I've made unit test for this problem. Server.h: #pragma once #include #include #include #include <iostream> class Server { public: AssistGui(boost::asio::io_service &); ~AssistGui(void); void accept(const boost::system::error_code& e); void sendMsg(const char *msg, unsigned int size); private: boost::asio::io_service &io; boost::asio::ip::tcp::socket _client; boost::asio::ip::tcp::acceptor _acceptor; }; Server.cpp: #include "Server.h" using boost::asio::ip::tcp; Server::Server(boost::asio::io_service &ios) : io(ios), _client(ios), _acceptor(ios, tcp::endpoint(tcp::v4(), 14242)) { _acceptor.async_accept(_client, boost::bind(&Server::accept, this, boost::asio::placeholders::error)); } void Server::sendMsg(const char *msg, unsigned int size) { } Server::~Server(void) { } void Server::accept(const boost::system::error_code& e) { // same error :-( : "Already open" } int main() { boost::asio::io_service ios; Server s(ios); ios.run(); } The error is still the same "Already open". _WIN32_WINNT=0x0501 is defined. I tried to change port. No warnings at program compilation. Can you help me? Thank you Cyprien DIOT ----- Mail original ----- De: "Igor R" À: boost-users@lists.boost.org Envoyé: Jeudi 10 Mars 2011 00:42:24 Objet: Re: [Boost-users] [ASIO] async_accept : Error m_val 1.

m_val = 1; m_cat = 0x00ab8d00 instance;  | [boost::asio::error::detail::misc_category] = {...}  | boost::noncopyable_::noncopyable = {...}  | __vfptr = 0x00a8bf18 const boost::asio::error::detail::misc_category::`vftable'

Use message() member function of error_code to see the error description. IIUC, in your case it should be "Already open", i.e. you're trying to accept new connection to a socket which was already open. _______________________________________________ Boost-users mailing list Boost-users@lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users