Section: System Administration Utilities (8)
Updated: Last change: May 2017
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lircd - Decode infrared signals and provide them on a socket.
[options] [config file]
The main task of lircd is to decode the infrared signals and provide
an uniform interface for client applications. Clients can connect to
lircd through a Unix domain socket, by default
/usr/var/run/lirc/lircd. Using this socket they will get the infrared
codes received by lircd and they can send commands to lircd.
The configuration file, by default /usr/etc/lirc/lircd.conf. A relative
path is interpreted from /usr/etc/lirc. The default configuration file
includes all files in /usr/etc/lircd.conf.d.
Each remote which should be decoded by lircd usually requires that a
specific file is used e. g., by copying it to /usr/etc/lirc/lirc.conf.d/.
The format is described in lircd.conf(5). Configuration files could be
found using lirc-setup(1). It's also possible to
generate a config file using irrecord(1)
-d, --device <device>
Select the character device which lircd should read from. The default
is currently /dev/lirc0 on most systems.
Some drivers, including the default devinput driver, supports the
auto device which picks the first usable device found for the actual
When using the devinput driver name=STRING
or phys=STRING can be used to select the device; lircd will
look in /dev/input to find a device with a matching description.
This is useful in case the device name isn't fixed. STRING
may contain the '*' and '?' wildcards and '\' to mark them as literal.
Use mode2 --driver devinput --list-devices to list the
-H, --driver <driver>
The driver to use. Using
lists all available drivers, see DRIVER LOADING below.
- -h, --help
Displays short help message.
- -a, --allow-simulate
Enable the SIMULATE command which can be issued using irsend(1) or
the client API. This will allow simulating arbitrary IR events
from the command line. Use this option with caution because it will give all
users with access to the lircd socket wide control over the system.
E.g., if you have configured your system to shut down by a button press
on your remote control, everybody will be able to shut down
your system from the command line.
-c, --connect [host[:port]][,[host[:port]]]
Connects to other lircd servers that provide a network
socket at the given host and port number (see --listen). The
number of such connections is currently limited to 100.
The connecting lircd instance will receive IR events from the lircd
instance it connects to. To connect to multiple servers, add them as a
comma separated list.
-e, --effective-user <uid>
If started as user root, lircd drops it privileges and runs as user <uid>
after opening files etc.
- -i, --immediate-init
Lircd normally initializes the driver when the first client
connects. If this option is selected, the driver is instead initialized
immediately at start.
-A, --driver-options key:value[|key:value...]
Set one or more options for the driver. The argument is a list of
key:value pairs delimited by '|'. The key can not contain spaces, but
such are allowed in the value part. Certain characters including '#'
and ';' are used as comment markers in the config file and are not
- -Y, --dynamic-codes [EXPERIMENTAL]
Allows use of codes which have been decoded for one remote but
are not defined in lircd.conf. New codes are dynamically
created with a default name. This feature is experimental and subject
to all sorts of changes. It has not ben tested thoroughly.
-l, --listen [[address:]port]]
Let lircd listen for network
connections on the given address/port. The default address is 0.0.0.0,
which means that connections on all network interfaces will be accepted.
The address must be given in dotted numerical form.
Port defaults to 8765.
The listening lircd instance will send all IR events to the connecting
lircd instances without any security checks.
On non-glibc platforms the address:port argument is mandatory, but can be
given as an empty string e. g. --listen= which then defaults
-L, --logfile <logfile path>
Select the lircd daemon log file. logfile is either the string 'syslog'
indicating that syslog(1) should be used or a log file path. The default
is to use syslog.
-D, --loglevel [level]
Determine the amount of logging information. level can be a symbolic
syslog level: 'error','warning, 'info', 'notice' or 'debug'.
lircd also defines three additional levels 'trace', 'trace1' and 'trace2'
which gives even more messages ('trace2' bringing the most).
However, in the log these messages are marked as 'debug'.
On non-glibc platforms the level argument is mandatory, but can be
given as an empty string e. g. --loglevel= which then defaults
The level can also be an integer in the range 3 (almost no messages) to
-O, --options-file <path>
File containing default values for all options. A relative path is
interpreted from current directory. See [FILES] below.
-o, --output <output socket>
Select Unix domain socket, which lircd will write remote key codes to.
The default currently is /usr/var/run/lirc/lircd.
-p, --permission <perm>
Gives the file permission of the output socket if it has to be
created in octal representation. See chmod(1).
If no --permission option is given when the
socket is initially created the default is to give all users read
and write permissions (0666 in octal representation). If
the socket already exists this option has no effect.
-p, --pidfile <path>
Select the lircd daemon pid file, defaults to /usr/var/run/lirc/lircd.pid.
-U --plugindir <path>
Sets the directory from which lircd loads it's
userspace drivers. These are *.so files, by default found as described
under DRIVER LOADING. The argument is a :-separated search path.
-r, --release [suffix]
This option is deprecated and will be removed in an upcoming release. See
lircd-uinput(8) for a replacement.
Enables automatic generation of release events for each button press.
lircd will append the given suffix to the button name for each release
event. If no suffix is given the default suffix is '_EVUP'.
