title: Twitter Bootstrap - less.app compile error: "EISDIR illegal operation on a directory" when saving
body: <p>I'm trying to get my head around the less css processor for the first time but receive the following error when trying to save any of the Twitter Bootstrap .less files using less.app:</p>
  
  <p><strong>Error: EISDIR illegal operation on a directory: '/path/to/less/output/directory'</strong></p>
  
  <p>I have an output directory set on the bootstrap.less file only - is this a permissions error maybe?</p>
  
  <p>Sorry if this is easy - any pointers in the right direction would be much appreciated.</p>
  
  <p>Cheers</p>
  
  <p>Ben</p>