Subject: Re: hexdumping large sparce files
To: David Laight <david@l8s.co.uk>
From: Ignatios Souvatzis <ignatios@theory.cs.uni-bonn.de>
List: tech-kern
Date: 01/27/2003 12:06:14
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Hi,

On Sat, Jan 25, 2003 at 08:41:33AM +0000, David Laight wrote:

> There could be something done with ioctl/fcntl a bit like the way of
> making a file sparse (I can't remember the command off hand).

You do that by never writing to the hole, but lseek()ing to the next part
you want to write.

Hm, which makes me think, that maybe we want SEEK_HOLE, which will be
equivalent to SEEK_CUR if the filesystem doesn't know about holes, and=20
relative to the end of the next hole otherwise.

Regards,
	-is

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