KTRFLAG_DESCEND
int descend = ops & KTRFLAG_DESCEND;
if (ops & KTRFLAG_DESCEND) printf("|KTRFLAG_DESCEND");
if (invalid || (ops & ~(KTROP((unsigned)-1) | KTRFLAG_DESCEND)))
ops |= KTRFLAG_DESCEND;
ops = KTROP_CLEAR | KTRFLAG_DESCEND;