Trying to understand XKB and how to customize keyboard mappings, specially for modifiers.A little experiment on disabling modifiers, leads to an unexpected result:(1) Modifier maps before$ xmodmap -pmxmodmap:  up to 4 keys per modifier, (keycodes in parentheses):shift       Shift_L (0x32),  Shift_R (0x3e)lock        Caps_Lock (0x42)control     Control_L (0x25),  Control_R (0x69)mod1        Alt_L (0x40),  Alt_R (0x6c),  Meta_L (0xcd)mod2        Num_Lock (0x4d)mod3      mod4        Super_L (0x85),  Super_R (0x86),  Super_L (0xce),  Hyper_L (0xcf)mod5        ISO_Level3_Shift (0x5c),  Mode_switch (0xcb)(2) Clear lock modifier$ xmodmap -e 'clear Lock'(3) Cleared ok$  xmodmap -pmxmodmap:  up to 4 keys per modifier, (keycodes in parentheses):shift       Shift_L (0x32),  Shift_R (0x3e)lock      control     Control_L (0x25),  Control_R (0x69)mod1        Alt_L (0x40),  Alt_R (0x6c),  Meta_L (0xcd)mod2        Num_Lock (0x4d)mod3      mod4        Super_L (0x85),  Super_R (0x86),  Super_L (0xce),  Hyper_L (0xcf)mod5        ISO_Level3_Shift (0x5c),  Mode_switch (0xcb)I expected to disable CapsLock from setting the lock state, but it does't.It works as usual, and using xev to see the key press events, I see that the lock flag still changes (state 0x0 when CapsLock is off, state 0x2 when on).What is actually the clear command doing?How can I detach keys(keycodes) to disable their function as modifiers?
xmodmap clear modifier not working
keyboard shortcuts;xkb
Actually, CapsLock functionality is bound to keysym value of pressed key. To see mapping of keycodes to keysyms execute xmodmap -pke. The mapping of CapsLock (keycode 66) should be (| grep 'keycode  66'): keycode  66 = Caps_Lock NoSymbol Caps_LockYou may play around a bit with xev. Read more at ArchWiki: Xmodmap#Introduction.How can I detach keys(keycodes) to disable their function as  modifiers?You need to change mapping of CapsLock. To disable CapsLock, you need to unmap it:xmodmap -e 'keycode  66 = NoSymbol NoSymbol NoSymbol'To enable CapsLock, you need to map it again to default values:xmodmap -e 'keycode  66 = Caps_Lock NoSymbol Caps_Lock'What is actually the clear command doing?It clears mapping of a modifier, not mapping of keycodes. More at ArchWiki: Xmodmap#Modifier_keys