title: Exporting custom UTI results in UIDocumentInteractionController error 513 "Unable to link file"
body: <p>I have an application that currently accepts incoming files via UIDocumentInteractionController file types, but I'd also like to export a custom UTI to allow other applications to share <em>only</em> to my app if they  prefer (as opposed to all apps that support incoming files of the same type). Basically I am trying to mimic what Instagram does (<a href="http://instagram.com/developer/iphone-hooks/" rel="nofollow">http://instagram.com/developer/iphone-hooks/</a>).</p>
  
  <p>While setting the UTI on the <code>UIDocumentInteractionController</code> <em>does</em> result in only my application being shown to the user, it also results in the following error. The error does not occur if the <code>UIDocumentInteractionController</code> UTI property is not set:</p>
  
  <pre><code>2013-07-15 10:56:02.476 Example[1117:907] Unable to link file://localhost/var/mobile/Applications/55C3F66E-725D-487C-B538-30139C685101/Example.app/photo.png 
  to file://localhost/private/var/mobile/Applications/55C3F66E-725D-487C-B538-30139C685101/tmp/8C6C5225-6582-406C-83CD-BC5A92B91D09/photo.iracephoto. 
  Error: The operation couldn’t be completed. (Cocoa error 513.)
  </code></pre>
  
  <p>Here is the UTI export in my Info.plist file:</p>
  
  <pre><code>&lt;key&gt;UTExportedTypeDeclarations&lt;/key&gt;
  &lt;array&gt;
      &lt;dict&gt;
          &lt;key&gt;UTTypeIdentifier&lt;/key&gt;
          &lt;string&gt;me.irace.photo&lt;/string&gt;
          &lt;key&gt;UTTypeTagSpecification&lt;/key&gt;
          &lt;dict&gt;
              &lt;key&gt;public.filename-extension&lt;/key&gt;
              &lt;string&gt;iracephoto&lt;/string&gt;
          &lt;/dict&gt;
      &lt;/dict&gt;
  &lt;/array&gt;
  </code></pre>