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diff --git a/Documentation/media/uapi/dvb/dmx-fopen.rst b/Documentation/media/uapi/dvb/dmx-fopen.rst new file mode 100644 index 000000000..55628a18b --- /dev/null +++ b/Documentation/media/uapi/dvb/dmx-fopen.rst @@ -0,0 +1,91 @@ +.. -*- coding: utf-8; mode: rst -*- + +.. _dmx_fopen: + +======================= +Digital TV demux open() +======================= + +Name +---- + +Digital TV demux open() + + +Synopsis +-------- + +.. c:function:: int open(const char *deviceName, int flags) + :name: dvb-dmx-open + +Arguments +--------- + +``name`` + Name of specific Digital TV demux device. + +``flags`` + A bit-wise OR of the following flags: + +.. tabularcolumns:: |p{2.5cm}|p{15.0cm}| + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + :widths: 1 16 + + - + - ``O_RDONLY`` + - read-only access + + - + - ``O_RDWR`` + - read/write access + + - + - ``O_NONBLOCK`` + - open in non-blocking mode + (blocking mode is the default) + + +Description +----------- + +This system call, used with a device name of ``/dev/dvb/adapter?/demux?``, +allocates a new filter and returns a handle which can be used for +subsequent control of that filter. This call has to be made for each +filter to be used, i.e. every returned file descriptor is a reference to +a single filter. ``/dev/dvb/adapter?/dvr?`` is a logical device to be used +for retrieving Transport Streams for digital video recording. When +reading from this device a transport stream containing the packets from +all PES filters set in the corresponding demux device +(``/dev/dvb/adapter?/demux?``) having the output set to ``DMX_OUT_TS_TAP``. +A recorded Transport Stream is replayed by writing to this device. + +The significance of blocking or non-blocking mode is described in the +documentation for functions where there is a difference. It does not +affect the semantics of the ``open()`` call itself. A device opened +in blocking mode can later be put into non-blocking mode (and vice versa) +using the ``F_SETFL`` command of the fcntl system call. + + +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 + + - - ``EMFILE`` + - “Too many open files”, i.e. no more filters available. + +The generic error codes are described at the +:ref:`Generic Error Codes <gen-errors>` chapter. |