| .. 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() <dvb-ca-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 <gen-errors>` chapter. |
