Swap the Ctrl and the Windows key under ubuntu

sawp_keys

I'm so used to Mac key mapping that I want to use the windows key as the ctrl, and the ctrl as the windows key.

I found a very useful link here:
http://stackoverflow.com/questions/21845209/remap-ctrl-alt-super-keys-in-ubuntu-13-10

first run this to generate the keymap
  xmodmap -pke > ~/.Xmodmap.

open .Xmodmap file, add these at the beginning:
  clear control
  clear mod1
  clear mod4

and these at the end:
  add control = Control_L Control_R
  add mod1 = Alt_L Alt_R
  add mod4 = Super_L Super_R

swap the key codes for ctrl and windows.

save the file and run:
    xmodmap ~/.Xmodmap

Swap control and alt

!
! based on: http://www.emacswiki.org/emacs/SwapControlAltAndCapsLock#toc8
!

!----------------------------------------------------------
! Swap Control and Alt keys, both sides
!----------------------------------------------------------

! First clear all modifiers & control
clear control
clear mod1
clear mod4

! Swap Control_L and Alt_L
keycode 64 = Control_L
keycode 37 = Alt_L Meta_L

! Menu becomes Alt_R Meta_R (AltGr)
keycode 135 = Alt_R Meta_R

! Define Control_R and Alt_R similar to Control_L and Alt_L
keycode 108 = Control_L
keycode 105 = Alt_L Meta_L

! We need to set keycodes first, as some programs (emacs!) read
! the key names and seem to ignore what's below.
add mod1 = Alt_L Alt_R Meta_L Meta_R
add mod4 = Super_L Super_R
add control = Control_L Control_R

!------------------------------------------
! Caps_Lock becomes an additional BackSpace
!------------------------------------------
remove lock = Caps_Lock
keysym Caps_Lock = BackSpace