xmode2 - Show the pulse/space length of infrared signals
xmode2 [
options]
The main purpose of
xmode2 is to check operation of your home-brew LIRC
receiver hardware and to see the IR waveform of the remote controller without
an expensive oscilloscope. Very useful for debugging. Of course this program
won't work with hardware that decodes the signals itself like e.g. TV cards or
the Irman i. e., it only works with LIRC_MODE_MODE2 type drivers.
xmode2 prints a simple graphics display of the pulse/space lengths. It
accepts a few commands including time base changes; see the xmode2 -h output.
lirc-lsplugins(1) allows checking if a driver is a LIRC_MODE2 type one.
-
-h --help
- display usage summary
-
-v --version
- display version
-
-d --device=device
- read from given device
-
-H --driver=driver
- use given driver
-
-m --mode
- enable alternative display mode
-
-r --raw
- access device directly
In many cases xmode2 needs to run as root to access devices not available to
regular users. On the other hand, running as root creates problems such as log
files owned by root, security concerns etc.
In order to cope with this, xmode2 by default drops root privileges after
opening the input device. This support is based on that root permissions are
acquired using
sudo(1) e. g., using
$ sudo xmode2 --driver default --device /dev/lirc0
If not using sudo, the same behaviour could be accomplished using the SUDO_USER
environment variable e. g.,
# SUDO_USER=$LOGNAME xmode2 --raw /dev/lirc0
The --keep-root option will make xmode2 keep it's root privileges for the
complete run.
Drivers are loaded dynamically. The search 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 (usually /usr/lib[64]/lirc/plugins).
- ~/.cache/xmode2.log
- Debug output. Setting the XDG_CACHE_HOME environment
variable relocates this file to $XDG_CACHE_HOME/mode2.log
mode2(1)
lirc-lsplugins(1)
The documentation for
lirc is maintained as html pages. They are located
under html/ in the documentation directory.