title: How to insert a text in middle of nth line of file
body: <p>I am trying to insert a pipe symbol in between nth line of a file. Like the one present in the output of diff command. </p>
  
  <p>Do not want to use VI editor.</p>
  
  <p>For example,desired line is 2nd line of the file:</p>
  
  <pre><code>cat filename
  
  Hi            Hi
  Hello         Hello
  This          This
  is            Is
  it            it
  </code></pre>
  
  <p>desired output:</p>
  
  <p>cat filename</p>
  
  <pre><code>Hi            Hi
  Hello    |     Hello
  This          This
  is            Is
  it            it
  </code></pre>