linux/Documentation/media/uapi/dvb/dmx-get-stc.rst
Mauro Carvalho Chehab cf8076c314 [media] docs-rst: Convert DVB uAPI to use C function references
Name all ioctl references and make them match the ioctls that
are documented. That will improve the cross-reference index,
as it will have all ioctls and syscalls there.

While here, improve the documentation, marking the deprecated
ioctls, and making the non-deprecated ones more like the rest
of the media book.

Also, add a notice for ioctls that still require documentation.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-08-22 21:23:34 -03:00

59 lines
1.1 KiB
ReStructuredText

.. -*- coding: utf-8; mode: rst -*-
.. _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 the location where the stc 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 DMX_PES_PCR). Some hardware
supports more than one STC, so you must specify which one by setting the
num 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 and the ``errno`` variable is set
appropriately. The generic error codes are described at the
:ref:`Generic Error Codes <gen-errors>` chapter.
.. flat-table::
:header-rows: 0
:stub-columns: 0
- .. row 1
- ``EINVAL``
- Invalid stc number.