#include <stdio.h>
#include <string.h>
#include <netinet/in.h>


int main(int argc, char **argv)
{
	struct sockaddr_in addr;
	int addr_len;
	struct ip_mreq req;
	int sock;
	char msg[256];

	memset(&addr, 0, sizeof(addr));

	if (argc < 3) {
		printf("Usage: <interface ip> <mcast group>\n");
		return 1;
	}

	sock = socket(AF_INET, SOCK_DGRAM, 0);
	addr.sin_family = AF_INET;
	addr.sin_port = htons(2000);
	if (bind(sock, (struct sockaddr *)&addr, sizeof(addr))) {
		perror("bind");
		return 1;
	}

	inet_aton(argv[1], &req.imr_interface);
	inet_aton(argv[2], &req.imr_multiaddr);

	if (setsockopt(sock, IPPROTO_IP, IP_ADD_MEMBERSHIP, &req,
							    sizeof(req))) {
		perror("setsockopt");
		return 1;
	}

	recvfrom(sock, msg, sizeof(msg), 0, (struct sockaddr *)&addr, &addr_len);

	printf("Message recieved: %s", msg);

	close (socket);
	return 0;
}