dt_xlator_member
mnp = dt_xlator_member(dxp, name);
mnp = dt_xlator_member(dxp, dnp->dn_right->dn_string);
if (dt_xlator_member(dxp, rp->dn_string) == NULL) {
extern struct dt_node *dt_xlator_member(dt_xlator_t *, const char *);