title: Map a caps lock key that is mapped to ctrl system wide to Escape just in vim
body: <p>i have mapped my caps lock key to ctrl with the following command under linux:<br>
  <code>
      setxkbmap -option ctrl:nocaps
  </code>
  I really like this mapping and want to keep it, but I also would like to map the caps lock key to Escape when I am inside vim. But when I try to map it with <code>:map &lt;C&gt; &lt;Esc&gt;</code> or similar it  does not seem to work, presumably because the ctrl key is special and needs a second key to to trigger an key event. </p>
  
  <p>Is there any way I can achieve the above?</p>