Re: Simple multicast question

[Frank Kardel <kardel%netbsd.org@localhost>]

Ivo Vachkov wrote:
> I use something like this usually ...
>
>   
Thanks, close to what I use (except for REUSEADDR). But adding REUSEADDR 
and thus disabling the delivery optimization didn't help either. That 
needs more investigation
on my part.

My fragment now is (setting the bind address to INADDR_ANY on multicast 
addresses).

    fd = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
    
     if (fd == -1)
       {
         errx(EXIT_FAILURE, "socket(2) failed");
       }
    
     printf("Binding to %s\n", argv[1]);
     if (IN_CLASSD(ntohl(((struct sockaddr_in 
*)ai->ai_addr)->sin_addr.s_addr)))
       {
         printf("MCAST ADD MEMBERSHIP: ");
        
         memset(&mreq, 0, sizeof(mreq));
         mreq.imr_multiaddr = ((struct sockaddr_in 
*)ai->ai_addr)->sin_addr;
         mreq.imr_interface.s_addr = htonl(INADDR_ANY);
         ((struct sockaddr_in *)ai->ai_addr)->sin_addr.s_addr = 
htonl(INADDR_ANY);
         if (setsockopt(fd,
                        IPPROTO_IP,
                        IP_ADD_MEMBERSHIP,
                        (char *)&mreq,
                        sizeof(mreq)))
           {
             printf("FAIL %s (%d)\n", strerror(errno), errno);
           }
         else
           {
             printf("SUCCESS\n");
           }
       }

     if (bind(fd, ai->ai_addr, ai->ai_addrlen) == -1) ....


With that I see broadcast packets that are also flying around, but not 
multicast packets yet.

Thanks,
 Frank