code: function done( error ) {
  		if ( clbk.length === 2 ) {
  			if ( error ) {
  				return clbk( error, false );
  			}
  			return clbk( null, true );
  		}
  		if ( error ) {
  			return clbk( false );
  		}
  		return clbk( true );
  	}
docs: FUNCTION: done( error )
  Callback invoked performing a filesystem call.
  
  @private
  @param {Error|Null} error - error object