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Date: Fri, 16 Jan 2009 17:41:09 +0100
From: Corinna Vinschen <corinna-cygwin AT cygwin DOT com>
To: cygwin AT cygwin DOT com
Subject: Re: how to get mmap page size?
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On Jan 16 15:10, Jay Foad wrote:
> Corinna Vinschen wrote:
> 
> > mmap always allocates in 64K chunks.
> 
> That doesn't seem to be true in practice. In the test below I mmap a
> 1080K file (this is a multiple of 4K but not a multiple of 64K). The
> first byte after the end of the file isn't readable.

Right.  The reason is that mmap started to map memory top down at one
point to fix a problem with Windows Vista.  The mechanism to align
the map always to 64K is still in Cygwin, but it currently doesn't
work for files.  I'll have a look into fixing that for Cygwin 1.7.


Corinna

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Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Project Co-Leader          cygwin AT cygwin DOT com
Red Hat

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