code: function onBeforeUpload(up, file) {
  		// Generate unique target filenames
  		if (up.settings.unique_names) {
  			var matches = file.name.match(/\.([^.]+)$/), ext = "part";
  			if (matches) {
  				ext = matches[1];
  			}
  			file.target_name = file.id + '.' + ext;
  		}
  	}
docs: Internal event handlers