vlc.MediaReadCb
===============

.. py:class:: vlc.MediaReadCb

   Bases: :py:obj:`ctypes.c_void_p`


   Callback prototype to read data from a custom bitstream input media.

   .. note:: If no data is immediately available, then the callback should sleep.
   .. warning:: The application is responsible for avoiding deadlock situations.
       In particular, the callback should return an error if playback is stopped;
       if it does not return, then :func:`libvlc_media_player_stop` will never return.

   :param opaque: private pointer as set by the :class:`MediaOpenCb`.
       callback.
   :param buf: start address of the buffer to read data into.
   :param len: bytes length of the buffer.

   :return: strictly positive number of bytes read, 0 on end-of-stream,
       or -1 on non-recoverable error.

   Initialize self.  See help(type(self)) for accurate signature.