Entry *nil = (Entry *) 0;

void
rtl_init(Entry *q)
{
	q->next = nil;
	q->tail = q;
}

int
cas(Entry **ptr, Entry *old, Entry *new)
{	/* Compare and swap: atomically */
	if (*ptr == old)
	{	*ptr = new;
		return 1;
	} /* else */
	return 0;
}
