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Date: Fri, 5 Dec 2003 11:22:01 +0000 (GMT)
From: Anton Altaparmakov <aia21@cam.ac.uk>
To: Andy Isaacson <adi@hexapodia.org>
cc: Rob Landley <rob@landley.net>, linux-kernel@vger.kernel.org
Subject: Re: Is there a "make hole" (truncate in middle) syscall?
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On Thu, 4 Dec 2003, Andy Isaacson wrote:
> On Thu, Dec 04, 2003 at 02:32:23PM -0600, Rob Landley wrote:
> I'm curious -- does NTFS implement sparse files?  Does the Win32 API
> provide any way to manipulate them?  Does the NT kernel have any sparse
> file handling?

Yes it does.  The new NTFS Linux driver has full support for sparse files
as does Windows of course.

Windows does provide a function which is just "make hole".  It takes
starting offset and length (or was it ending offset instead of length,
can't remember) and makes this sparse (obviously aligning to cluster
boundaries, etc).

Best regards,

	Anton
-- 
Anton Altaparmakov <aia21 at cam.ac.uk> (replace at with @)
Unix Support, Computing Service, University of Cambridge, CB2 3QH, UK
Linux NTFS maintainer / IRC: #ntfs on irc.freenode.net
WWW: http://linux-ntfs.sf.net/ & http://www-stu.christs.cam.ac.uk/~aia21/