MAC_PLUGIN_IDENT_IPV6
{ IPTUN_TYPE_IPV6, MAC_PLUGIN_IDENT_IPV6, IPV6_VERSION,
mtrp->mtr_ident = MAC_PLUGIN_IDENT_IPV6;
(void) mactype_unregister(MAC_PLUGIN_IDENT_IPV6);
if ((err = mactype_unregister(MAC_PLUGIN_IDENT_IPV6)) != 0)