Re: DSK image quirk

[mjmahon@aol.com (Michael J. Mahon)]

Rubywand wrote:

>Bill Garber writes ...
>> 
>> Here's one for the FAQs.
>> 
>> I tried to open a DSK image with CiderPress, and
>> it reported that it was not a valid DSK image, but
>> gave no reason otherwise. Then I tried with FishWings,
>> and that reported the same but told me that the size
>> was 143,361 instead of the required 143,360, so using
>> a hex editor I went in and removed one redundant byte
>> from the very end of the file and VOILA!, everything
>> can now see the image as a normal DSK image. Weird.
>> How do you suppose it got an extra byte? It was zipped.
>> Is it possible that the program used to compress it added
>> the extra byte to alleviate a fractional number of bytes in
>> compressed version? Hmmmm, weird.
>> 
> ....
>
>     Odd-sized .dsk disk images do crop up from time to time.
>They always seem to be a little larger than the correct size

Yes, they do.  Sometimes there is some garbage on the end
of the image, and sometimes there is a header or header
remnant prefixed to the image.

It would be handy ;-) if some of these _very_ useful disk image
utilities provided a "loose checking" mode that allowed the user
to correct these problems, either automatically or interactively.

-michael

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