ubuntu-linux-kernel/Documentation/media/uapi/dvb/fe-read-snr.rst

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.. -*- coding: utf-8; mode: rst -*-
.. _FE_READ_SNR:
***********
FE_READ_SNR
***********
Name
====
FE_READ_SNR
.. attention:: This ioctl is deprecated.
Synopsis
========
.. c:function:: int ioctl(int fd, FE_READ_SNR, int16_t *snr)
:name: FE_READ_SNR
Arguments
=========
``fd``
File descriptor returned by :c:func:`open() <dvb-fe-open>`.
``snr``
The signal-to-noise ratio is stored into \*snr.
Description
===========
This ioctl call returns the signal-to-noise ratio for the signal
currently received by the front-end. For this command, read-only access
to the device is sufficient.
Return Value
============
On success 0 is returned.
On error -1 is returned, and the ``errno`` variable is set
appropriately.
Generic error codes are described at the
:ref:`Generic Error Codes <gen-errors>` chapter.