title: if ( ) < /dev/null
body: <p>I can't wrap my head around this. Why would <code>/dev/null</code> be used as input to an <code>if</code> statement? What is the use of <code>&lt; /dev/null</code> in the following?</p>
  
  <pre><code>if ( $PROG --version ) &lt; /dev/null &gt; /dev/null 2&gt;&amp;1; then
          $PROG
  else
          echo "failed"
          exit 1
  fi
  </code></pre>
  
  <p>I (think) I understand that <code>&gt; /dev/null 2&gt;&amp;1</code> is just used to suppress any output from both <code>stdout</code> and <code>stderr</code>.</p>