IEEE80211_F_USEBARKER
(((_ic)->ic_flags & (IEEE80211_F_SHPREAMBLE | IEEE80211_F_USEBARKER))\
ic->ic_flags &= ~IEEE80211_F_USEBARKER;
ic->ic_flags |= IEEE80211_F_USEBARKER;
if (ic->ic_flags & IEEE80211_F_USEBARKER)
ic->ic_flags &= ~IEEE80211_F_USEBARKER;
ic->ic_flags |= IEEE80211_F_USEBARKER;