Writing C Modules with Inline::C

    // loop over key/value pairs

    for (i = 1; i <= count; i++) {

      value = hv_iternextsv(hv, &key, &len);

      // push key and value

      Inline_Stack_Push(sv_2mortal(newSVpvn(key, len)));

      Inline_Stack_Push(sv_mortalcopy(value));

    }

    // done pusing on the stack

    Inline_Stack_Done;

    // free hv explicitly

    SvREFCNT_dec((SV *)hv);

    // return two SVs for each key in the hash

    Inline_Stack_Return(count * 2);

  }

  // G_SCALAR or G_VOID context   return a reference to the new hash

  Inline_Stack_Reset;

  Inline_Stack_Push(sv_2mortal(newRV_noinc((SV *)hv)));

  Inline_Stack_Done;

  Inline_Stack_Return(1);

}

This function returns a hash reference in scalar context and a list of key value 

pairs in list context:

# scalar context

$type_data = Gnome::MIME::type_data("text/html");

$program = $type_data >{open};

# list context

%type_data = Gnome::MIME::type_data("text/html");

$program = $type_data{open};

The code used is substantially similar to the XS version, and again the difference is 

largely a matter of the Inline::C macros used.

To start, the function begins with a void return type, which works similarly to a 

PPCODE block in XS in that it allows you to handle the return stack explicitly:

void type_data(gchar *type) {

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