#include <stdio.h>

#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <string.h>

int main()
{
  struct in6_addr sin6_addr;
  inet_pton(AF_INET6, "ff15::1234", &sin6_addr);

  struct sockaddr_in6 my_addr, from_addr;
  my_addr.sin6_family = AF_INET6;
  my_addr.sin6_port = htons(16789);
  my_addr.sin6_addr = sin6_addr;
  my_addr.sin6_flowinfo = 0;
  my_addr.sin6_scope_id = 0;

  int sock = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
  int yes = 1;
  setsockopt (sock, SOL_SOCKET, SO_BROADCAST, &yes, sizeof yes);
  setsockopt(sock, SOL_IPV6, IPV6_MULTICAST_HOPS, &yes, sizeof yes);
  setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof yes);
  bind (sock, (struct sockaddr *)&my_addr, sizeof my_addr);

  char buf[1024];
#if 0
  struct ipv6_mreq maddr;
  maddr.ipv6mr_multiaddr = sin6_addr;
  maddr.ipv6mr_interface = 0;

  setsockopt (sock, SOL_IPV6, IPV6_ADD_MEMBERSHIP, &maddr, sizeof maddr);
#else
  struct group_req gr;
  gr.gr_interface = 0;
  memcpy(&gr.gr_group, &my_addr, sizeof my_addr);
  setsockopt(sock, SOL_IPV6, MCAST_JOIN_GROUP, &gr, sizeof gr);
#endif

  sendto (sock, "Hello", strlen ("Hello"), 0, (struct sockaddr *)&my_addr,
	  sizeof my_addr);

  unsigned int sizeof_from_addr = sizeof from_addr;
  int len = recvfrom(sock, buf, sizeof buf, 0, (struct sockaddr *)&from_addr, 
		     &sizeof_from_addr);

  printf ("%d bytes received\n", len);

  return 0;
}