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.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
.. c:namespace:: DTV.fe
.. _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
========
.. c:macro:: FE_GET_PROPERTY
``int ioctl(int fd, FE_GET_PROPERTY, struct dtv_properties *argp)``
.. c:macro:: FE_SET_PROPERTY
``int ioctl(int fd, FE_SET_PROPERTY, struct dtv_properties *argp)``
Arguments
=========
``fd``
File descriptor returned by :c:func:`open()`.
``argp``
Pointer to struct :c:type:`dtv_properties`.
Description
===========
All Digital TV 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.
.. note::
At return, the values aren't updated to reflect the actual
parameters used. If the actual parameters are needed, an explicit
call to ``FE_GET_PROPERTY`` is needed.
- ``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 is returned, and the ``errno`` variable is set
appropriately.
Generic error codes are described at the
:ref:`Generic Error Codes <gen-errors>` chapter.
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