In general C programming, one doesn't have optional arguments. And generally, being able to give a pointer value that is clearly not intended as valid (a NULL) is a valuable thing. That maps very nicely for a Perl interface, to turning an undef input (or, conceivably, no input at all) into a NULL in C terms.

tl;dr: C and Perl have different idioms, and while XS should probably take an SV* and treat it idiomatically, actual C has different needs.

In reply to Re^10: Inline::C and NULL pointers by etj
in thread Inline::C and NULL pointers by markong

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