static inline int cpy_str_at_offset(void *new, const void *old, size_t offset)
{
	char **o = (char **) ((char *) old + offset);
	char **n = (char **) ((char *) new + offset);

	if (*n)
		return 0;	/* already set, don't overwrite */

	return update_str(n, *o);
}
static inline int cpy_str_at_offset(void *new, const void *old, size_t offset)
{
	char **o = (char **) ((char *) old + offset);
	char **n = (char **) ((char *) new + offset);

	if (*n)
		return 0;	 

	return update_str(n, *o);
}