title: Bash: duplicate + rename folder
body: <p>Suppose I have a folder named <code>my_folder_old</code> in <code>/path/to/folder</code>, how can I create a duplicate named <code>my_folder_new</code> in the same directory?</p>
  
  <p><strong>EDIT</strong></p>
  
  <p>Moreover if <code>my_folder_new</code> already exists, <code>my_folder_old</code> is created inside the first and not substituted. Why is this happening? </p>