Re: c-function returns multiple rows

Kirill Krasnosselov <kirill(at)digicol(dot)de> writes:
> PG_FUNCTION_INFO_V1(dc_ftx);
> Datum
> dc_ftx(PG_FUNCTION_ARGS)
> { ReturnSetInfo* rsi = (ReturnSetInfo *)fcinfo->resultinfo;
> rsi->isDone = ExprEndResult;
> PG_RETURN_NULL();
> }

This looks like it should work, but you're living dangerously
by not checking that you're being called the way you expect.
You should have something like

if (!fcinfo->resultinfo || !IsA(fcinfo->resultinfo,ReturnSetInfo))
elog(ERROR, ...);

in there before trying to dereference the pointer.

> In my opinion this function call shall returns a empty table,
> but this call does not end.

Try attaching to the backend with a debugger to see what it's doing.

regards, tom lane