UNM_PROP_GET_INT
pval = UNM_PROP_GET_INT(dip, nm);
speed = UNM_PROP_GET_INT(dip, transfer_speed_propname);
speed = UNM_PROP_GET_INT(dip, speed_propname);
duplex = UNM_PROP_GET_INT(dip, duplex_propname);