Boost asio socket write?

[bluefrog]

I'm attempting to learn boost asio. Starting off with the simple tests first.
This is a snippet of code that writes to a socket, but I keep getting the following exception thrown:

End point declared 
Socket Declared 
Error: system:111 connect: Connection refused

The code is a simple write, I have tried over a dozen different port numbers, none of which are in use, but the same error persists.

#include <boost/asio.hpp>
#include <iostream>
#include <string>

using namespace boost;

void write_to_socket(asio::ip::tcp::socket& sk, const std::string & msg ) {
  std::size_t total_write {0};  // bytes successfully witten
  std::size_t sz {msg.size()};
  
  // write_some returns the number of bytes sucessfully written
  while (total_write != sz ) {
    total_write += sk.write_some(asio::buffer(msg.c_str() + total_write, sz - total_write));
  }
  
}

void read_from_socket(asio::ip::tcp::socket& sk ) {
    /* to be coded */
}

int main() {
  std::string ip_addr {"127.0.0.1"};
  unsigned short port {5555};

  try {
    // initialise end point
    asio::ip::tcp::endpoint ep {asio::ip::address::from_string(ip_addr), port};
    
    std::cout << "End point declared \n";

    asio::io_service ios;

    // Configure socket with ios object and associated end point
    asio::ip::tcp::socket sk{ios, ep.protocol()};

    std::cout << "Socket Declared \n";
    sk.connect(ep); // connect socket to end point
    std::cout << "Socket Connected \n";

    write_to_socket(sk, "Hello World\n");
  }
  catch (system::system_error &e) {
    std::cout << "Error: " << e.code() << " " << e.what();
    return e.code().value();
  }
 
  return 0;
}

I can't see where the code is incorrect. Any suggestions anyone?

[nchambers]

Connection refused means there is nothing listening on that port to accept connections. whatever server you're running on that port isn't actually running on that port.

[bluefrog]

thanks, so unless I code a server part, the client would always come back with such an exception for the given End point.