Conference hydra::amiga_v1

2822.0. "DiskSalv and recovering deleted files" by WJG::GUINEAU (Opening the doors of Perception) Thu Aug 10 1989 10:02

Here's a bit from Dave Hayne on USENET about getting deleted files back.

Article 37593 of comp.sys.amiga
Path: shlump.nac.dec.com!decwrl!henry.jpl.nasa.gov!elroy.jpl.nasa.gov!usc!cs.utexas.edu!uunet!cbmvax!daveh
From: [email protected] (Dave Haynie)
Newsgroups: comp.sys.amiga
Subject: Re: fun and games with Disksalv
Message-ID: <[email protected]>
Date: 9 Aug 89 16:09:13 GMT
References: <[email protected]>
Organization: Commodore Technology, West Chester, PA
Lines: 54

in article <[email protected]>, [email protected] (Mike Smithwick) says:
> Keywords: Starship Enterprises

> Hey guys, I just discovered a neat trick with disksalv! Using disksalv
> you can un-delete files you accidentally hosed. Say you just downloaded
> 3 mb of animations from the WhizBangBBS. You go to your disk and see all
> of those .info thingies that the Download! program leaves scattered about.

> So you decide to dump them and type "delete #? .info" or something
> equally stupid. Your jaw hits the floor, and you wake the neighbors dog
> with a noise that sounds like an Altarian Megadonkey in heat. 

You can take it a little further than that.  Assuming that you deleted these
WhizBangBBS files from your system hard disk, you can avoid a bit of pain, and
endless system requesters of the "Please Insert SYSTEM: in FH0:" ilk by 
specifying the NODOS option on the DiskSalv command line.   Normally, when 
DiskSalv recovers from an input disk, it will inhibit DOS on that disk, which 
is not only The Proper Thing To Do from the point of view of the OS, but it 
should also prevent a badly damaged disk from crashing the system.  However,
for undeleting purposes, you know the disk isn't bad, and additionally, if you
inhibit your main system disk, other processes that count on it being there
will be unhappy.  So NODOS prevents the inhibit.

The next bit that helps in recovering specific files is the FILE option.  If
You could specify something like:

	DiskSalv fh0: ram: nodos file (Banzo|Iggy|Peps)Anim#? 

which will direct DiskSalv to only scan for the file that match the wildcard
specification shown, which would probably get back that three meg of Anim stuff
you just deleted.

One final hint is to limit the extent of the scan.  If I want to scan the whole
81 megs of my hard drive here, I can, but it'll take an awful long time.  
Chances are the file headers I'm after are somewhere near the middle of the 
disk.  So I can specify:

	DiskSalv fh0: ram: nodos file (Banzo|Iggy|Peps)Anim#? start 40% stop 60%

to scan the middle of the disk.  If that doesn't find everything, I might go
from 60% to 80% or 20% to 40% or somesuch, taking a fraction of the time it
would require to scan the whole disk.  

All these hints apply to DiskSalv V1.40 and later; the FILE option wasn't in any
earlier release, and the START/STOP options only accepted absolute block 
numbers, not the more natural percentages, in earlier releases.

>           *** mike (still looking for a publisher) smithwick ***

> "Los Angeles : Where neon goes to die"
-- 
Dave Haynie Commodore-Amiga (Systems Engineering) "The Crew That Never Rests"
   {uunet|pyramid|rutgers}!cbmvax!daveh      PLINK: D-DAVE H     BIX: hazy
           Be careful what you wish for -- you just might get it