Xmodmap fails to remap modifier keys

Question

When I try to move keys, so that I have CapsLock on escape, Control on CapsLock and Escape on left control, I get the following error:

% xmodmap ~/.Xmodmap
X Error of failed request:  BadValue (integer parameter out of range for operation)
  Major opcode of failed request:  118 (X_SetModifierMapping)
  Value in failed request:  0x17
  Serial number of failed request:  15
  Current serial number in output stream:  15

That is the code that fails:

remove Lock = Caps_Lock

! ESC
keycode 9 = Caps_Lock
add Lock = Caps_Lock
remove Control = Control_L

! CapsLock
keycode 66 = Control_L
add control = Control_L

! Control_R
keycode 37 = Escape

! 2*Meta_L
keycode 148 = Meta_L
add mod1 = Meta_L

If I comment out all lines that start with either add or remove it runs without any errors, but does not do what I want.

Program versions (Gentoo x86 (stable)):

• xorg-server-1.7.6
• xmodmap-1.0.4
• xf86-input-evdev-2.3.2

Xorg.conf:

# nvidia-xconfig: X configuration file generated by nvidia-xconfig
# nvidia-xconfig:  version 1.0  (buildmeister@builder63)  Fri Aug 14 17:54:58 PDT 2009

Section "ServerLayout"
    Identifier     "Layout0"
    Screen      0  "Screen0"
    InputDevice    "Evdev Keyboard" "CoreKeyboard"
    InputDevice    "Evdev Mouse" "CorePointer"
EndSection
Section "Module"
    Disable "dri"
    Disable "dri2"
EndSection

Section "InputDevice"
    Identifier  "Evdev Keyboard"
    Driver      "evdev"
    Option      "Device"     "/dev/input/event2"
    Option      "CoreKeyboard"
    Option      "AutoRepeat" "500 25"
    Option      "XkbRules"   "xorg"
    Option      "XkbModel"   "yahoo"
    Option      "XkbLayout"  "dvp2"
    Option      "XkbOptions"  "grp_led:scroll,grp:rctrl_toggle,compose:rwin,grp:lwin_switch"
EndSection

Section "InputDevice"
   Identifier    "Evdev Mouse"
   Driver        "evdev"
   Option        "CorePointer"
   Option        "Device"                    "/dev/input/event3"
   Option        "Name"                      "Genius Ergo Mouse"
   Option        "HWHEELRelativeAxisButtons" "7 6"
   Option        "WHEELRelativeAxizButtons"  "4 5"
   Option        "SendCoreEvents"            "true"
   Option        "Buttons"                   "11"
EndSection

Section "Files"
    FontPath "/usr/share/fonts/misc"
    FontPath "/usr/share/fonts/Type1"
    FontPath "/usr/share/fonts/100dpi"
    FontPath "/usr/share/fonts/75dpi"

    FontPath "/usr/share/fonts/terminus"
    # FontPath "/usr/share/fonts/intlfonts"

    FontPath "/usr/share/fonts/ttf-bitstream-vera"
    # FontPath "/usr/share/fonts/ttf"
    FontPath "/usr/share/fonts/corefonts"

    FontPath "/usr/share/fonts/paratype"
EndSection

Section "Monitor"
    Identifier     "Monitor0"
    VendorName     "Unknown"
    ModelName      "Unknown"
    HorizSync       28.0 - 33.0
    VertRefresh     43.0 - 72.0
    Option         "DPMS"
EndSection

Section "Device"
    Identifier     "Device0"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
EndSection

Section "Screen"
    Identifier     "Screen0"
    Device         "Device0"
    Monitor        "Monitor0"
    DefaultDepth    24
    SubSection     "Display"
        Depth       24
    EndSubSection
EndSection

#Section "Extensions"
    #Option "Composite" "Disable"
#EndSection
Section "ServerFlags"
    Option         "AutoAddDevices" "false"
    Option         "DontVTSwitch" "false"
    Option         "DontZap" "false"
    Option         "DontZoom"     "true"
EndSection

Everything worked before update.

Answer 1

Most of the time when I get this error it's because I try to assign a key-sym to a modifier but that key-sym is already used for a different modifier. Try running "xmodmap -pm" and verify that the key-syms you are trying to assign to modifiers are not already used.

For example, if Meta_L is already assigned to, say, mod4 then you might get this error if you try to assign Meta_L to mod1 without first removing it from mod4.

Answer 2

According to the Xmodmap Manual, there is at least one key step it appears you have left out. Not only must you "remove" the modifier bit assignments you must also "clear" the keys from the modifier groups.

Yes, it IS confusing, I know!

It also seems that these tasks/commands must be run in a certain order:

1. The removal/clearing of assignments to groups & keys
2. Assign the keysyms to the desired keycodes
3. Add the keysyms to the appropriate modifier groups

I see that this thread has been inactive for a while and it is clearly dead (the OP has resolved or given up on this issue). But hopefully this clarification may help someone else dealing with a similar situation.