Thanks to those who answered my question about the headers. I have
two new ones:
Do I need an OUTPUT section in a case where I'm altering an SV*
instead of a typemapped value? For example:
void
twice(a)
SV *a
CODE:
sv_setiv(a, 2 * SvIV(a));
OUTPUT:
a
That works with and without the OUTPUT section.
$number = 24;
twice($number);
print $number;
48
Second question: when I use the SvIV function to extract the integer
value from a scalar, I don't get the same behaviour Perl seems to
exhibit. When I turn "24 dogs" into an integer, I get 0 (and a
warning about "argument isn't numeric"). If I try that in Perl (for
example, with addition) I get 24. What am I missing?
$string = "24 dogs";
twice($string);
print $string;
0
Thanks,
Nat
