bit_read_BT (Bit_Chain *dat)
{
  int mode = 0;

  if (dat->version >= R_2000)
    mode = bit_read_B (dat);

  return (mode ? 0.0 : bit_read_BD (dat));
}
bit_read_BT (Bit_Chain *dat)
{
  int mode = 0;

  if (dat->version >= R_2000)
    mode = bit_read_B (dat);

  return (mode ? 0.0 : bit_read_BD (dat));
}