John Urberg writes:

I'm using boost asio to send out multicast hailing messages every 15 seconds from an ActiveX control using boost 1.35.0 and VC9. I had a proof of concept ActiveX working fine, but in my production ActiveX, I'm able to send the first message successfully, but every subsequent message returns a 10009 error.

Here is the code:

MulticastServer::MulticastServer( boost::asio::io_service& io_service, string addr, int port, int seconds) : endpoint(boost::asio::ip::address::from_string(addr), port) , socket(io_service, endpoint.protocol()) , timer(io_service) , server_port(server_port) , seconds(seconds) { socket.set_option(boost::asio::ip::multicast::hops(32)); } void MulticastServer::Start() { HandleTimeout(boost::system::error_code()); } void MulticastServer::HandleTimeout(const boost::system::error_code& error) { string message = BuildHailMessage(); std::strcpy(buffer, message.c_str()); socket.async_send_to( boost::asio::buffer(buffer, message.length()), endpoint, boost::bind( &MulticastServer::HandleSendTo, this, boost::asio::placeholders::error)); } void MulticastServer::HandleSendTo(const boost::system::error_code& error) { timer.expires_from_now(boost::posix_time::seconds(seconds)); timer.async_wait(boost::bind(&MulticastServer::HandleTimeout, this, boost::asio::placeholders::error)); }

Any ideas what would cause this error message?

Also, if I use a string instead of char[] for the buffer, I always receive a 'string iterator not dereferencable' assertion failure. How could I fix that so I can use std::string instead of a char[] buffer?

Some more information. I tried using sync io and I don't have issues sending multiple times: while (1) { size_t rc = socket.send_to(boost::asio::buffer(buffer, message.length()), endpoint); std::cout << "Send to returned " << rc << std::endl; boost::this_thread::sleep(boost::posix_time::seconds(15)); } Here is how I'm starting the MulticastServer: void SocketClientConnector::Start(const string& connectionName) throw(exception) { this->name = connectionName; service_thread = new boost::thread(boost::bind(&SocketClientConnector::RunServiceThread, this)); } void SocketClientConnector::RunServiceThread() { try { MulticastServer server(io_service, group_address, group_port, server_port, name, id, interval); server.Start(); } catch (exception& e) { std::cout << e.what() << std::endl; } io_service.run(); } This is quite confusing for me as I pulled this code from the multicast_sender example and also had it working in a separate example ActiveX. The only thing I'm doing different is this code is located in a separate MFC DLL that is called from the ActiveX. Any ideas would be appreciated. Thanks, John

error 10009 probably means that the handle of your socket is invalid. Maybe, the socket object is destroyed? Put a breakpoint at MulticastServer destructor and look when you come there and why... 2008/8/9, John Urberg :

I'm using boost asio to send out multicast hailing messages every 15 seconds from an ActiveX control using boost 1.35.0 and VC9. I had a proof of concept ActiveX working fine, but in my production ActiveX, I'm able to send the first message successfully, but every subsequent message returns a 10009 error.