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Python Function pointer in C

Nick Coghlan ncoghlan at email.com
Thu Nov 25 09:10:24 EST 2004 
David Gilbert wrote:
> I'm trying to maintain the interface to KQueue for FreeBSD.  At one
> point, the C module stores an opaque object in a C structure such that
> the opaque pointer can be used later by the application.

In this case, a Py_IncRef/DecRef pair is definitely required - the 'borrowed' 
reference from the Python function call only lasts until the function returns. 
You need your own reference if you're going to hang on to the pointer.

> How do I define "udata" such that I can stuff the lambda reference in
> there?

PyObject* should be fine so long as the references are handled correctly.

> Now... I've wondered if this is a reference counting issue --- but
> this still happens when I use the name of a module global function as
> udata.

I'd suggest adding the IncRef/DecRef pair and trying it out again. I can't see 
anything else obviously wrong in the fragments you've posted.

If that was the sole problem though, I would have expected the same as you - for 
the module global function to work correctly.

Sorry I can't be more help. . .

Cheers,
Nick.
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