---

When xbacklight doesn't want to collaborate

bbacklight is a command line utility, written in the POSIX shell language, created to overcome the problem of the more famous xbacklight which on some devices does not work as it should.
This is why bbacklight was written trying to keep compatibility with xbacklight as much as possible.

Dependencies

• gnu-coreutils or busybox
• curl or wget (optional)

Installation

Prerequisite

$ sudo groupadd bbacklight
$ echo "ACTION==\"add\", SUBSYSTEM==\"backlight\", KERNEL==\"<device>\", RUN+=\"/bin/chgrp bbacklight /sys/class/backlight/%k/brightness\"" | sudo tee -a /etc/udev/rules.d/bbacklight.rules
$ echo "ACTION==\"add\", SUBSYSTEM==\"backlight\", KERNEL==\"<device>\", RUN+=\"/bin/chmod g+w /sys/class/backlight/%k/brightness\"" | sudo tee -a /etc/udev/rules.d/bbacklight.rules
$ sudo usermod -aG bbacklight $USER
$ reboot # or "sudo udevadm control --reload-rules && sudo udevadm trigger"

Where <device> should be replaced with the device you want to use (ex. acpi_video0 or intel_backlight).

Git

$ curl -L "https://git.io/bbacklight" > bbacklight && chmod +x bbacklight
$ sudo mv bbacklight /usr/bin/

Configuration

The program is set by default to use the first entry in the /sys/class/backlight directory.
To change this behavior, edit the program with a text editor, set the DEF_DEVICE variable with an entry/device of your choice (ex.DEF_DEVICE="acpi_video0" or DEF_DEVICE="intel_backlight").
Otherwise you can use the -d <DEVICE> option.

Usage

$ bbacklight -help
Usage: bbacklight <command>
  where <command> are:
  -help
      Show this help text
  -version
      Show version
      And, possibly, if a different version is available on GitHub
  -get [raw]
      Show the current brightness percentage (rounded down)
      If 'raw' is provided, it shows the current brightness value
  -inv <percentage> (w/o % symbol)
      Increase the brightness by a percentage value decided by the user
  -dec <percentage> (w/o % symbol)
      Decrease the brightness by a percentage value decided by the user
  -set <percentage> (w/o % symbol)
      Set the brightness to a percentage value decided by the user
  -d <device>
      Choose which device to change the brightness or request the current value
      The default device is the first entry of dir '/sys/class/backlight'