php获取服务器信息常用方法（零碎知识记忆）

突然整理下零碎小知识.......加深下印象：

$info = array(
            ‘操作系统‘=>PHP_OS,
            ‘运行环境‘=>$_SERVER["SERVER_SOFTWARE"],
            ‘主机名‘=>$_SERVER[‘SERVER_NAME‘],
            ‘WEB服务端口‘=>$_SERVER[‘SERVER_PORT‘],
            ‘网站文档目录‘=>$_SERVER["DOCUMENT_ROOT"],
            ‘浏览器信息‘=>substr($_SERVER[‘HTTP_USER_AGENT‘], 0, 40),
            ‘通信协议‘=>$_SERVER[‘SERVER_PROTOCOL‘],
            ‘请求方法‘=>$_SERVER[‘REQUEST_METHOD‘],
            ‘上传附件限制‘=>ini_get(‘upload_max_filesize‘),
            ‘执行时间限制‘=>ini_get(‘max_execution_time‘).‘秒‘,
            ‘服务器时间‘=>date("Y年n月j日 H:i:s"),
            ‘北京时间‘=>gmdate("Y年n月j日 H:i:s",time()+8*3600),
            ‘服务器域名/IP‘=>$_SERVER[‘SERVER_NAME‘].‘ [ ‘.gethostbyname($_SERVER[‘SERVER_NAME‘]).‘ ]‘,
            ‘用户的IP地址‘=>$_SERVER[‘REMOTE_ADDR‘],
            ‘剩余空间‘=>round((disk_free_space(".")/(1024*1024)),2).‘M‘,
        );