Question

I am starting Boost.Asio and trying to make examples given on official website work.
here`s client code:

 using boost::asio::ip::tcp;  int _tmain(int argc, _TCHAR* argv[]) {     try {         boost::asio::io_service io_service;          tcp::resolver resolver(io_service);         tcp::resolver::query query(argv[1], 'daytime');         tcp::resolver::iterator endpoint_iterator = resolver.resolve(query);         tcp::resolver::iterator end;          tcp::socket socket(io_service);         boost::system::error_code error = boost::asio::error::host_not_found;         while(error && endpoint_iterator != end) {             socket.close();             socket.connect(*endpoint_iterator++, error);         }         if (error)             throw boost::system::system_error(error);          for(;;) {             boost::array buf;             boost::system::error_code error;              std::size_t len = socket.read_some(boost::asio::buffer(buf), error);              if (error == boost::asio::error::eof)                 break; //connection closed cleanly by peer             else if (error)                 throw boost::system::system_error(error);              std::cout.write(buf.data(), len);         }     }     catch(std::exception& e) {         //...     }     return 0; } 

The question is – I can not find out what the parameters would be to run program from command prompt?

Answer 1

You would run the program with the IP or Hostname of the server you want to connect to. tcp::resolver::query takes the host to resolve or the IP as the first parameter and the name of the service (as defined e.g. in /etc/services on Unix hosts) – you can also use a numeric service identifier (aka port number). It returns a list of possible endpoints, as there might be several entries for a single host.