david, at 16:37 on May 19 1996, you wrote to Bill Grimsley...

BG> Ever run CHKDSK /F:3 on your HPFS drives?  It's absolutely fucking amazing 
BG> what level 3 can recover.

db> If I remember correctly, Doug A. (the chief guy in IBM working on HPFS) 
db> said in Usenet last year that level 3 is a "flying blind"
mode when all 
db> else fails;  that is, use it if you have nothing to lose, but it's 
db> *remotely* *possible* that level could actually *cause* problems rather 
db> than *fix* them, depending on the state of your file system.

Dunno, I ran it once, just after an HPFS defrag, and it actually found and
recovered a couple of files which I'd intentionally deleted ages ago.  At
the time, I was rather impressed, but didn't know it could be harmful as
well.

db> Level 2 is s'posed to be the highest you use for "normal
emergencies".

Yep.  And so say the docs.

PE>> Is there specs around for HPFS?

BG> The IBM Redbooks would be the logical choice here.

db> It's not there 

Oh dear, that's rather unfortunate.

db> IBM is (was?) not allowed to release HPFS specs because it was actually 
db> *Microsoft* (Gordon Letwin) who actually developed it in the first place.  

Of course, right back in the good old days before MS decided to start
making crappy GUIs on their own.  :)

db> People have been discovering bits and pieces here and there, and putting 
db> the information together *outside* IBM in order to effectively reverse 
db> engineer HPFS.  Few people (like the GammaTech bloke) have actually been 
db> *given* HPFS specs for writing OS/2 software since the MS/IBM split.

Which is why the Gammatech Utes work so well, presumably.  It does take
quite a while when defragging to just one extent though.  :)

db> Chris Graham would be my vote for the most knowledgeable guy in Australia 
db> when it comes to HPFS (doesn't even work for IBM *or* Microsoft).

Of the Graham Utilities, I presume?  Incidentally, I was under the
impression that MS's NTFS was very similar to HPFS.  Comments?

Regards, Bill

--- Msgedsq/2 3.20