Python 2 to Python 3 .so library incompatibility - need help

[Chris Angelico]

On Thu, Dec 17, 2020 at 6:06 AM Chris Green <cl at isbd.net> wrote:
>
> Some time ago (in July) I asked some questions here
> about problems migrating some code from Python 2 to Python 3.
>
> The specific problem that finally prevented me from managing to get it
> to work was a (Linux) .so file that had been built for Python 2 and,
> as I don't have the source, I can't build for Python 3.
>
> I need to have another go at fixing this as otherwise the code that I
> need to manage my printer will stop working as I update my Ubuntu
> systems.
>
> The specific error I'm getting is as follows:-
>
>     File "/usr/libexec/okimfputl.new/guicom.py", line 66, in <module> import pyscand
>     ImportError: /usr/libexec/okimfpdrv/pyscand.so: undefined symbol: _Py_ZeroStruct
>
> I know this is because the extension module is compiled for Python 2
> and _Py_ZeroStruct is only available in Python 2.  I don't have the C
> code for the module.
>
> Is there *any* other way around this, like a 'compatibility module' to
> use Python 2 .so files in Python 3 or anything like it?  I have all
> the Python code and have (up to hitting this problem) converted it to
> Python 3.
>

Basically no. The error you're seeing is a nice noisy one, but even if
you got past that, there'll be a LOT of incompatibilities.
Unfortunately, a quick google search for 'pyscand' showed up....
places where you've asked this question, suggesting that nobody else
uses this library. It looks like you're going to have to take a big
step back and figure out what the library is doing for you, and
reimplement that somehow. :(

Good luck.

ChrisA