大神在吗？PHP关于session跟cookie的修改看不懂啊

/**<br> * session管理函数<br> * @param string|array $name session名称 如果为数组则表示进行session设置<br> * @param mixed $value session值<br> * @return mixed<br> */<br>function session($name,$value='') {<br>    $prefix   =  C('SESSION_PREFIX');<br>    if(is_array($name)) { // session初始化 在session_start 之前调用<br>        if(isset($name['prefix'])) C('SESSION_PREFIX',$name['prefix']);<br>        if(C('VAR_SESSION_ID') &amp;&amp; isset($_REQUEST[C('VAR_SESSION_ID')])){<br>            session_id($_REQUEST[C('VAR_SESSION_ID')]);<br>        }elseif(isset($name['id'])) {<br>            session_id($name['id']);<br>        }<br>        ini_set('session.auto_start', 0);<br>        if(isset($name['name']))            session_name($name['name']);<br>        if(isset($name['path']))            session_save_path($name['path']);<br>        if(isset($name['domain']))          ini_set('session.cookie_domain', $name['domain']);<br>        if(isset($name['expire']))          ini_set('session.gc_maxlifetime', $name['expire']);<br>        if(isset($name['use_trans_sid']))   ini_set('session.use_trans_sid', $name['use_trans_sid']?1:0);<br>        if(isset($name['use_cookies']))     ini_set('session.use_cookies', $name['use_cookies']?1:0);<br>        if(isset($name['cache_limiter']))   session_cache_limiter($name['cache_limiter']);<br>        if(isset($name['cache_expire']))    session_cache_expire($name['cache_expire']);<br>        if(isset($name['type']))            C('SESSION_TYPE',$name['type']);<br>        if(C('SESSION_TYPE')) { // 读取session驱动<br>            $class      = 'Session'. ucwords(strtolower(C('SESSION_TYPE')));<br>            // 检查驱动类<br>            if(require_cache(EXTEND_PATH.'Driver/Session/'.$class.'.class.php')) {<br>                $hander = new $class();<br>                $hander-&gt;execute();<br>            }else {<br>                // 类没有定义<br>                throw_exception(L('_CLASS_NOT_EXIST_').': ' . $class);<br>            }<br>        }<br>        // 启动session<br>        if(C('SESSION_AUTO_START'))  session_start();<br>    }elseif('' === $value){ <br>        if(0===strpos($name,'[')) { // session 操作<br>            if('[pause]'==$name){ // 暂停session<br>                session_write_close();<br>            }elseif('[start]'==$name){ // 启动session<br>                session_start();<br>            }elseif('[destroy]'==$name){ // 销毁session<br>                $_SESSION =  array();<br>                session_unset();<br>                session_destroy();<br>            }elseif('[regenerate]'==$name){ // 重新生成id<br>                session_regenerate_id();<br>            }<br>        }elseif(0===strpos($name,'?')){ // 检查session<br>            $name   =  substr($name,1);<div class="clear"></div>