title: Unable to download and save file from FTP server with Ruby
body: <p>I am trying to download a zip file from an FTP server and save it in a temporary directory:</p>
  
  <pre><code>agent = Net::FTP.new
  agent.connect(host, 21)
  agent.login(user, pass)
  agent.chdir(path)
  agent.passive = true
  file = agent.getbinaryfile(source_file, @file_path)
  file.save!(@file_path)
  </code></pre>
  
  <p>However, it doesn't save the file because it's a String?</p>
  
  <pre><code>NoMethodError: undefined method `save!' for #&lt;String:0x0000000cbc0398&gt;
  </code></pre>
  
  <p>Is there another way to download zip files from an FTP server, or what am I missing?</p>