code: func (out *DataOutputImpl) WriteLong(i int64) error {
  	err := out.WriteInt(int32(i >> 32))
  	if err == nil {
  		err = out.WriteInt(int32(i))
  	}
  	return err
  }
docs: /*
  Writes a long as eight bytes.
  
  64-bit unsigned integer written as eight bytes, high-order bytes first.
  */