title: ubuntu : how to clear $SHELL history
body: <pre><code>No command 'exprt' found, did you mean:
   Command 'expr' from package 'coreutils' (main)
  exprt: command not found
  </code></pre>
  
  <p>i got this msg everytime i open the terminal. 'exprt' is my typo error during installation. I've tried </p>
  
  <pre><code># history -c
  # history -cw
  </code></pre>
  
  <p>but it still can't get rid of this problem, especially when</p>
  
  <pre><code># exec $SHELL
  </code></pre>
  
  <p>it prompt the same error as well</p>
  
  <p>any solution? I'm newbie to ubuntu...</p>