.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later .. _dmx_fwrite: ======================== Digital TV demux write() ======================== Name ---- Digital TV demux write() Synopsis -------- .. c:function:: ssize_t write(int fd, const void *buf, size_t count) :name: dvb-dmx-write Arguments --------- ``fd`` File descriptor returned by a previous call to :c:func:`open() `. ``buf`` Buffer with data to be written ``count`` Number of bytes at the buffer Description ----------- This system call is only provided by the logical device ``/dev/dvb/adapter?/dvr?``, associated with the physical demux device that provides the actual DVR functionality. It is used for replay of a digitally recorded Transport Stream. Matching filters have to be defined in the corresponding physical demux device, ``/dev/dvb/adapter?/demux?``. The amount of data to be transferred is implied by count. Return Value ------------ On success 0 is returned. On error -1 is returned, and the ``errno`` variable is set appropriately. .. tabularcolumns:: |p{2.5cm}|p{15.0cm}| .. flat-table:: :header-rows: 0 :stub-columns: 0 :widths: 1 16 - - ``EWOULDBLOCK`` - No data was written. This might happen if ``O_NONBLOCK`` was specified and there is no more buffer space available (if ``O_NONBLOCK`` is not specified the function will block until buffer space is available). - - ``EBUSY`` - This error code indicates that there are conflicting requests. The corresponding demux device is setup to receive data from the front- end. Make sure that these filters are stopped and that the filters with input set to ``DMX_IN_DVR`` are started. The generic error codes are described at the :ref:`Generic Error Codes ` chapter.