I've got a perlxs module that maps a pointer to a C struct to a perl object. Here's the typemap: 
TYPEMAP
cstruct * T_OBJECT

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My question is, in my new() method, I would like to return undef on failure. What is the correct method for doing this? Does something like this work: 
cstruct *
new( field )
    int field;
  CODE:
    if( something_wrong() )
    {
        /*** is this correct below??? ***/
        RETVAL = (cstruct *)&PL_sv__undef;
    }
  OUTPUT:
    RETVAL

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Is the cast above the correct way? Or should I have my constructor return an SV* and then coerce my pointer into an IV? Thanks for the help.

In reply to perlxs new() returning undef by bmdhacks

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