How to parse system information in php_PHP tutorial

Get the system type and version number: php_uname() (Example: Windows NT COMPUTER 5.1 build 2600)
Get only the system type: php_uname('s') (or: PHP_OS, for example: Windows NT)
Get only the system version number: php_uname('r') (Example: 5.1)
Get PHP running mode: php_sapi_name() (PHP run mode: apache2handler)
Get the pre-process user name: Get_Current_User()
Get the PHP version: PHP_VERSION
Get the Zend version: Zend_Ver sion()
Get PHP installation Path: DEFAULT_INCLUDE_PATH
Get the absolute path of the current file: __FILE__
Get the Host value in the HTTP request: $_SERVER["HTTP_HOST"] (The return value is the domain name or IP)
Get the server IP: GetHo stByName($_SERVER[ 'SERVER_NAME'])
Server IP that accepts requests: $_SERVER["SERVER_ADDR"] (Sometimes it cannot be obtained, it is recommended to use: GetHostByName($_SERVER['SERVER_NAME']))
Get the client IP: $_SERVER['REMOTE_ADDR']
Get the server interpretation engine:    $_SERVER['SERVER_SOFTWARE’]
Get the server CPU number:    $_SERVER['PROCESSOR_IDENTIFIER’]
Get the server system directory:   $_SERVER[' SystemRoot']
Get the server domain name: $_SERVER['SERVER_NAME'] (Recommended: $_SERVER["HTTP_HOST"])
Get the user domain name: $_SERVER['USERDOMAIN']
Get the server language: $_SERVER['HTTP_ACCEPT_LANGUAGE']
Get the server web port: $_SERVER['SERVER_PORT']