.Xmodmap

! CapsLock to Control_L
clear      lock
clear   control
keycode      66 = Control_L
add     control = Control_L Control_R


! left Alt & right Alt
keycode  64 = Meta_L
keycode 108 = Meta_R
! left Win & right Win
keycode 133 = Alt_L
keycode 134 = Alt_R

clear      mod1
clear      mod4
add        mod1 = Alt_L Alt_R
add        mod4 = Meta_L Meta_R

! default
! 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)