units_size
size = units_size(units, disk.dk_size, &ut);
size = units_size(units, end - start + 1, &ut);
size = units_size(units, DL_GETDSIZE(&dl), &ut);
size = units_size(units, (start > end) ? 0 : end - start + 1, &ut);
double units_size(const char *, const uint64_t,
size = units_size(units, prt->prt_ns, &ut);