1*4882a593Smuzhiyun.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later 2*4882a593Smuzhiyun.. c:namespace:: DTV.dmx 3*4882a593Smuzhiyun 4*4882a593Smuzhiyun.. _DMX_GET_STC: 5*4882a593Smuzhiyun 6*4882a593Smuzhiyun=========== 7*4882a593SmuzhiyunDMX_GET_STC 8*4882a593Smuzhiyun=========== 9*4882a593Smuzhiyun 10*4882a593SmuzhiyunName 11*4882a593Smuzhiyun---- 12*4882a593Smuzhiyun 13*4882a593SmuzhiyunDMX_GET_STC 14*4882a593Smuzhiyun 15*4882a593SmuzhiyunSynopsis 16*4882a593Smuzhiyun-------- 17*4882a593Smuzhiyun 18*4882a593Smuzhiyun.. c:macro:: DMX_GET_STC 19*4882a593Smuzhiyun 20*4882a593Smuzhiyun``int ioctl(int fd, DMX_GET_STC, struct dmx_stc *stc)`` 21*4882a593Smuzhiyun 22*4882a593SmuzhiyunArguments 23*4882a593Smuzhiyun--------- 24*4882a593Smuzhiyun 25*4882a593Smuzhiyun``fd`` 26*4882a593Smuzhiyun File descriptor returned by :c:func:`open()`. 27*4882a593Smuzhiyun 28*4882a593Smuzhiyun``stc`` 29*4882a593Smuzhiyun Pointer to :c:type:`dmx_stc` where the stc data is to be stored. 30*4882a593Smuzhiyun 31*4882a593SmuzhiyunDescription 32*4882a593Smuzhiyun----------- 33*4882a593Smuzhiyun 34*4882a593SmuzhiyunThis ioctl call returns the current value of the system time counter 35*4882a593Smuzhiyun(which is driven by a PES filter of type :c:type:`DMX_PES_PCR <dmx_ts_pes>`). 36*4882a593SmuzhiyunSome hardware supports more than one STC, so you must specify which one by 37*4882a593Smuzhiyunsetting the :c:type:`num <dmx_stc>` field of stc before the ioctl (range 0...n). 38*4882a593SmuzhiyunThe result is returned in form of a ratio with a 64 bit numerator 39*4882a593Smuzhiyunand a 32 bit denominator, so the real 90kHz STC value is 40*4882a593Smuzhiyun``stc->stc / stc->base``. 41*4882a593Smuzhiyun 42*4882a593SmuzhiyunReturn Value 43*4882a593Smuzhiyun------------ 44*4882a593Smuzhiyun 45*4882a593SmuzhiyunOn success 0 is returned. 46*4882a593Smuzhiyun 47*4882a593SmuzhiyunOn error -1 is returned, and the ``errno`` variable is set 48*4882a593Smuzhiyunappropriately. 49*4882a593Smuzhiyun 50*4882a593Smuzhiyun.. tabularcolumns:: |p{2.5cm}|p{15.0cm}| 51*4882a593Smuzhiyun 52*4882a593Smuzhiyun.. flat-table:: 53*4882a593Smuzhiyun :header-rows: 0 54*4882a593Smuzhiyun :stub-columns: 0 55*4882a593Smuzhiyun :widths: 1 16 56*4882a593Smuzhiyun 57*4882a593Smuzhiyun - .. row 1 58*4882a593Smuzhiyun 59*4882a593Smuzhiyun - ``EINVAL`` 60*4882a593Smuzhiyun 61*4882a593Smuzhiyun - Invalid stc number. 62*4882a593Smuzhiyun 63*4882a593SmuzhiyunThe generic error codes are described at the 64*4882a593Smuzhiyun:ref:`Generic Error Codes <gen-errors>` chapter. 65