ULtox
extern void ULtox ANSI((UShort*, ULong*, Long, int));
ULtox(L, B[0]->x, exp[0], rv[0]);
ULtox(M, B[1]->x, exp[1], rv[1]);
ULtox((UShort*)L, bits, expt, k);
ULtox(UShort *L, ULong *bits, Long expt, int k)