Documentation/linux_tv/media/dvb/FE_READ_SIGNAL_STRENGTH.rst

.. -*- coding: utf-8; mode: rst -*-

.. _FE_READ_SIGNAL_STRENGTH:

***********************
FE_READ_SIGNAL_STRENGTH
***********************

DESCRIPTION

This ioctl call returns the signal strength value for the signal
currently received by the front-end. For this command, read-only access
to the device is sufficient.

SYNOPSIS

int ioctl( int fd, int request =
:ref:`FE_READ_SIGNAL_STRENGTH <FE_READ_SIGNAL_STRENGTH>`,
uint16_t *strength);

PARAMETERS



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    -  .. row 1

       -  int fd

       -  File descriptor returned by a previous call to open().

    -  .. row 2

       -  int request

       -  Equals
          :ref:`FE_READ_SIGNAL_STRENGTH <FE_READ_SIGNAL_STRENGTH>`
          for this command.

    -  .. row 3

       -  uint16_t *strength

       -  The signal strength value is stored into *strength.


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.


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.. ------------------------------------------------------------------------------