if_getvlantrunk
for (i = 0; if_getvlantrunk(ifp) != NULL && i < VLAN_N_VID; ++i) {
for (i = 0; if_getvlantrunk(rf->iwdev->netdev) != NULL && i < VLAN_N_VID; ++i) {
#define mxge_vlans_active(sc) if_getvlantrunk((sc)->ifp)
struct ifvlantrunk *if_getvlantrunk(if_t ifp);
if (if_getvlantrunk(_ifp) != NULL) \
(if_getvlantrunk(_ifp) != NULL ? (*vlan_devat_p)((_ifp), (_vid)) : NULL)