//compile with g++ main.cpp -lboost_system -pthread #include int main() { boost::asio::io_context io_context; boost::asio::ip::tcp::socket sock(io_context); boost::asio::ip::tcp::resolver resolver(io_context); boost::asio::ip::tcp::resolver::query query("localhost", "4321"); boost::asio::connect(sock, resolver.resolve(query)); boost::asio::write(sock, boost::asio::buffer("Hello world socket\r\n")); return 0; }