Keyboard LED's behavior when more than one keyboard is connected
by Sunshine Glimmer from LinuxQuestions.org on (#5DYHX)
Suppose, you have a computer, which does not have any specific nonstandard settings (such as multiseat).
If two or more keyboards are attached to the same machine (laptop with ext keyboard is common usecase), while the input is focused on a text entry (browser text area on a forum, text editor, terminal emulator or TTY), and you press one of keys which normally both change input mode and have a LED, indicating the current input mode, such as: Caps Lock, Num Lock, Scroll Lock (and others on exotic keyboards), then what will the system do:
a) Input mode is changed for all keyboards, LED is toggled for all keyboards simultaneously.
b) Input mode and LED state are changed only for keyboard, where key is pressed, other keyboard retain their respective input mode and LED states
c) Input mode is changed for all keyboards, however LED is toggled only on the keyboard, where the key was pressed.
Obviously, a and b are sane behaviors, since the input mode is always consistent with LED state, indicating the current input mode. However c is an erroneous behavior, since LED might indicate different input mode to what is actually active (for example, when you type, you get ALL CAPS, but CapsLed is off, or vice versa).
Yet, I think in Linux I experience exactly the erroneous (c) behavior, so I was wondering, is there some setting in the kernel configuration options, or xorg.conf which can fix this behavior to (a) or (b)?
I have not tried this on other operating systems yet. So can you tell me how they behave, if you have time and resources to test?
If two or more keyboards are attached to the same machine (laptop with ext keyboard is common usecase), while the input is focused on a text entry (browser text area on a forum, text editor, terminal emulator or TTY), and you press one of keys which normally both change input mode and have a LED, indicating the current input mode, such as: Caps Lock, Num Lock, Scroll Lock (and others on exotic keyboards), then what will the system do:
a) Input mode is changed for all keyboards, LED is toggled for all keyboards simultaneously.
b) Input mode and LED state are changed only for keyboard, where key is pressed, other keyboard retain their respective input mode and LED states
c) Input mode is changed for all keyboards, however LED is toggled only on the keyboard, where the key was pressed.
Obviously, a and b are sane behaviors, since the input mode is always consistent with LED state, indicating the current input mode. However c is an erroneous behavior, since LED might indicate different input mode to what is actually active (for example, when you type, you get ALL CAPS, but CapsLed is off, or vice versa).
Yet, I think in Linux I experience exactly the erroneous (c) behavior, so I was wondering, is there some setting in the kernel configuration options, or xorg.conf which can fix this behavior to (a) or (b)?
I have not tried this on other operating systems yet. So can you tell me how they behave, if you have time and resources to test?