in reply to Inline::C and NULL pointers
Posts in the rest of this thread suggests you are not wedded to using Inline:C. If this is the case then it is worth having a look at FFI::Platypus.
A search of the FFI::Platypus::Type docs for "NULL pointer" gives a few examples that suggest undefs can be automatically mapped to NULLs.
There are also quite a few modules on CPAN that use FFI::Platypus for these sorts of bindings, so plenty of prior art that can be adapted.
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