title: insert the contents of a file to another (in a specific line of the file that is sent)-BASH/LINUX
body: <p>I tried doing it with <code>cat</code> and then after I type the second file I added <code>| head -$line | tail -1</code> but it doesn't work because it performs <code>cat</code> first.</p>
  
  <p>Any ideas? I need to do it with <code>cat</code> or something else.</p>