Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!mnetor!seismo!lll-lcc!rutgers!husc6!husc4!may
From: may@husc4.HARVARD.EDU (may)
Newsgroups: comp.sys.amiga
Subject: AmigaDOS & DISKED
Message-ID: <1395@husc6.UUCP>
Date: Sun, 15-Mar-87 16:47:39 EST
Article-I.D.: husc6.1395
Posted: Sun Mar 15 16:47:39 1987
Date-Received: Mon, 16-Mar-87 04:19:47 EST
Sender: news@husc6.UUCP
Reply-To: may@husc4.UUCP (Jason May)
Distribution: world
Organization: Harvard University
Lines: 18

I've been playing with DISKED - yes, I know, dangerous - and I have some
questions about disk layout in AmigaDOS.  The material in the few pages
on it in the AmigaDOS manual put out by Bantam is very meagre.
How is the disk bitmap laid out?  The root block contains about 25 long
words giving the location of the disk blocks containing the bitmap, but
their is nothing in the manual saying how the bitmap is stored.  If
the format is one bit per disk block, with the condition of the bit
giving the allocated/unallocated condition of the block, then 1760 disk
blocks should only take up 55 long words.  Is this correct?  If so, then
which order are the blocks described in?  Does the condition of the first
bit show the condition of disk block 0, or disk block 1759, or something
else?  I'm trying to lock out permanently damaged sectors by putting them
all in a file, but I can't figure out how to tell the system that those
blocks have been allocated, and not to give them to another file.

				Thanks in advance,
					Jason May
may@husc4.harvard.edu		seismo!harvard!husc4!may