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diff --git a/Documentation/userspace-api/media/dvb/dmx-get-stc.rst b/Documentation/userspace-api/media/dvb/dmx-get-stc.rst new file mode 100644 index 000000000000..026a884edb0a --- /dev/null +++ b/Documentation/userspace-api/media/dvb/dmx-get-stc.rst @@ -0,0 +1,73 @@ +.. Permission is granted to copy, distribute and/or modify this +.. document under the terms of the GNU Free Documentation License, +.. Version 1.1 or any later version published by the Free Software +.. Foundation, with no Invariant Sections, no Front-Cover Texts +.. and no Back-Cover Texts. A copy of the license is included at +.. Documentation/userspace-api/media/fdl-appendix.rst. +.. +.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections + +.. _DMX_GET_STC: + +=========== +DMX_GET_STC +=========== + +Name +---- + +DMX_GET_STC + + +Synopsis +-------- + +.. c:function:: int ioctl( int fd, DMX_GET_STC, struct dmx_stc *stc) + :name: DMX_GET_STC + +Arguments +--------- + +``fd`` + File descriptor returned by :c:func:`open() <dvb-dmx-open>`. + +``stc`` + Pointer to :c:type:`dmx_stc` where the stc data is to be stored. + + +Description +----------- + +This ioctl call returns the current value of the system time counter +(which is driven by a PES filter of type :c:type:`DMX_PES_PCR <dmx_ts_pes>`). +Some hardware supports more than one STC, so you must specify which one by +setting the :c:type:`num <dmx_stc>` field of stc before the ioctl (range 0...n). +The result is returned in form of a ratio with a 64 bit numerator +and a 32 bit denominator, so the real 90kHz STC value is +``stc->stc / stc->base``. + + +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 + + - .. row 1 + + - ``EINVAL`` + + - Invalid stc number. + + +The generic error codes are described at the +:ref:`Generic Error Codes <gen-errors>` chapter. |