title: delete all files in a folder at FTP using ftp batch script
body: <p>Have batch script as follows:</p>
  
  <pre><code>&gt;&gt;ftp.txt open ftp.site.com
  &gt;&gt;ftp.txt username
  &gt;&gt;ftp.txt password
  &gt;&gt;ftp.txt directoryname
  &gt;&gt;ftp.txt quit
  ftp -s ftp.txt
  </code></pre>
  
  <p>How can I delete all files in folder 'directoryname'?  </p>