title: I need to insert text to a file with quotes using sed
body: <p>Hi Stackoverflow users,</p>
  
  <p>Normally I can use sed pretty wel (often need a few tries). However I am having issues with adding the text below at the end of the file:</p>
  
  <pre><code>&lt;linebreak/empty line here&gt;
  [extensions]
  blacklist = "google-authenticator"
  </code></pre>
  
  <p>Into a file called: /usr/local/psa/admin/conf/panel.ini</p>
  
  <p>To make things "more" complicated, I also use the command in OpenVZ automation. Like this:</p>
  
  <pre><code>vzctl exec $VEID 'sed XX "VALUE FROM ABOVE" /usr/local/psa/admin/conf/panel.ini'
  </code></pre>
  
  <p>Can someone provide some help and/or direct me in the right direction?</p>
  
  <p>Obviously I tried a few things, but I think I am having issues with the extra quotes in the text I am trying to add.</p>
  
  <p>Errors are always something like this:</p>
  
  <ul>
  <li>expression #1, char 89: unterminated address regex</li>
  <li>expression #1, char 91: unterminated address regex</li>
  <li>expression #1, char 53: unterminated address regex</li>
  </ul>
  
  <p>So I am doing something wrong and I have no clue how to correctly add the above. Preferably with a line-break in front.</p>
  
  <p>I hope I explained the issue correctly. Thanks in advance for your assistance.</p>
  
  <p>//Edit</p>
  
  <p>All I need is a solution to add the following text:</p>
  
  <pre><code>&lt;linebreak/empty line here&gt;
  [extensions]
  blacklist = "google-authenticator"
  </code></pre>
  
  <p>by using sed. </p>
  
  <p>So I can apply it to my script which creates an OpenVZ container (automated) like: vzctl exec $VEID 'possible sed solution here' /file-name</p>
  
  <p>Sorry if I wasn't clear before.</p>