#include <boost/asio.hpp>
#include <iostream>
#include <ctime>
#include <exception>

using boost::asio::ip::tcp;
using namespace std;

char* cmdname;

void usage() {
   cerr << "Usage: " << cmdname << " port" << endl;
   exit(1);
}

int main(int argc, char* argv[]) {
   // process command line arguments
   cmdname = *argv++; --argc;
   if (argc != 1) usage();
   unsigned int port(atoi(argv[0]));

   boost::asio::io_service io_service;
   tcp::acceptor acceptor(io_service, tcp::endpoint(tcp::v4(), port));
   acceptor.set_option(boost::asio::ip::tcp::acceptor::reuse_address(true));
   try {
      for(;;) {
	 tcp::socket socket(io_service);
	 acceptor.accept(socket);
	 try {
	    char timebuf[32]; time_t clock; time(&clock);
	    ctime_r(&clock, timebuf, sizeof timebuf);
	    std::string msg(timebuf);
	    boost::asio::write(socket, boost::asio::buffer(msg),
	       boost::asio::transfer_all());
	 } catch (exception& e) {
	    cerr << cmdname << ": " << e.what() << endl;
	 }
      }
   } catch (exception& e) {
      cerr << cmdname << ": " << e.what() << endl;
   }
}