xfpm-power-backlight-helper -V (return code: 3)
No valid option was specified
xfpm-power-backlight-helper --help (return code: 0)
Usage:
xfpm-power-backlight-helper [OPTION?]
XFCE Power Manager Backlight Helper
Help Options:
-h, --help Show help options
Application Options:
--set-brightness Set the current brightness
--get-brightness Get the current brightness
--get-max-brightness Get the number of brightness levels supported
--set-brightness-switch Enable or disable ACPI video brightness switch handling
--get-brightness-switch Get the current setting of the ACPI video brightness switch handling