title: Why are RackMultipart* files persisting in my Rails /tmp directory?
body: <p>I'm using Paperclip (2.3) to handle image uploads on a Rails 3.0.3 app running on Ubuntu. Paperclip is handling the uploads as advertised BUT the RackMultipart* files that are created in the application's /tmp folder persist -- that is, they simply accumulate rather than deleting themselves. I realize that I could use tmpreaper to delete old tmpfiles but I'd really like to find a more elegant (and scalable) solution.</p>
  
  <p>I had a previous issue with temp files (i.e. RackMultipart* files) accumulating in the Rails app's root directory (instead of in /tmp). I resolved this by explicitly setting the temp path in my environment.rb file like so:</p>
  
  <pre><code>ENV['TMPDIR'] = Rails.root.join('tmp')
  </code></pre>
  
  <p>Is there another environment variable that needs to be set to make sure that the tempfiles are handled properly -- i.e. deleted once they've been saved in the model? I'm not sure if this is a problem with Paperclip or my Rails setup.</p>
  
  <p>I've searched high and low but have made little progress on this. I'd be grateful for any leads.</p>
  
  <p>Sincere thanks.</p>
  
  <p>PS - I'm using currently using S3 for storage. This doesn't seem to be tied to the problem though -- I had the same problem when I was storing the files locally.</p>