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I have a Samsung np700z5a and have managed to get most features working but would love to get the keyboard backlight keys working.

I have tried several methods including through the terminal. I have discovered that this works through the terminal:

echo 6 > /sys/class/leds/samsung\:\:kbd_backlight/brightness

after an

sudo su

(but not, sudo echo 6 > /sys/class/leds/samsung\:\:kbd_backlight/brightness where I get permissions denied).

I have tried running this in AutoKey as this script:

sudo su
echo 3 > /sys/class/leds/samsung\:\:kbd_backlight/brightness

and assigned it to some keys in AutoKey but it did not work.

I noticed that when I tried to assign it to the Fn + F9 key, this key and FN + F10 where not recognised at all (these are the keys designated to turn the keyboard backlight up and down in a windows install) so I assigned it to SUPER + - instead. As I said it does not work.

Please help.

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su <user> -c <command>

You will still have to provide the password, though.

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not exactly sure what that means... But I typed: !/bin/bash su SIMON-700Z5A -c echo 3 > /sys/class/leds/samsung\:\:kbd_backlight/brightness , then assigned a key combination in auto hotkey. no dice. – user181401 Aug 7 '13 at 6:12
Didn't it prompt you for a password? – David Aug 7 '13 at 7:50
didn't work at all. is what I wrote above what you were suggesting I write? not sure if that is my user name, i think it is the pc name. I just tried again and wrote in the terminal: su simon -c echo 6 > /sys/class/leds/samsung\:\:kbd_backlight/brightness but it says permission denied. – user181401 Aug 7 '13 at 9:07
When you open a terminal (Ctrl+Alt+T), it says <user>@<host>:~# at the beginning of the line. <user> is your username, <host> is the name of your computer. – David Aug 7 '13 at 9:40
As you have to do this as root, you should probably use su root -c 'echo "6" > /sys/class/leds/samsung\:\:kbd_backlight/brightness'. :) Also, be carefully with that >. A single > overwrites the file, while >> attaches the output to the end of it. – David Aug 7 '13 at 9:42

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