title: how to use echo command to print out content of a text file?
body: <p>I am trying to figure out what is the usage of this command:</p>
  
  <pre><code>echo &lt; a.txt
  </code></pre>
  
  <p>According to text book it should redirect a programs standards input. Now I am redirecting a.txt to echo but instead of printing the content of the file it is printing out one empty line!
  Appreciate if anyone display this behaviour.</p>