lib/magento/Archive/Helper/File.php
protected function _open($mode)
    {
        $this->_fileHandler = @fopen($this->_filePath, $mode);

        if (false === $this->_fileHandler) {
            throw new Mage_Exception('Failed to open file ' . $this->_filePath);
        }
    }
protected function _open($mode)
    {
        $this->_fileHandler = @fopen($this->_filePath, $mode);

        if (false === $this->_fileHandler) {
            throw new Mage_Exception('Failed to open file ' . $this->_filePath);
        }
    }
protected function _open ( $ mode ) { $ this -> _fileHandler = @ fopen ( $ this -> _filePath , $ mode ) ; if ( false === $ this -> _fileHandler ) { throw new Mage_Exception ( 'Failed to open file ' . $ this -> _filePath ) ; } }
Implementation of file opening

@param string $mode
@throws Mage_Exception
Implementation of file opening