Note the suffix _UP, which was used by
prior to 0.10.0, is used by the linux kernel for other purposes since 4.7.
-R, --repeat-max <limit>
Sets an upper limit to the number of repeats when sending a signal. The
current default is 600. A SEND_START request will repeat the signal this
many times. Also, if the number of repeats in a SEND_ONCE request exceeds
this number, it will be replaced by this number.
SOCKET BROADCAST MESSAGES FORMAT
When decoding a button press or receiving a SIGHUP signal lircd.conf
lircd broadcasts messages to all connected clients.
For each decoded button press a package is made available on the
socket. This is printable data formatted as:
<code> <repeat count> <button name> <remote control name>
0000000000f40bf0 00 KEY_UP ANIMAX
The fields are:
A 16 hexadecimal digits number encoding of the IR signal.
It's usage in applications is deprecated and it should be ignored.
shows how long the user has been holding down a button. The counter
will start at 0 and increment each time a new IR signal has been
is the name of a key defined in the lircd.conf file.
remote control name
is the mandatory name attribute in the lircd.conf config file.
These packets are broadcasted to all clients. The only other situation
when lircd broadcasts to all clients is when it receives the SIGHUP signal
and successfully re-reads its config file. Then it will send a SIGHUP
packet to its clients indicating that its configuration might have changed.
The sighup packet is three lines
SOCKET COMMAND INTERFACE
Applications can also send commands to lircd over the socket interface. The
most common task is sending data, but there are also other commands.
Each command is a single printable line, terminated with a newline. For
each command, lircd replies with a reply package.
SEND_ONCE <remote control> <button name> [repeats]
Tell lircd to send the IR signal associated with the given remote
control and button name, and then repeat
it repeats times.
repeats is a decimal number between 0
The latter can be given as a --repeat-max command line argument to lircd,
and defaults to 600.
If repeats is not specified or is less than the minimum number of
repeats for the selected remote control, the minimum value will be used.
SEND_START <remote control name> <button name>
Tell lircd to start repeating the given button until it receives a
However, the number of repeats is limited to repeat_max. lircd won't
accept any new send commands while it is repeating.
SEND_STOP <remote control name> <button name>
Tell lircd to abort a SEND_START command.
LIST [remote control]
Without arguments lircd replies with a list of all defined remote
Given a remote control argument, lircd replies with a
list of all keys defined in the given remote.
Given a path, lircd will start logging all received data on that file.
The log is printable lines as defined in mode2(1) describing pulse/space
Without a path, current logfile is closed and the logging is stopped.
DRV_OPTION key value
Make lircd invoke the drvctl_func(DRVCTL_SET_OPTION, option) with
option being made up by the parsed key and value.
The return package reflects the outcome of the drvctl_func call.
SIMULATE key data
Given key data, instructs lircd to send this to all
clients i. e., to simulate that this key has been decoded.
The key data must be formatted exactly as the packet described in
[SOCKET BROADCAST MESSAGES FORMAT], notably is the number of digits in
code and repeat count hardcoded.
This command is only accepted if the --allow-simulate command line
option is active.
SET_TRANSMITTERS transmitter mask
Make lircd invoke the drvctl_func(LIRC_SET_TRANSMITTER_MASK, &channels),
where channels is the decoded value of transmitter mask. See
lirc(4) for more information.
Tell lircd to send a version packet response.
The protocol guarantees that broadcasted messages won't interfere with
reply packets. But broadcasts may appear at any point between packets.
The only exception are SIGHUP packages. These may appear just after
you have sent a command to lircd, so you have to make sure you don't
confuse them with replies.
The format of the reply packet is
n lines of data]
If the command was successful, data is only sent for the commands that
return some information. Note that a packet containing 0 lines of data
can be a valid reply.
RUNNING AS REGULAR USER
has been running as root since accessing kernel devices like
by default requires root privileges.
However, running a long-running service like this is a major security
The lirc distribution contains example udev rules which makes
, USB and serial devices accessible by the
Using these rules, it is possible to run
as a regular user and group such as
Main config file, see lircd.conf(5).
The options file. lircd handles the values under the [lircd] section
in this file. The location can be changed using the -O/--options-file
command-line option or using the environment variable LIRC_OPTIONS_PATH.
The values here are used as defaults for any option not present on
Options file path, see FILES.
Plugin load path, se DRIVER LOADING.
If set, enables debugging in early stages when the
option is yet not parsed.
Drivers are loaded dynamically. This is done from a traditional *ux
':'-separated path where each component in the path is searched (leading
part first, trailing last).
The path used for this is determined by (falling priority):
The --plugindir option.
The 'plugindir' entry in the [lircd] section of the lirc_options.conf file.
The environment variable LIRC_PLUGINDIR.
A hardcoded default (/usr/lib/lirc/plugins).
On receiving SIGHUP lircd re-reads the lircd.conf configuration file
(but not lirc_options.conf) and adjusts itself if the file has changed.
On receiving SIGUSR1 lircd makes a clean exit.
is a daemon. You should start it in some init script
depending on your system. Besides the systemd setup which is
installed by default there are also example scripts for other distros
and init systems in the contrib directory.
This document was created by
using the manual pages.
Time: 20:22:15 GMT, June 09, 2017