Why QNetworkReply do not finished immediately sometimes while network is not connected

[Hanson]

I have code like this:

bool canConnectToInternet()
{
		QNetworkAccessManager netManager;
		QNetworkRequest m_request(Host);

		QNetworkReply* reply = netManager.get(m_request);

		QTimer timer;
		timer.setInterval(3000);
		timer.setSingleShot(true);
		QEventLoop loop;
		QObject::connect(&timer, &QTimer::timeout, &loop, &QEventLoop::quit);
		QObject::connect(reply, &QNetworkReply::finished, &loop, &QEventLoop::quit);
		timer.start();
		loop.exec();
		if (timer.isActive())
		{  // not time out
			timer.stop();
			if (reply->error() == reply->NoError)
			{
				return true;
			}
			qDebug() << "canConnectToInternet: " << reply->error();
		}
		else
		{
			qDebug() << "canConnectToInternet: timeout";
			QObject::disconnect(reply, &QNetworkReply::finished, &loop, &QEventLoop::quit);
		}
		return false;
}

My question is that when the net is connected it work well, and i cut the net when running the program, and it will cost 3 ms then print "canConnectToInternet: timeout".But when I restart the app it immediately return.

Thanks!

[VRonin]

@Hanson said in Why QNetworkReply do not finished immediately sometimes while network is not connected:

cost 3 ms

Ok, define the difference between "immediately" and 3ms.

[J.Hilk]

@VRonin thats your concern? And not the content of that function? 🙈

[Hanson]

@VRonin I wrote it wrong.--! It cost 3 seconds.