IFM_NMASK
ifmr->ifm_current = (ifmr->ifm_current & ~(IFM_NMASK|IFM_TMASK)) |
#define IFM_NMAX IFM_NMASK /* highest Network type */
#define IFM_TYPE(x) ((x) & IFM_NMASK)
switch(ifmr.ifm_active & IFM_NMASK) {