Assuming you are at at least Windows 2000, SysInternals has a sample defrag with API explanation at their site.

They tend to have lots of good low-level Win32 hacking tools.

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Spring: Forces, Coiled Again!

In reply to Re: measure Win32 disk fragmentation with Perl? by paulbort
in thread measure Win32 disk fragmentation with Perl? by McMahon

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