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+.. 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}|
+
+.. 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.