Yes, I think it's because in the line: 
    setCallback( \&calledBack );

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the reference to the subroutine is being assigned to a temporary SV, which then goes out of scope (since it doesn't know the C program is still using it).   Then when C tries to use it, the thing it was pointing to is no longer there.

So if you try this instead: 

    my $psub = \&calledBack;
    setCallback( $psub );

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you should get the results you want, as the subroutine reference now exists in the still persistent, lexically-scoped "$psub" to which the SV "g_callback" points.

It's a really good question.

In reply to Re: Inline::C callbacks to Perl by liverpole
in thread Inline::C callbacks to Perl by BrowserUk

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