title: while condition in shell script with -h in condition checking
body: <p>I was trying to understand the <code>karaf.sh</code> in <code>jboss-fuse</code> <code>esb</code> shell scripts. I am unable to understand  below line.</p>
  
  <pre><code>while [ -h "${dst}" ] ;
  </code></pre>
  
  <p>Can anyone let me know <strong>what -h</strong> will do in the condition checking statement?</p>