PROBLEM SOLVED, THANK YOU.
I renamed the new _/Squeak.exe/_ to /_Squeak Cog Spur Virtual 
Machine.ex_e/. I can then use the Windows operation /_openWith_.../ to 
select the appropriate VM for old and new images.

Many thanks for your helpful responses.
--Trygve

On 05-Apr-20 4:43 PM, Eliot Miranda wrote:
> Hi Trygve,
>
>> On Apr 5, 2020, at 2:47 AM, Trygve Reenskaug <trygver at ifi.uio.no> wrote:
>>
>>  I'm struggling with a new .image3 extension. It seems that /Squeak 
>> Cog Spur Virtual Machine /actually *KNOWS *that all images have the 
>> *.image* extension. This seems to mean that I can't run two different 
>> Squeak generation images within the same OS instance.
>
> there’s no restriction on running multiple kinds of image or multiple 
> images or multiple instances of the same image.  One can always drop 
> an image on the right vm, or manually launch a specific vm with a 
> specific in a shell.
>
> The issue is only having double clicking select an appropriate vm for 
> the image, and for that you’re right that one needs a wrapper.
>
> Pharo has a wrapper implemented in Smalltalk, PharoLauncher, that 
> could be adapted.  VisualWorks has a small wrapper and an ini file, 
> VisualWorks.exe & VisualWorks.ini IIRC (know it? I wrote it).
>
> It wouldn’t be hard to implement the wrapper solution.  I’ll try and 
> get that done in the next few days.  But then it has to get pushed 
> through to production, to be built using some kind of CI.  And of 
> course it makes sense on all platforms.
>
>>
>> I'll try running my 3.10.2 under /Cog Spur Virtual Machine/. I hope 
>> it works.
>
> It won’t.  Spur 32-bit VMs are the only VMs that can run 32-bit Spur 
> images, Spur 64-bit VMs are the only VMs that can run 64-bit Spur 
> images, etc.  it isn’t just a matter of converting each individual 
> object.  There are bytecode set, closure design, identity hash and 
> object enumeration method, and other Smalltalk-level differences that 
> mean automatically converting images is impossible.
>
> Converting between 32-bit and 64-bit Spur images *is* automatable and 
> there is a program (a Spur image) I should package up to do it.  But 
> it takes a few seconds and requires VMMaker, so it is not small, and 
> so is not something to add the the vm and have some images takes 
> seconds to launch instead of milliseconds.
>
>>
>>
>> On 04-Apr-20 9:13 PM, tim Rowledge wrote:
>>> We were discussing this with regard to the 5.3 release but didn't have time to sort out. Having a wrapper that checks the image file format and picks the right vm is not in principle difficult; we just need someone to write it.
>>>
>>> The unix package for example already has a shell script that does a fair bit of fiddle-faddle. Adding use of the image format command wouldn't make a lot of difference.
>>>
>>> tim
>>> --
>>> tim Rowledge;tim at rowledge.org;http://www.rowledge.org/tim
>>> "Virtual Memory" means never knowing where your next byte is coming from.
>>>
>>>
>>>
>>>
>>>
>>
>> -- 
>>
>> /The essence of object orientation is that objects collaborateto 
>> achieve a goal. /
>> Trygve Reenskaug mailto: trygver at ifi.uio.no 
>> <mailto:%20trygver at ifi.uio.no>
>> Morgedalsvn. 5A http://folk.uio.no/trygver/
>> N-0378 Oslo http://fullOO.info
>> Norway                     Tel: (+47) 22 49 57 27
>>
>>
>

-- 

/The essence of object orientation is that objects collaborateto achieve 
a goal. /
Trygve Reenskaug mailto: trygver at ifi.uio.no <mailto:%20trygver at ifi.uio.no>
Morgedalsvn. 5A http://folk.uio.no/trygver/
N-0378 Oslo http://fullOO.info
Norway                     Tel: (+47) 468 58 625

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.squeakfoundation.org/pipermail/squeak-dev/attachments/20200407/7d7b9143/attachment.html>