Method HasReadBuffer

python/pyarrow/src/arrow/python/io.cc:168–174

  std::mutex& lock() { return lock_; }

  bool HasReadBuffer() {
    if (!checked_read_buffer_) {  // we don't want to check this each time
      has_read_buffer_ = PyObject_HasAttrString(file_.obj(), "read_buffer") == 1;
      checked_read_buffer_ = true;
    }
    return has_read_buffer_;
  }

 private:
  std::mutex lock_;