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From: lphillips@lpami.wimsey.bc.ca (Larry Phillips)
Newsgroups: comp.sys.amiga
Subject: Re: FFS on Floppies in 2.0
Message-ID: <1785@lpami.wimsey.bc.ca>
Date: 15 Jul 90 22:49:30 GMT
Lines: 29
Return-Path: <lpami!lphillips>
To: van-bc!rnews

In <24729@estelle.udel.EDU>, new@udel.EDU (Darren New) writes:
>>>To format an FFS floppy under 2.0:
>
>Speaking of which:
>Has 2.0 changed the layout of FFS or OFS partitions enough to
>mess up software like disk optimizers?  I have a backup
>program I've written that relies on some of the (as of 1.2)
>undocumented disk structure like directory header block
>formats and such.  Other than questions of initial placements,
>will this still work under FFS2.0?    -- Darren

There is one new kind of header block, the link. You will have to take that
into account. The primary type (longword $02) is $00000002, the secondary type
(longword $7F) if $FFFFFFFC, and the link is stored in longword $75. The real
directory header has what looks like a link count in longword $75.
This info is for hard links; no idea what a soft link will look like.

If you are depending too heavily on things undocumented, you could get into
difficulty. Best way I found was to use the FIB for all information.

-larry

--
The raytracer of justice recurses slowly, but it renders exceedingly fine.
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|   //   Larry Phillips                                                 |
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