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From: alexis@reed.UUCP (Alexis Dimitriadis)
Newsgroups: net.micro.mac
Subject: Re: A Disk Recovery Tale
Message-ID: <2177@reed.UUCP>
Date: Thu, 21-Nov-85 04:48:24 EST
Article-I.D.: reed.2177
Posted: Thu Nov 21 04:48:24 1985
Date-Received: Sat, 23-Nov-85 05:14:42 EST
References: <8511161155.AA10811@kim>
Reply-To: alexis@reed.UUCP (Alexis Dimitriadis)
Organization: Reed College, Portland, Oregon
Lines: 41
Summary: 

> After spending hours laboring over the disk "foobar" I was alarmed and
> dismayed to see the "Do you want to initialize?" dialog box.  
> [...] Somehow, miraculously,
> the directory blocks on my "trashed" disk were fixed as they were copied
> to the new disk.  They couldn't be read by fedit nor by the Mac's disk insert
> handler, but they could be copied.  How can this be?  You tell me.

  I've often had to play doctor (and sometimes mortician :-() to 
people's disks.  A couple of tricks that worked:

  If you are getting I/O errors when reading a file or a disk,
sometimes it helps to enter FEDIT and try reading through the file
blocks.  When you reach the block that gives the I/O error, read the
adjacent blocks, touch them (e.g., by changing a character to itself),
and write them back out.  Then try reading the bad block again.  If
you are lucky, you won't get an I/O error (you may get garbage on the
block, but you have the rest of the file).  This worked on a disk that
someone had sat on.

  Some versions of Macwrite will periodically create files that they
can not read afterwards.  The best thing to do is get rid of all
copies of the buggy version, but such a file may be read by setting
its mode to TEXT.  There will be garbage where rulers and font changes
used to be, and you'll have to put those back in manually, but at
least Macwrite can read the file.  (And then once I had to dump a file
to the imagewriter using Fedit, screen by screen, so it could be typed
in again.  Sigh..)

Disclaimer:
  I know very little about the guts of the Macintosh.  If someone has
informed instructions for the restoration of bad disks, could you step
forth?  It seems our disks have been dropping like flies around here.

Alexis Dimitriadis
-- 
_______________________________________________
  As soon as I get a full time job, the opinions expressed above
will attach themselves to my employer, who will never be rid of
them again.
				alexis @ reed
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