title: read printf format from a bash var
body: <p>I have a bash script I'm happy with::</p>
  
  <pre><code>$ printf '  Number of xml files: %s\n' `find . -name '*.xml' | wc -l`
  42
  $
  </code></pre>
  
  <p>then the message became longer:</p>
  
  <pre><code>$ printf '  Very long message here about number of xml files: %s\n' `find . -name '*.xml' | wc -l`
  42
  $
  </code></pre>
  
  <p>So I try to put it in a MSG var to stay at 80cols::</p>
  
  <pre><code>$ MSG='  Number of xml files after zip-zip extraction: %s\n'
  $ printf $MSG `find xml_out -name '*.xml' | wc -l`
  </code></pre>
  
  <p>with no success::</p>
  
  <pre><code>$ printf $MSG `find xml_out -name '*.xml' | wc -l`
  Number$
  $ 
  </code></pre>