__big_float_times_power
extern void __big_float_times_power(_big_float *pbf, int mult, int n,
__big_float_times_power(pb, 10, pd->bexponent, nsig, ppb);
__big_float_times_power(&d, 2, powtwo, sigdigits, &pbd);
__big_float_times_power(pd, 2, pb->bexponent, nsig, ppd);
__big_float_times_power(bf, 10, powten, sigbits, &pbf);
__big_float_times_power(bf, 10, powten,