NM_FT_NULL
if (next == NM_FT_NULL && brd_next == NM_FT_NULL)
d->bq_head = d->bq_tail = NM_FT_NULL; /* cleanup */
brddst->bq_head = brddst->bq_tail = NM_FT_NULL; /* cleanup */
dstq[j].bq_head = dstq[j].bq_tail = NM_FT_NULL;
ft[ft_i].ft_next = NM_FT_NULL;
if (d->bq_head == NM_FT_NULL) { /* new destination */
if (brddst->bq_head != NM_FT_NULL) {
if (dst_ents[d_i].bq_head == NM_FT_NULL)