source/Setup/Session.php
protected function _validateSession()
    {
        if ($this->getIsNewSession() === true) {
            $this->setSessionParam('setup_session', true);
        } elseif ($this->getSessionParam('setup_session') !== true) {
            $sNewSid = $this->_getNewSessionID();
            session_write_close();

            session_id($sNewSid);
            session_start();
            $this->setSessionParam('setup_session', true);
        }

        return session_id();
    }
protected function _validateSession()
    {
        if ($this->getIsNewSession() === true) {
            $this->setSessionParam('setup_session', true);
        } elseif ($this->getSessionParam('setup_session') !== true) {
            $sNewSid = $this->_getNewSessionID();
            session_write_close();

            session_id($sNewSid);
            session_start();
            $this->setSessionParam('setup_session', true);
        }

        return session_id();
    }
protected function _validateSession ( ) { if ( $ this -> getIsNewSession ( ) === true ) { $ this -> setSessionParam ( 'setup_session' , true ) ; } elseif ( $ this -> getSessionParam ( 'setup_session' ) !== true ) { $ sNewSid = $ this -> _getNewSessionID ( ) ; session_write_close ( ) ; session_id ( $ sNewSid ) ; session_start ( ) ; $ this -> setSessionParam ( 'setup_session' , true ) ; } return session_id ( ) ; }
Validate if session is started by setup script, if not, generate new session.

@return string Session ID
Validate if session is started by setup script if not generate new session .