| .. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later |
| .. c:namespace:: DTV.dmx |
| |
| .. _DMX_GET_STC: |
| |
| =========== |
| DMX_GET_STC |
| =========== |
| |
| Name |
| ---- |
| |
| DMX_GET_STC |
| |
| Synopsis |
| -------- |
| |
| .. c:macro:: DMX_GET_STC |
| |
| ``int ioctl(int fd, DMX_GET_STC, struct dmx_stc *stc)`` |
| |
| Arguments |
| --------- |
| |
| ``fd`` |
| File descriptor returned by :c:func:`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}| |
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| .. flat-table:: |
| :header-rows: 0 |
| :stub-columns: 0 |
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| - .. row 1 |
| |
| - ``EINVAL`` |
| |
| - Invalid stc number. |
| |
| The generic error codes are described at the |
| :ref:`Generic Error Codes <gen-errors>` chapter. |