light

Light 0.9

Copyright (C) 2012 - 2014, 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

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Description:

"Light"  is  a program  to control backlight controllers  under GNU/Linux,
it is the successor of lightscript, which was a bash script with the  same
purpose, and tries to maintain the same functionality.


Features:

  * Works excellent where other software has been proven to be unusable or
    problematic, thanks to how it operates internally and to the fact that
    it does not rely on xorg.

  * Can automatically figure out the best controller to use,   making full
    use of underlying hardware.

  * Possibility to set a minimum brightness value, as some controllers set
    the screen to be pitch black at a vaĺue of 0 (or higher).


Installation:
  
  If you run ArchLinux, there is a package in the AUR called light.

  1) Install neccessary build tools (gcc, make etc.)

  2) Type `make`

  3) Run makeexec.sh as root to give regular users the ability to run the
     program with root permissions.

  4) Copy/create a symbolic link to the executable to /usr/bin

  5) Enjoy!


Usage:

  This application has 4 different operation modes, which are:

    -G:   Get, which reads/gets brightness/data from controllers/files
    -S:   Set, whichs writes/sets brightness/data to controllers/files
    -A:   Add, does like -S but instead adds the value
    -U:   Subtract, does like -S but instead subtracts the value

  When used by themselves   operate on the brightness of a controller that
  is selected automatically. S, A and U needs another argument,   which is
  the value to set/add/subtract.   This can be specified either in percent
  or in raw values,  but remember to specify the value mode if you want to
  write raw values.

  The value modes are set with -p for percent (default), and -r for raw.

  As you can not only read/write the brightness of controllers,    you may
  also specify a target to read/write from/to:

    -b:   Current brightness of selected controller
    -m:   Maximum brightness of selected controller
    -c:   Minimum brightness (cap) of selected controller

  Finally, you can either use the built-in controller selection to get the
  controller with the maximum precision,   or you can specify one manually
  with the -s flag. The -a flag will force automatic mode and is default.

  NOTE:
  This application will only print errors if you are using it incorrectly.
  If something goes wrong, and you can't figure out why,   try setting the
  verbosity flag:

    -v 0: No debug output
    -v 1: Errors
    -v 2: Errors, warnings
    -v 3: Errors, warnings, notices

  Examples:

    * Get the current brightness in percent
    
      light -G

    * Increase brightness by 5 percent

      light -A 5

    * Set the minimum cap to 2 in raw value on the acpi_video0 controller:

      light -Scrs "acpi_video0" 2