Asynchronous Query processing

I have a need to do asynchronous query processing. I am a little confused
by the order and frequency of calls. Can someone tell me if the below is
correct? The code comments are littered with my questions.

PQsendQueryParams(pgconn, "SELECT ..", ....);

while(1)
{
epoll/poll/select PQsocket(pgconn) [read]

// call this each time poll indicates data is ready?
PQconsumeInput(pgconn);

// If isBusy returns 1, just poll again? Will this indicate 0 when I have
a full PGResult set?
// Or, can it split the results of a single statement across multiple
result sets.
if(PQisBusy())
conitnue;

// I know the docs say keep calling getResult until it returns NULL. In
my
// case, I am wondering if that is needed. I only send one statement at a
// time to the server. The connection is not listening for notifies
either. Do
// I still need to call getResult multiple times? I saw many examples
online
// that DO NOT call it multiple times, all of them executed a single
statement.
res = PQgetResult(pgconn);

process_results(res);
}

thanks, brendon