Yeah ... That's the same solution as Corion suggested above. Just not as an extra indirection in the Perl layer, but at the C layer.

So now there's 3 solutions. All of them keeping a reference to the "owning" C object.
  1. Make the objects plain C pointers and keep the reference in the NV slot
  2. Make the objects an extra C indirection struct and keep the reference in that
  3. Make the objects ordinary Perl blessed hashrefs and keep a reference in there to the "parent" perl object ... when will then not have it's DESTROY called before the child is gone.

I think all of them will work, but I still wonder what Perl actually guarantees about dualvalue SVs. Since its practicaly encouraged by Scarlar::Util, I would have expected such a statement in perlapi or perlguts.

To put it further into perspective. Here's Devel::Peek description of the T_PTROBJ typemap SV.. As it clearly shows, the PV and NV slots are empty (as standard). But what happens if you use them?

In reply to Re^4: Managing C library memory in XS by petermogensen
in thread Managing C library memory in XS by petermogensen

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