title: How to reset all environment variables?
body: <p>I want to do :</p>
  
  <pre><code>env | egrep -o '^\w+=' | unset
  </code></pre>
  
  <p>The problem is that :</p>
  
  <pre><code>env | egrep -o '^\w+='
  </code></pre>
  
  <p>prints things like (notice the <em>equal</em> sign) :</p>
  
  <blockquote>
    <p>XDG_VTNR=
    LC_PAPER=
    SSH_AGENT_PID=
    KDE_MULTIHEAD=
    LC_ADDRESS=
    XDG_SESSION_ID=</p>
  </blockquote>
  
  <p>How do I extract just the variable names so I can unset them? </p>