Klaus Knopper answers your Linux questions
Ask Klaus
Controlling brightness, forensic mode, and proprietary Broadcom WiFi drivers.

Controlling Brightness
On my laptop, the function key combinations that are supposed to change the display's brightness are not working with Linux. Is special software necessary in order to activate those function keys?
Most manufacturers of notebooks use a non-standard keyboard assignment for brightness, WiFi enable/disable, and so on – "non-standard" meaning that there really isn't much of a standard keycode available for the extra functionality. Proprietary operating systems use "drivers" to map extended keyboard events to certain actions, as is done similarly in most Linux distributions using the ACPI daemon with vendor-specific configuration files in /etc/acpi/events
and /etc/acpi/actions
provided by packages such as eeepc-acpi-scripts and acpi-support (which contain known mappings for different notebook brands). Finding the correct settings and writing your own scripts for handling events can be a very complex task, but in some cases, you have an easier way to solve this problem.
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