Method read_from_fd

python/python3/tornado/iostream.py:1658–1670

(self, buf: Union[bytearray, memoryview])

            del data

    def read_from_fd(self, buf: Union[bytearray, memoryview]) -> Optional[int]:
        try:
            return self._fio.readinto(buf)  # type: ignore
        except (IOError, OSError) as e:
            if errno_from_exception(e) == errno.EBADF:
                # If the writing half of a pipe is closed, select will
                # report it as readable but reads will fail with EBADF.
                self.close(exc_info=e)
                return None
            else:
                raise
        finally:
            del buf


def doctests() -> Any: