.. Permission is granted to copy, distribute and/or modify this
.. document under the terms of the GNU Free Documentation License,
.. Version 1.1 or any later version published by the Free Software
.. Foundation, with no Invariant Sections, no Front-Cover Texts
.. and no Back-Cover Texts. A copy of the license is included at
.. Documentation/userspace-api/media/fdl-appendix.rst.
..
.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections

.. _lirc_set_rec_carrier:

**************************
ioctl LIRC_SET_REC_CARRIER
**************************

Name
====

LIRC_SET_REC_CARRIER - Set carrier used to modulate IR receive.


Synopsis
========

.. c:function:: int ioctl( int fd, LIRC_SET_REC_CARRIER, __u32 *frequency )
    :name: LIRC_SET_REC_CARRIER

Arguments
=========

``fd``
    File descriptor returned by open().

``frequency``
    Frequency of the carrier that modulates PWM data, in Hz.

Description
===========

Set receive carrier used to modulate IR PWM pulses and spaces.

.. note::

   If called together with :ref:`LIRC_SET_REC_CARRIER_RANGE`, this ioctl
   sets the upper bound frequency that will be recognized by 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.
