linux/Documentation/media/uapi/dvb/fe-get-property.rst
Mauro Carvalho Chehab 60c2820d0f doc_rst: rename the media Sphinx suff to Documentation/media
The name of the subsystem is "media", and not "linux_tv". Also,
as we plan to add other stuff there in the future, let's
rename also the media uAPI book to media_uapi, to make it
clearer.

No functional changes.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-07-08 11:59:40 -03:00

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1.6 KiB
ReStructuredText

.. -*- coding: utf-8; mode: rst -*-
.. _FE_GET_PROPERTY:
**************************************
ioctl FE_SET_PROPERTY, FE_GET_PROPERTY
**************************************
Name
====
FE_SET_PROPERTY - FE_GET_PROPERTY - FE_SET_PROPERTY sets one or more frontend properties. - FE_GET_PROPERTY returns one or more frontend properties.
Synopsis
========
.. cpp:function:: int ioctl( int fd, int request, struct dtv_properties *argp )
Arguments
=========
``fd``
File descriptor returned by :ref:`open() <frontend_f_open>`.
``request``
FE_SET_PROPERTY, FE_GET_PROPERTY
``argp``
pointer to struct :ref:`dtv_properties <dtv-properties>`
Description
===========
All DVB frontend devices support the ``FE_SET_PROPERTY`` and
``FE_GET_PROPERTY`` ioctls. The supported properties and statistics
depends on the delivery system and on the device:
- ``FE_SET_PROPERTY:``
- This ioctl is used to set one or more frontend properties.
- This is the basic command to request the frontend to tune into
some frequency and to start decoding the digital TV signal.
- This call requires read/write access to the device.
- At return, the values are updated to reflect the actual parameters
used.
- ``FE_GET_PROPERTY:``
- This ioctl is used to get properties and statistics from the
frontend.
- No properties are changed, and statistics aren't reset.
- This call only requires read-only access to the device.
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.