Documentation/linux_tv/media/dvb/dmx-get-stc.rst

   1 .. -*- coding: utf-8; mode: rst -*-
   2
   3 .. _DMX_GET_STC:
   4
   5 DMX_GET_STC
   6 ===========
   7
   8 Description
   9 -----------
  10
  11 This ioctl call returns the current value of the system time counter
  12 (which is driven by a PES filter of type DMX_PES_PCR). Some hardware
  13 supports more than one STC, so you must specify which one by setting the
  14 num field of stc before the ioctl (range 0...n). The result is returned
  15 in form of a ratio with a 64 bit numerator and a 32 bit denominator, so
  16 the real 90kHz STC value is stc->stc / stc->base .
  17
  18 Synopsis
  19 --------
  20
  21 .. c:function:: int ioctl( int fd, int request = DMX_GET_STC, struct dmx_stc *stc)
  22
  23 Arguments
  24 ----------
  25
  26
  27
  28 .. flat-table::
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  31
  32
  33     -  .. row 1
  34
  35        -  int fd
  36
  37        -  File descriptor returned by a previous call to open().
  38
  39     -  .. row 2
  40
  41        -  int request
  42
  43        -  Equals DMX_GET_STC for this command.
  44
  45     -  .. row 3
  46
  47        -  struct dmx_stc \*stc
  48
  49        -  Pointer to the location where the stc is to be stored.
  50
  51
  52 Return Value
  53 ------------
  54
  55 On success 0 is returned, on error -1 and the ``errno`` variable is set
  56 appropriately. The generic error codes are described at the
  57 :ref:`Generic Error Codes <gen-errors>` chapter.
  58
  59
  60
  61 .. flat-table::
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  64
  65
  66     -  .. row 1
  67
  68        -  ``EINVAL``
  69
  70        -  Invalid stc number.
  71
  72
  73