#include <sys/stat.h>
#include <signal.h>
#include <fcntl.h>
#include <sys/types.h>
#include <errno.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <netinet/in.h>
#include <netinet/ip_var.h>
#include <netdb.h>
#include <sys/time.h>
#include <signal.h>
#include <string.h>
#ifndef NULL
#define NULL (void*)0
#endif
#ifndef INADDR_NONE
#define INADDR_NONE 0xffffffff
#endif


#define BUFSIZE 100

char buff[BUFSIZE];

#define SERV_UDP_PORT 2047

main(int argc, char *argv[])
{
  int sockfd,i,s,alen,hlen,mlen,count;
  struct sockaddr_in serv_addr;
  struct ip_mreq mreq;
  unsigned long inaddr;

  if (argc==1) {
          printf("USAGE: recv_udpm A.B.C.D\n");
          exit(0);
  }

  /* open UDP socket  */

  if ((sockfd = socket(AF_INET,SOCK_DGRAM,0)) < 0 ) {
      perror("error open socket");
       exit(-1);
    }
   alen = sizeof(serv_addr);
   memset(&serv_addr, NULL, alen);
   serv_addr.sin_family = AF_INET;
   serv_addr.sin_addr.s_addr = htonl(INADDR_ANY);
   /* Try to convert group address as a dotted-decimal number.  */
   if ( (inaddr = inet_addr(argv[1])) != INADDR_NONE) {
                                        /* it's dotted-decimal */
/*    memcpy(&serv_addr.sin_addr, &inaddr, sizeof(inaddr));*/
   } else {

      printf("Problems with this group address...\n");
      exit(0);
   }

   serv_addr.sin_port        = htons(SERV_UDP_PORT);
   if (bind(sockfd, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0) {
      perror("bind");
      exit(-1);
   }

   mlen = sizeof(mreq);
   memset(&mreq, NULL, mlen);
   mreq.imr_multiaddr.s_addr = inaddr;
   mreq.imr_interface.s_addr = INADDR_ANY;
   setsockopt(sockfd, IPPROTO_IP, IP_ADD_MEMBERSHIP, (char *) &mreq, mlen);


   count = 0;
    for (;;) {
           i = recvfrom(sockfd,buff,BUFSIZE,0,(struct sockaddr *)&serv_addr,&alen);
           if (i < 0) {
               printf("rec error");
               exit(1);
            }
           printf("rec-data %d   ",count++);
           for (s = 0; s < i; s++)     /* print data received*/
              printf("%c",buff[s]);
           printf("\n");
   }
}