I don't know what the failure mode was on Windows (file system full? something else?). Regardless of the underlying failure, if you write the image file and the write does not successfully complete, then you almost certainly have a junk file that cannot be fixed.
But to your other question, could we check for the failure and not exit the image, that's definitely worth looking into.
Take a look at SmalltalkImage>>snapshotEmbeddedPrimitive and SmalltalkImage>>snapshotPrimitive. If the method comments are right, then a nil result would indicate a write faiure. I don't know if the actual primitives in the VM behave this way (if not they could be fixed). But if that is how the primitives behave, then it should be possible to add a check for nil to prevent exiting the image after a failed write.
I do not see any such check in SmalltalkImage>>snapshot:andQuit:withExitCode:embedded: so it would be worth looking at this to see if a nil check could be added to protect against the kind of failure you saw.
Dave
On Fri, Sep 03, 2021 at 10:04:18PM +0000, Thiede, Christoph wrote:
Truncate? It has still a very usual file size ... But when I try to open it, the VM asks me for another image file, so apparently, it cannot read it. No idea what's going on here ...
Best,
Christoph
Von: Squeak-dev squeak-dev-bounces@lists.squeakfoundation.org im Auftrag von David T. Lewis lewis@mail.msen.com Gesendet: Samstag, 4. September 2021 00:01:54 An: The general-purpose Squeak developers list Betreff: Re: [squeak-dev] Image damaged due to IO error while saving
On Fri, Sep 03, 2021 at 09:02:07PM +0000, Thiede, Christoph wrote:
Or is there maybe, just maybe some kind of automatic image repair tool? One that does not require in-depth knowledge of the file format internals of .image files? :-)
No, if you truncate the image file, it's junk.
Dave