title: How to derive current date and time and append at the end of each line that contains 'Hello'
body: <p>I have the following file <code>party.txt</code> that contains something like the following:</p>
  
  <pre><code>Hello Jacky
  Hello Peter
  Bye Johnson
  Hello Willy
  Bye Johnny
  Hello Mary
  Hello Wendy
  </code></pre>
  
  <p>I used the <code>grep hello</code> to capture the contents, but when I use the <code>print date +"%Y-%m-%d'</code> and append to it, I cannot, and I will get many <code>0</code> per line.</p>
  
  <pre><code>cat party.txt | grep Hello | awk '{ print date +"%Y-%m-%d"}'
  </code></pre>
  
  <p>What could I be missing?</p>