#include <sys/socket.h>
#include <netinet/in.h>
#include <stdio.h>
#include <errno.h>

int main ()
{
  char buffer[64];  
  int fd = socket (PF_INET, SOCK_RAW, IPPROTO_RAW);
  if (fd < 0)
    {
      fprintf (stderr, "Can't create raw socket: %s\n", strerror (errno));
      return 1;
    }
    
  /* On a buggy kernel the next line generates an oops, 
     on a fixed kernel it returns -1 with errno == EINVAL. */
  sendto (fd, buffer, 64, 0, NULL, 16);  
  printf ("sendto() => %s\n", strerror (errno));
  
  close (fd);
}