Testing link-local multicast in Qt

test.pro

#####################################################################
# Automatically generated by qmake (3.0) Sa. Sep. 6 01:08:04 2014
######################################################################

CONFIG += console
QT += network
TEMPLATE = app
TARGET = test
INCLUDEPATH += .

# replace filename or rename ...
SOURCES += test.cpp

test_complex.cpp

#include <QUdpSocket>
#include <QNetworkInterface>
#include <QThread>

int main(int argc, char *args[]) {
  // iterates over the interfaces and sends on each
	while(true) {
		QUdpSocket udp;
		QByteArray data("hello world");

		foreach(const QHostAddress& address, QNetworkInterface::allAddresses()) {
			udp.bind(address, 0);

			qDebug() << address;

			if(address.protocol() == QAbstractSocket::IPv6Protocol) {
				udp.writeDatagram(data, QHostAddress("FF02::1"), 4321);
			} else if(address.protocol() == QAbstractSocket::IPv4Protocol) {
				udp.writeDatagram(data, QHostAddress::Broadcast, 4321);
			}

			udp.close();
		}

		QThread::sleep(5);
	}

	return 0;
}

test_simple.cpp

#include <QUdpSocket>
#include <QThread>

int main(int argc, char *args[]) {
  // simple test
	while(true) {
		QUdpSocket udp;
		qDebug() << udp.writeDatagram(QByteArray("hello world"), QHostAddress("FF02::1"), 4321);
		qDebug() << udp.writeDatagram(QByteArray("hello world"), QHostAddress::Broadcast, 4321);
		QThread::sleep(5);
	}

	return 0;
}