title: fs.mkdirSync returns with 'undefined'
body: <p>I am attempting to create a directory and use that directory as a variable to extract files from zip/rar files.  </p>
  
  <p>the bit of code that causes an error is here...</p>
  
  <pre><code>   var fileZip = fileName.replace(/^.*[\\\/]/, ''); 
     // Removes full path to get 'file.zip'
     console.log(fileZip);
     var tempFolder = fs.mkdirSync('./app/cache/' + fileZip); 
     // tempFolder Variable for loaded comic
     console.log('CREATE: ' + tempFolder + ' created, line 26');
  </code></pre>
  
  <p>console.log returns with <code>CREATE: undefined created, line 26</code>.  What is going wrong?  The directory is created where I want it to be, but it isn't being saved as the variable.  </p>
  
  <p>Is it possible that since some file names have spaces (ie <code>file name.zip</code>) that is causing the problem?</p>