exit (failures ? 1 : 0);
return failures ? 1 : 0;
main (void){  int failures = 0;  struct if_nameindex *idx = if_nameindex (), *p;  if (idx == NULL)    {      if (errno != ENOSYS)	{	  printf ("Couldn't get any interfaces.\n");	  exit (1);	}      /* The function is simply not implemented.  */      exit (0);    }  printf ("Idx            Name | Idx           Name\n");  for (p = idx; p->if_index || p->if_name; ++p)    {      char buf[IFNAMSIZ];      unsigned int ni;      int result;      printf ("%3d %15s | ", p->if_index, p->if_name);      printf ("%3d", ni = if_nametoindex (p->if_name));      printf ("%15s", if_indextoname (p->if_index, buf));      result = (ni != p->if_index || (strcmp (buf, p->if_name)));      if (ni == p->if_index)	/* We have to make sure that this is not an alias with the	   same interface number.  */	if (p->if_index == if_nametoindex (buf))	  result = 0;      printf ("%10s", result ? "fail" : "okay");      printf ("\n");      failures += result;    }  if_freenameindex (idx);  exit (failures ? 1 : 0);}