QTimer with asio::io_service.poll_one() or poll() - c++

Question

I am using asio (standalone header only) within a Qt Quick application.
As Qt and asio have both their own event loop if I understood correctly, I use a QTimer signal to call the class that holds my asio::io_service object.
QTimer *timer_io = new QTimer();
QObject::connect(timer_io, SIGNAL(timeout()), &my_INandOUT, SLOT(poll_ios()));
timer_io->start(IO_TIMER);
I have set IO_TIMER to 100 ms. I have read in the documentation that asio::io_service.reset() must be called after each poll(). So the slot poll_ios() has the following code:
void INandOUT::poll_ios()
{
// qDebug() << "poll_io signal";
m_io_service.poll_one();
m_io_service.reset();
}
Is that the correct way to call the reset() ? Or should I call it in each handler once they have finished their task ? Is it safe or could I loose asio events ?

Answer 1

It would be simpler and easier to lose the asio events and use Qt builtin classes instead: e.g: QNetworkAccessManager or QUdpSocket.
However, calling poll_one or poll from a timer (as you have done) is the normal way of using asio with an external event loop.
But I don't recommend calling reset after calling poll_one since according to the documentation it should only be called:
when a previous invocation of these functions returned due to the
io_service being stopped or running out of work
If you re-enable your asio handlers (e.g. enabling a receive handler after receiving a message) then io_service always has work to do. In which case it would be better to just call poll instead of poll_one and lose the call to reset, e.g.:
void INandOUT::poll_ios()
{
// qDebug() << "poll io signal";
m_io_service.poll();
}