#include <sys/types.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <stdio.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <netdb.h>
#include <memory.h>

// #define BUF_SIZE 64
// int main()
// {
//     int sock;
//     struct sockaddr_in addr;
//     char buf;
//     int bytes_read;

//     sock = socket(AF_INET, SOCK_DGRAM, 0);

//     addr.sin_family = AF_INET;
//     addr.sin_port = htons(3495);
//     addr.sin_addr.s_addr = htonl(INADDR_ANY);
//     bind(sock, (struct sockaddr *)&addr, sizeof(addr)) < 0;
//     printf("%s\n", "la");
//     while(1)
//     {
//     	printf("%s\n", "la");
//         bytes_read = recv(sock, &buf, 1, 0);
//         printf("%s\n", "la");
//         printf("%c", buf);
//         printf("%s\n", "la");
//         if (bytes_read<=0) break;
//     }
//     close(sock);
//     return 0;
// }



main()
{
   int s, namelen, client_address_size;
   struct sockaddr_in client, server;
   char buf[32];

   if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
   {
       exit(1);
   }


   server.sin_family      = AF_INET;  /* Server is in Internet Domain */
   server.sin_port        = 0;         /* Use any available port      */
   server.sin_addr.s_addr = INADDR_ANY;/* Server's Internet Address   */

   if (bind(s, (struct sockaddr *)&server, sizeof(server)) < 0)
   {
       exit(2);
   }
   /* Find out what port was really assigned and print it */
   namelen = sizeof(server);
   if (getsockname(s, (struct sockaddr *) &server, &namelen) < 0)
   {
       exit(3);
   }

   printf("Port assigned is %d\n", ntohs(server.sin_port));

   client_address_size = sizeof(client);

   if(recvfrom(s, buf, sizeof(buf), 0, (struct sockaddr *) &client,
            &client_address_size) <0)
   {
       exit(4);
   }

   printf("Received message %s from domain %s port %d internet\
 address %s\n",
       buf,
       (client.sin_family == AF_INET?"AF_INET":"UNKNOWN"),
       ntohs(client.sin_port),
       inet_ntoa(client.sin_addr));

   close(s);
}