Some senseless babbling from Darin Mcbride to Mike Ruskai
on 10-22-99  08:17 about HPFS freespace bmp list...

 MR> What I'd like to do now is distribute the program that does this
 MR> comparison, to get a wider range of data.  Maybe HPFS386 doesn't have
this
 MR> problem, or a different version of HPFS, etc.
 
 MR> The problem is that I'm not certain how to handle drives larger than 4GB.
 MR> The freespace bitmap list is four sectors long, which allows for 512 data
 MR> bands (about 4GB).  Also in the HPFS SuperBlock is a pointer to a spare
 MR> freespace bitmap list.  What's not there is the length of this spare
list.
 MR> If it's only four sectors, like the primary list, then HPFS dies at 8GB,
 MR> without another list.
 
 MR> Unfortunately, I don't have any HPFS partitions larger than 4GB that I
can
 MR> poke around on.

 DM> Send me the source (dmcbride@tower.to.org), and I'll send you back its
 DM> output on my 7.99 GB HPFS drive. (8189MB)

 DM> The reason I ask for source is so I can convince myself you're not
 DM> going to damage my harddrive.  ;-)  Also, I assume you're using VAC 3.0
 DM> or gcc (EMX 0.9d) to compile it.

I wouldn't dream of distributing a "low-level" hard drive program without
source ;)

As it turns out, I found out what should make it work on drives of any
size.  You can download the program at:

http://home.att.net/~thanny/fspace.zip

That includes the source code, and a VACPP 3.08-compiled executable.

The output should look like this (from my 3GB drive):

Reported free sectors: 2956682

Actual free sectors: 2960778

Free sector discrepancy: 4096

Reported free space: 1513821184

Actual free space: 1515918336

Free space discrepancy: 2097152

I haven't done any work towards figuring out where those free but
unreachable sectors are.  I might do that when I'm done writing this, since
I have an empty partition to fill up just for the purpose :)

Mike Ruskai
thannymeister@yahoo.com


... Bones, examine the yeast creature. He's bread, Jim.

___ Blue Wave/QWK v2.20
--- Platinum Xpress/Win/Wildcat5! v3.0pr2