified original behavior. Things did not
start happening UNTIL the MEM_TOP_DOWN change.

My code does not do ANYTHING out of the ordinary that it wasn't
doing before and working completely fine with.

On Tue, Jan 09, 2007 at 12:56:43PM +0100, Corinna Vinschen wrote:
> > Yet the latter works for me, whereas the former results in mmap()
> > failures for files smaller than the page size.
> 
> The latter works for you because it's wrong.  Since it uses 64K, mmap
> thinks it doesn't have to add filler pages.  So adding the filler pages
> can't go wrong.  So you can access your file, but you get the SEGV
> exaclty after the last 4K page of the file, not at the end of the
> expected 64K page.
> 
> 
> Corinna

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