Example program on how to use Boost ASIO to subscribe to a multicast server.

multicast_boost.cpp

#include <boost/asio.hpp>
#include <boost/exception/diagnostic_information.hpp> 

#define BUFFERSIZE 2048
using boost::asio::ip::udp;

int main(){
  boost::asio::io_service* io_service = nullptr;
  boost::asio::ip::udp::socket* socket = nullptr;
  
  int32_t port = 12911;
  std::string ip = "237.0.0.11";
  socket->open(boost::asio::ip::udp::v4());
  socket->set_option(udp::socket::reuse_address(true));
  socket->bind(udp::endpoint(boost::asio::ip::address_v4::any(), port));
  boost::asio::ip::address address =  boost::asio::ip::address::from_string(ip);
  socket->set_option(boost::asio::ip::multicast::join_group(address));
  
  char buffer[BUFFERSIZE];
  udp::endpoint senderEndpoint;
  
  while (true){
    try{
      bytesRead = socket->receive_from(boost::asio::buffer(buffer, BUFFERSIZE), senderEndpoint);
    }
    catch(const boost::exception &e)
    {
      std::cerr << "Error. Reason: " << boost::diagnostic_information(e) << '\n';
    }
  }
}