title: Removing text using grep
body: <p>i am trying to remove a line that contains a particular pattern in a text file.  i have the following code which does not work</p>
  
  <pre><code>`grep -v "$varName" config.txt`
  </code></pre>
  
  <p>can anyone tell me how i can make it work properly, i want to make it work using grep and not sed</p>