CI_Session_driver::_fail PHP Method

_fail() protected method

Drivers other than the 'files' one don't (need to) use the session.save_path INI setting, but that leads to confusing error messages emitted by PHP when open() or write() fail, as the message contains session.save_path ... To work around the problem, the drivers will call this method so that the INI is set just in time for the error message to be properly generated.
protected _fail ( ) : mixed
return mixed
    protected function _fail()
    {
        ini_set('session.save_path', config_item('sess_save_path'));
        return $this->_failure;
    }