Method read

tools/python-3.11.9-amd64/Lib/_pyio.py:1654–1668

Read at most size bytes, returned as bytes. Only makes one system call, so less data may be returned than requested In non-blocking mode, returns None if no data is available. Return an empty bytes object at EOF.

(self, size=None)

            raise UnsupportedOperation('File not open for writing')

    def read(self, size=None):
        """Read at most size bytes, returned as bytes.

        Only makes one system call, so less data may be returned than requested
        In non-blocking mode, returns None if no data is available.
        Return an empty bytes object at EOF.
        """
        self._checkClosed()
        self._checkReadable()
        if size is None or size < 0:
            return self.readall()
        try:
            return os.read(self._fd, size)
        except BlockingIOError:
            return None

    def readall(self):
        """Read all data from the file, returned as bytes.