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Some references were broken. It was also mentioning LIRC_MODE_RAW, with it is not implemented on current LIRC drivers. So, fix the references. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
63 lines
1.5 KiB
ReStructuredText
63 lines
1.5 KiB
ReStructuredText
.. -*- coding: utf-8; mode: rst -*-
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.. _lirc-read:
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***********
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LIRC read()
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***********
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Name
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====
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lirc-read - Read from a LIRC device
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Synopsis
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========
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.. code-block:: c
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#include <unistd.h>
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.. cpp:function:: ssize_t read( int fd, void *buf, size_t count )
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Arguments
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=========
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``fd``
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File descriptor returned by ``open()``.
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``buf``
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``count``
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Description
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===========
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:ref:`read() <lirc-read>` attempts to read up to ``count`` bytes from file
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descriptor ``fd`` into the buffer starting at ``buf``. If ``count`` is zero,
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:ref:`read() <lirc-read>` returns zero and has no other results. If ``count``
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is greater than ``SSIZE_MAX``, the result is unspecified.
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The lircd userspace daemon reads raw IR data from the LIRC chardev. The
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exact format of the data depends on what modes a driver supports, and
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what mode has been selected. lircd obtains supported modes and sets the
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active mode via the ioctl interface, detailed at :ref:`lirc_ioctl`.
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The generally preferred mode is LIRC_MODE_MODE2, in which packets
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containing an int value describing an IR signal are read from the
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chardev.
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See also
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`http://www.lirc.org/html/technical.html <http://www.lirc.org/html/technical.html>`__
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for more info.
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Return Value
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============
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On success, the number of bytes read is returned. It is not an error if
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this number is smaller than the number of bytes requested, or the amount
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of data required for one frame. On error, -1 is returned, and the ``errno``
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variable is set appropriately.
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