IPIF_CHANGING
{ "CH", IPIF_CHANGING, IPIF_CHANGING},
((ipif)->ipif_state_flags & IPIF_CHANGING)
ipif->ipif_state_flags |= IPIF_CHANGING;
ipif->ipif_state_flags |= IPIF_CHANGING;
ipif->ipif_state_flags &= ~IPIF_CHANGING;
ipif->ipif_state_flags &= ~IPIF_CHANGING;
ipif->ipif_state_flags &= ~IPIF_CHANGING;