several questions...

Tiago Jorge tjpj at
Fri Mar 18 15:50:37 CET 2005

hello again...
i've been trying to broadcast a message through UDP and configure the 
ethernet card bue i've not sucedded yet...

1st question - have you ever tried to do that?

2nd question - i'm trying to set the broadcast adress directly in the 
NIC. i've tried to ioctl using the change parameter but haven't 
sucedded. this code works on linux but not with l4:

int if_set_broadaddr(const char *ifn)
  int return_val, fd = -1;
  struct ifreq ifr; /* points to one interface returned from ioctl */
  struct in_addr *broadaddr;
  struct sockaddr_in sa;

  fd = socket (PF_INET, SOCK_DGRAM, 0);

  if (fd < 0) {
    LOG("Error opening socket for interface");
    return -1;

  strncpy (ifr.ifr_name, ifn, sizeof(ifr.ifr_name));
  if (!inet_aton("", &sa.sin_addr))
    LOG("no valid IP address");

  sa.sin_family = AF_INET;
  memcpy(&ifr.ifr_broadaddr, &sa, sizeof(struct sockaddr));

  if (ioctl(fd, SIOCSIFBRDADDR, &ifr) < 0)
    LOG("ioctl(SIOCSIFBRDADDR) returns");

  close (fd);
  return return_val;

is there any problem with the SIOCSIFBRDADDR flag?

thanks in advance

Tiago Jorge

More information about the l4-hackers mailing list