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linux-next/Documentation/media/uapi/dvb/fe-read-signal-strength.rst
Mauro Carvalho Chehab 9a721b9b4b media: dvb uAPI docs: adjust return value ioctl descriptions
There are several issues on the return value for ioctls:

- Text is confusing;
- Some error codes don't exist;
- The non-generic error codes should come before the text
  that points to the generic error codes;
- Tables don't contain column size hints;
- Some references are not marked as such.

Correct them.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-09-05 06:16:37 -04:00

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ReStructuredText

.. -*- coding: utf-8; mode: rst -*-
.. _FE_READ_SIGNAL_STRENGTH:
***********************
FE_READ_SIGNAL_STRENGTH
***********************
Name
====
FE_READ_SIGNAL_STRENGTH
.. attention:: This ioctl is deprecated.
Synopsis
========
.. c:function:: int ioctl( int fd, FE_READ_SIGNAL_STRENGTH, uint16_t *strength)
:name: FE_READ_SIGNAL_STRENGTH
Arguments
=========
``fd``
File descriptor returned by :c:func:`open() <dvb-fe-open>`.
``strength``
The signal strength value is stored into \*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.
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.