trwalk_state_t
trwalk_nextrec(trwalk_state_t *t)
trwalk_state_t *t, *oldest_t;
trwalk_state_t *t, *u;
mdb_free(t, sizeof (trwalk_state_t));
trwalk_state_t *t;
t = mdb_zalloc(sizeof (trwalk_state_t), UM_SLEEP);