title: Bash printing a help message when no arguments are found using cat
body: <p>What im also supposed to do is if there is no arguments i am supposed to print a "help" message to the standard error device using cat. So far i can understand and get it to work using echo but my task is to do this using cat only. When i try the line <code>cat 2&gt; (help message)</code> it goes to a new line where i can type anything and causes the script to not work correctly at all the only escape being <code>ctrl + z</code>. How can this be done using cat instead of echo? With the stderr message still being printed out as well if thats possible using only cat?</p>
  
  <p><strong>Help Message</strong></p>
  
  <pre><code>Usage: concat FILE ...
  Description: concatenates FILE(s) to standard output separating them with divider -----.
  </code></pre>
  
  <p><strong>Code</strong></p>
  
  <pre><code>#!/bin/bash
  # concat script
  if [[ $@ ]]
  then
          for i in "$@"
          do
           cat "$i" &amp;&amp; echo  "-----"
          done
  exit 0
  else
   cat 2&gt; "Usage: concat FILE ...
  Description: concatenates FILE(s) to standard output separating them with divider -----."
  exit 1
  fi
  </code></pre>