Re: [dooglus@gmail.com: display problem after renaming open image files]

[Chong Yidong <cyd@stupidchicken.com>]

David Kastrup <dak@gnu.org> writes:

>>     This is because the underlying image file, pic1.png, is gone.  I think
>>     this is not worth fixing at this point.
>>
>> What causes this bug?  What data structure still refers
>> to the old file name, and has not been updated to the new one?
>
> The image property.  And Emacs does not track the arbitrary renaming
> of files outside of it.
>
> We can either let the image property refer to the file, or we can use
> a :data property.  The latter, however, would require duplicating the
> image content into that property, so we'll permanently have
>
> a) the image buffer with the content
> b) the :data property with the content
> c) the image cache with the content

Exactly.  This would be particularly annoying considering people now
routinely handle image sizes in the 10s or 100s of megabytes.

If you move the underlying file outside of Emacs, there's no way for
Emacs to know where you moved it; as far as it can tell, you might as
well have deleted it.

> the current state of affairs is _perfectly_ usable, reasonably
> understandable and consistent and fit for release.

1000% agreement.