/*  Author:
    CS4153/CS6153 - Fall 2000
    Purpose:
*/

#include <iostream>
#include <stdlib.h>


#ifdef WIN32
/* for Windows */
#include <winsock2.h>
#else
/* for UNIX */
#include <sys/socket.h>
#include <netdb.h>
#define IPPROTO_IP           0
#define SOCKET_ERROR         -1
#define INADDR_NONE          0xffffffff
#endif

#define DAYTIME_PORT          13  /* port number for daytime server */

int main(int argc, char *argv[])
{
  unsigned long       ulAddrIP;
  struct              hostent *pHostEnt;
  struct sockaddr_in  SockAddrSend;
  struct sockaddr_in  SockAddrRecv;
  int                 iSock;
  char                szBuffer[1024];
  int                 iRecvSockAddrSize;

#ifdef WIN32
  /* for Windows */
  WORD                wVersionRequested;
  WSADATA             wsaData;

  /* setup windows sockets */
  wVersionRequested = MAKEWORD( 1, 1 ); 
  if(WSAStartup(wVersionRequested, &wsaData ) != 0)
  {
    std::cout << "Error initlializing Windows sockets\n";
    return -1;
  }
#else
/* for UNIX */
/* UNIX sockets do not need to be setup like WinSock */
#endif

  /* check for host address */

  /* initialize host socket address */

  /* figure out remote host's IP address */

  /* create an unbound datagram (UDP) socket */
  iSock = socket(???, ???, ???);

  /* No need to establish a connection with the host */

  /* clear receive buffer */

  /* send dummy data to UDP DayTime server to inform it that we
     are waiting to receive data. */
  if (sendto(???, ???, ???, ???, ???, ???) == SOCKET_ERROR)
  {
    std::cout << "Send error.\n";
    return -1;
  }
  
  /* receive data over socket */
  if (recvfrom(???, ???, ???, ???, ???, ???) == SOCKET_ERROR)
  {
    std::cout << "Receive error.\n";
    return -1;
  }

  printf("UDP DayTime server on %s returns %s\n", argv[1], szBuffer);

#ifdef WIN32
  /* for Windows only */
  closesocket(iSock); /* close the socket */
  WSACleanup();       /* cleanup WInSock */
#else
  /* for UNIX */
  close(iSock);       /* close the socket */
  /* UNIX sockets do not need to be cleanedup like WinSock */
#endif

  return 0;
}