LIGHT(1) User’s Reference Manual LIGHT(1)
NAME
light — a program to control backlight controllers
SYNOPSIS
light [OPTIONS] [VALUE]
DESCRIPTION
light is a program to control backlight display and keyboard controllers under GNU/Linux.
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Operates independently of X (X-Window)
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Can automatically figure out the best controller to use, making full use of the underlying hardware
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Supports a minimum cap on the brightness value, as some controllers set the display to be pitch black at a vaĺue of 0 (or higher)
COMMANDS
The following unique commands are supported:
−H, −h
Show help text and exit
−V
Show program version and exit
−L
List available devices
−A
Increase brightness by value
−U
Decrease brightness by value
−S
Set brightness to value
−G
Get brightness, default
−N
Set minimum brightness to value
−P
Get minimum brightness
−O
Save current brightness
−I
Restore previously saved brightness
OPTIONS
The behavior of the above commands can be modified using these options:
−r
Interpret input and output values in raw mode
−s PATH
Specify device target path. Use −L to list available devices
−v LEVEL
Set verbosity level, by default light only outputs read values:
0:
Read values
1:
Read values, Errors
2:
Read values, Errors, Warnings
3:
Read values, Errors, Warnings, Notices
FILES
When run in its classic SUID root mode light caches settings and current brightness in /etc/light. In its non-privileged mode of operation the ~/.cache/light directory is used instead.
AUTHORS
Copyright © 2012-2018 Fredrik Haikarainen
This is free software, see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE
GNU/Linux August 4, 2018 GNU/Linux