Thanks paulbort!

SysInternals has a tool called "contig" that was close enough that with a little Perl, I could make it Do The Right Thing.

contig reports the number of fragments that comprise each file in a directory. It's normal output was surprisingly unreliable-- it skipped files apparently randomly sometimes-- but the verbose output seems to be more consistent. Also, it doesn't run continuously. In order to get a picture of fragmentation over time, the user has to run contig manually over and over.

So I wrote a little controller script in Perl that runs contig every 5 seconds in verbose/recursive/analyze mode, parses the output, and writes the interesting parts to an output file. Here's the script:

use warnings;
use strict;

open OUT, ">out.txt";

while (1) {
    $| = 1; 
    my @out = qx/contig.exe -a -s -v *"/;
    foreach my $line(@out) {
        if ($line =~ "is in") {
            print OUT $line; 
        }
    }
    sleep 5;
    print OUT "\n";
[download]

I was pleasantly surprised to find that @out actually contained what I wanted it to. Made parsing the output really easy.