>>>> $ nano /etc/default/keyboard
>>>> XKBMODEL="pc105"
>>>> XKBLAYOUT="us"
>>>> XKBVARIANT=""
>>>> XKBOPTIONS="compose:ralt"
>>>> BACKSPACE="guess"
>>>>
>>>>
>>>> $ xmodmap -pke | grep Alt
>>>> keycode 64 = Alt_L Meta_L Alt_L Meta_L
>>>>
>>>> but no Alt_R or ralt. I could use right Windows but do not see it
>>>> in the map either.
>>>>
>>>> When pressing AltGr on my (not Dell) keyboard, xev returns:
>>>>
>>>> ~~~
>>>> KeyRelease event, serial 48, synthetic NO, window 0x2800001,
>>>> root 0x528, subw 0x2800002, time 37381333, (41,47), root:(792,492),
>>>> state 0x90, keycode 108 (keysym 0xfe03, ISO_Level3_Shift), same_screen
>>>> YES, XKeysymToKeycode returns keycode: 92
>>>> XLookupString gives 0 bytes:
>>>> XFilterEvent returns: False
>>>> ~~~
>>>>
>>>> So... ISO_Level3_Shift also seems to be synonymous with AltGr...
>>>>
>>>>
That seems to be consistent with what I find on my keyboard also.
/etc/default/keyboard:
XKBMODEL="pc105"
XKBLAYOUT="us"
XKBVARIANT=""
XKBOPTIONS=""
BACKSPACE="guess"
$ xmodmap -pke | grep Alt
keycode 64 = Alt_L Meta_L Alt_L Meta_L Alt_L Meta_L
keycode 108 = Alt_R Meta_R ISO_Level3_Shift NoSymbol ISO_Level3_Shift
keycode 204 = NoSymbol Alt_L NoSymbol Alt_L NoSymbol Alt_L