title: How do positional arguments like "1$" work with printf()?
body: <p>By <code>man</code> I find </p>
  
  <pre><code>               printf("%*d", width, num);
  </code></pre>
  
  <p>and</p>
  
  <pre><code>               printf("%2$*1$d", width, num);
  </code></pre>
  
  <p>are equivalent.</p>
  
  <p>But IMO the second style should be the same as:</p>
  
  <pre><code>               printf("%*d", num, width);
  </code></pre>
  
  <p>However via testing it seems <code>man</code> is right; why?</p>