h the case of addresses that lack a zone. Some of them are best-effort for efficiency (e.g. the PCB bind and connect API calls' attempts to add missing zones); ultimately the IPv6 output handler (<a class="el" href="ip6_8h.html#a58bd3c9ce332731fac82b89c77be4f56">ip6_output_if_src</a>) will set a zone if necessary.</p>
<p>Aside from dealing with scoped addresses lacking a zone, a proper IPv6 implementation must also ensure that a packet with a scoped source and/or destination address does not leave its zone.