code: public function fopen($strFile, $strMode)
  	{
  		$this->validate($strFile);
  
  		return fopen($this->strRootDir . '/' . $strFile, $strMode);
  	}
docs: Open a file and return the handle
  
  @param string $strFile The file name
  @param string $strMode The operation mode
  
  @return resource The file handle