Date   : Mon, 19 Dec 2011 20:09:48 -0600
From   : jules.richardson99@... (Jules Richardson)
Subject: ADFS directories - "reserved" bytes

I'm just decoding some Panos-related disk images at the moment... one 
'gotcha' that I found is that the following two references claim that byte 
0x4ff in a directory block should be 0x00:

http://mdfs.net/Docs/Comp/Disk/Format/ADFS
http://cowsarenotpurple.co.uk/bbccomputer/native/adfs.html

... however, I've got a disk here that has 0x14 in that location for one 
single directory on the disk (all other dirs have 0x00 at offset 0x4ff).

I just wanted to check that there's no significance there - the disk image 
is otherwise "good", i.e. free from corruption. I don't have a working 
emulator or hardware handy to check to see what ADFS itself does[1] in such 
a situation (although I did find an ADFS manual kicking around the 'net and 
it says nothing of what that particular byte should be set to - but then 
its technical section is rather light on the information front anyway :-)

[1] I did wonder if it's a quick little kludge for 'hiding' the contents of 
a directory...

I can tweak my access code to not check for 0 at that location of course - 
I'm just not sure if this 'problem' disk is a one-off (and I'd be better 
off changing that byte to 0 in the disk image file).

cheers

Jules