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.. 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_get_min_timeout:
.. _lirc_get_max_timeout:

****************************************************
ioctls LIRC_GET_MIN_TIMEOUT and LIRC_GET_MAX_TIMEOUT
****************************************************

Name
====

LIRC_GET_MIN_TIMEOUT / LIRC_GET_MAX_TIMEOUT - Obtain the possible timeout
range for IR receive.

Synopsis
========

.. c:function:: int ioctl( int fd, LIRC_GET_MIN_TIMEOUT, __u32 *timeout)
    :name: LIRC_GET_MIN_TIMEOUT

.. c:function:: int ioctl( int fd, LIRC_GET_MAX_TIMEOUT, __u32 *timeout)
    :name: LIRC_GET_MAX_TIMEOUT

Arguments
=========

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

``timeout``
    Timeout, in microseconds.


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

Some devices have internal timers that can be used to detect when
there's no IR activity for a long time. This can help lircd in
detecting that a IR signal is finished and can speed up the decoding
process. Returns an integer value with the minimum/maximum timeout
that can be set.

.. note::

   Some devices have a fixed timeout, in that case
   both ioctls will return the same value even though the timeout
   cannot be changed via :ref:`LIRC_SET_REC_TIMEOUT`.


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.