[Vm-dev] [Pharo-users] VM/Image magic numbers (Re: Pharo 6 snap install)

[Luke Gorrie]

On 15 April 2017 at 01:22, Ben Coman <btc at openinworld.com> wrote:

> The "magic decode for image files" seems related and possibly *very*
> useful....
> http://forum.world.st/magic-decode-for-image-files-td4941712.html#a4941837
>
> Now traditionally the VM has been backward compatible with old Images,
> but Pharo doesn't necessarily adhere to that and policy IIUC is
> release specific VM/Image pairs.
> So does Pharo require extra magic numbers to co-ordinate this?
> And how would this interact with OpenSmalltalk policy on these magic
> numbers?
>

I would really like a copy of the script that checks the magic number and
starts the right VM. David, could you share yours please?

I started writing

case file -m @share@/magic "$image" in
    'Smalltalk image V3 32b*')
        vm=@pharo-vm-cog@
        ;;
    'Smalltalk image Spur 32b*')
        vm=@pharo-vm-spur@
        ;;
    'Smalltalk image Spur 64b*')
        vm=@pharo-vm-spur64@
        ;;
    *)
        echo unrecognized image file format
        ;;
esac


... but would prefer to avoid reinventing the wheel e.g. on how to find the
image name in amongst the various options passed to $@.

I would quite like for my package to be able to open the pharo-launcher
image and the various images that this downloads. This means supporting
pre-spur images. I would ideally like to do that by building a non-spur
version of the latest VM, but I am not sure if that is supported for pharo,
there is no mvm script for non-spur. The alternative would be to just build
an old VM release with cmake.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.squeakfoundation.org/pipermail/vm-dev/attachments/20170418/1cd8d546/attachment.html>