Re: NTFS block allocation policy (how does it work?)

From: George M. Garner Jr. (gmgarner_at_newsgroup.nospam)
Date: 02/26/05 

Date: Sat, 26 Feb 2005 02:48:33 -0500

Pat,

> If you know at least the approximate size of the file, the best thing to
> do would be to pre-allocate the file, then go back and write to it.<

Could you be more specific as to how to allocate the file. I see the
function SetFileValidData. But that assumes that you already have allocated
the file. Elsewhere I have read that one should not use SetFilePointer(Ex)
because of the added overhead of writing zeros to the file. Is there a way
to allocate the file without incurring the overhead of immediately zeroing
out the clusters. I know the pagefile does this but I do not see an api
that permits it.

Regards,

George.

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