title: How to Grep for special characters in Linux
body: <p>I wanna grep this $_SESSION["sig"] in Linux, and find out all of files with this variable.  I used </p>
  
  <pre><code>grep -F "$_SESSION["sig"]" *
  fgrep "\$_SESSION["sig"]" *
  fgrep "\$_SESSION\[\"sig\"\]" *
  </code></pre>
  
  <p>but they are not working</p>
  
  <p>How can I fix this? Thank you.</p>