And the problem is that I can't see when I get a "person" pointer I get back in DESTROY whether I'm allowed to free it.

This is the key paragraph and decision point in the code. You should wrap the real free_person() in XS function that would have the logic like this: 

    if (person_refcnt(person) == 0)
        free_person(person);
    else
        ; /* Do nothing: free_record() will free the person as well */

[download]
Then from Perl just call this wrapper and let the lower-level logic worry about it.

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

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