Re: PG_FREE_IF_COPY()

Tom Lane [mailto:tgl(at)sss(dot)pgh(dot)pa(dot)us] wrote:
> "John Hansen" <john(at)geeknet(dot)com(dot)au> writes:
> > Given the following snippet:
> > HeapTupleHeader tuple;
> > Datum temp;
> > bool isnull;
>
> > tuple = PG_GETARG_HEAPTUPLEHEADER(0);
> > temp = GetAttributeByName(tuple, "data", &isnull);
>
> > When using this for a btree operator functions, you need to
> > PG_FREE_IF_COPY(?,?);
>
> > Which of the above parameters need I free?
>
> It'd probably be wise to do a FREE_IF_COPY on the tuple.
>
> GetAttributeByName, however, hasn't copied anything (if it's
> a pass-by-ref type you'll just get a pointer into the tuple).
> If you do a copy further down that might be a reason to free
> something, but this code alone isn't making a copy.

Cool, thanks...

>
> regards, tom lane
>
>

... John