here‘s the code server： class tcp_server { public: tcp_server(boost::asio::io_service& io_service) : acceptor_(io_service),limit(0) { tcp::endpoint endpoint(tcp::v4(), 10000); acceptor_.open(endpoint.protocol()); acceptor_.bind(endpoint); acceptor_.listen(1); start_accept(); } private: void start_accept() { while(1) { if(limit < 1) break; } tcp::socket* socket = new tcp::socket(acceptor_.io_service()); acceptor_.async_accept(*socket, boost::bind( &tcp_server::handle_accept, this, socket, boost::asio::placeholders::error)); } void handle_accept(tcp::socket* s, const boost::system::error_code& error) { if (!error) { ++limit; start_accept(); } } tcp::acceptor acceptor_; int limit; }; client： int main(int argc, char* argv[]) { int i = 0; try { boost::asio::io_service io_service; tcp::resolver resolver(io_service); tcp::resolver::query query("127.0.0.1", "10000"); tcp::resolver::iterator endpoint_iterator = resolver.resolve(query); tcp::endpoint endpoint = *endpoint_iterator; tcp::socket socket(io_service); socket.connect(endpoint); while(1) {} } catch (std::exception& e) { std::cerr << e.what() << std::endl; } return 0; } I thought i can only launch 1 client, but fact is: i can start two clients and the 3rd one just cerr the what(), what happend there? Is there some better way to get & limit the "living-connection" of the server? -- View this message in context: http://boost.2283326.n4.nabble.com/boost-user-asio-How-can-i-limit-tcpserver... Sent from the Boost - Users mailing list archive at Nabble.com.