According to the xset man page, "xset led" is supposed to turn all of the LEDs on the keyboard. And "xset -led" is supposed to turn them all off. But this doesn't happen; only the Scroll Lock LED turns on and off. Not only that, but I cannot get the "xset led nn" command to work except for "xset led 3", which again controls the Scroll Lock LED. I have systems running Fedora Core 3 and Fedora Core 4 test 1 and the xset command gives the same results on both systems.
The "keyboard" and "kbd" drivers in Xorg default to restricting the Caps & Num Lock LED's to being modifiable only by keyboard state change, not by client programs, but allow you to configure this in the xorg.conf if you want to change it. From kbd(7) & keyboard(7): Option "XLeds" "ledlist" makes the keyboard LEDs specified in ledlist avail- able for client use instead of their traditional function (Scroll Lock, Caps Lock and Num Lock). The numbers in the list are in the range 1 to 3. Default: empty list.
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