Path: utzoo!attcan!uunet!cbmvax!daveh
From: daveh@cbmvax.UUCP (Dave Haynie)
Newsgroups: comp.sys.amiga
Subject: Re: a gotcha with the FFS (no, my mistake)
Message-ID: <5234@cbmvax.UUCP>
Date: 14 Nov 88 19:34:38 GMT
References: <1072@esunix.UUCP>
Organization: Commodore Technology, West Chester, PA
Lines: 46

in article <1072@esunix.UUCP>, blgardne@esunix.UUCP (Blaine Gardner) says:

> DiskSalv really saved my hide here, thanks Dave! One possible tiny bug
> though. I was running the salvage from one 34M partition to a directory
> on my second 34M partition. After ~880K it told me that the disk was
> full, and to insert another. (This is with about 28M free on the
> destination partition.) I aborted the salvage, and retried with the
> NOCHECK option, and it worked fine.

What you've run into is one of those oddities I mentioned in my previous
posting.  DiskSalv does actually check the size of the output device.
When you're recovering a file, it checks the size of the file against the
size of the output device.  If the file won't fit, you get that DISK FULL
message, and you'll keep getting it until you give it a disk that'll fit
that file plus it's directory level.

This is all well and good, expect that I found, so far on FFS partitions
only, that the file size (I was using the file header entry that told
me how many blocks were in the file, as that's what DiskSalv cares 
about) on files is occasionally wrong.  Sometimes very wrong.  These
may just be deleted files, by they can really confuse DS V1.3.  I have
a new version almost ready for release that does the following:

	- Uses some redundancy information in a file header to try and
	  figure out the real size of the file.
	- Does bounds checking to reject impossible file sizes.
	- Checks extension block information to further back up it's
	  estimation of file size.
	- If all else fails, the DISK FULL message now tells you how
	  many blocks are free on the disk and how many it thinks the
	  file needs.  You have the option to skip that file or
	  ignore the warning as well as changing your output size.

> The docs say you need to use NOCHECK if RAM: is the destination (because
> of RAM:'s constant 0% free status). But shouldn't DiskSalv check to see
> how much space is REALLY there, instead of assuming 880K?

As I said, it really does.  NOCHECK is supposed to be set automatically
when RAM: is given as output, but that was also slightly damaged in V1.3,
and is now fixed.

> Blaine Gardner @ Evans & Sutherland    580 Arapeen Drive, SLC, Utah 84108
-- 
Dave Haynie  "The 32 Bit Guy"     Commodore-Amiga  "The Crew That Never Rests"
   {uunet|pyramid|rutgers}!cbmvax!daveh      PLINK: D-DAVE H     BIX: hazy
              Amiga -- It's not just a job, it's an obsession