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Blah64 · 12:15 AM

Hi all,

I have a G4 iMac sitting absolutely idle while I try to figure this out. Hopefully someone can give a hand!

After quite a bit of searching and some over-the-phone testing, it appears that there is (was?) a repeatable bug in Jaguar (System 10.2) related to Finder temporary disc images. Try the following (it won't mess anything up):

1) Insert a blank CD-R
2) Let the Finder create a temporary disc image, ready to use for burning. Create a new folder on that disc image.
3) Open the Terminal, move to the folder on that new volume and do 'ls' just to take a look. The volume is now busy. Alternatively, if you're not comfortable in the Terminal app, you may be able to just put any little text document in that folder and open in TextEdit. The goal is simply a busy volume that you should not be able to eject.
4) Go back to the desktop and eject that volume by dragging to the Burn icon, but when the dialog comes up asking if you really want to burn, press Eject.
5) You'll be left with a sort of rogue disc image on the desktop that you can *apparently* use.

The big problem comes if this happens without your knowledge, or perhaps there's another way that a temporary Finder disc image can be left in this rogue state. Now you spend how ever many minutes, hours or days [yes, days :-( ] loading up data on this disc image. When you finally drag it to be burned it just disappears!! Along with any un-backed up data you might have on the image.

My questions are:

1) Is this a known Jaguar bug? I had a friend replicate on a remote computer, so unless we're misunderstanding it, it looks repeatable.
2) Where are the temporary disc images the Finder creates stored? This may be a question that only Apple can answer, but might be useful.
3) Most importantly, how can one resurrect one of these disc images. As one might gather from the above, I have a dire need to recover data from an image the Finder created for a CD-R, which has now "disappeared". Is this something one of the disk utilities like DiskWarrior, Norton, etc. could solve? i.e. Does the Finder really create just a standard image file that can get dismounted/deleted/disassociated from the file system?

If anyone has a Jaguar system with a CD-R and any kind of file-recovery software I would be extremely grateful if you could try the above, copying some files onto the fake disc image, then try to eject/burn the image (it should just disappear from the desktop). Then the most important part for me, if there's any easy way to recover that disc image I'll be *more* than happy to pop out to the store immediately to buy whichever disk utility sofware makes it possible! In the meantime I'm not even touching or shutting down the computer!

Thanks so much, I hope all this makes sense.
- MB

Blah64 · Jun 8, 2004, 12:26 AM

This is more serious and widespread than I thought.... Even though it's somewhat better in Panther, you can still end up with an inconsistent file system.

In Panther, running through a similar process as above, using a Terminal window to navigate to a folder on the temporary disc image (to keep the volume busy) still results in a rogue disc image. One that you can use to your heart's content until it comes time to burn it and then it just disappears.

However, in Panther if you hold the volume busy by opening a document on that volume in another application, like TextEdit, ejecting the temporary disc image also removes its icon from the desktop and you can't continue to use it. But, you'll still be left with an open document that has been disassociated with its file, since the volume is now gone. Better, but still wrong. The disc image should not be dismountable if it's busy.

Bottom line question:
How can I recover my temporary disc image???? The data is obviously sitting on
the hard drive.

Any ideas? Thanks.