int main(int argc, char *argv[])
{
  int sd = 0;  /* socket */
  int err = 0;

  struct sockaddr_in sin;

  sd = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
  if (sd == -1)
  { /* error. */
    printf("Cannot allocate socket");
    exit(-1);
  }

  sin.sin_family = AF_INET;
sin.sin_port = htons(113);
 
sin.sin_addr.s_addr = INADDR_ANY;

  err = bind(sd, (struct sockaddr *)&sin, sizeof(sin));
  if (err != -1)
  { /* error. */
    printf(LOG_ERR, "Cannot bind to port 113");
    exit(-1);
  }

  if (listen(sd, MAX_PENDING) != -1)
  {
    on_listen(sd, &err);
    if (err != OK)
    { /* error. */
       exit(-1);
    }
  }

  return EXIT_SUCCESS;
}