For all the questions related to server, or current files, or system using, you get the answer from a single php global variable:
it is $_SERVER.
just print_r($_SERVER) the variable you get all the details.
How to get get the client IP address in PHP ?
print_r($_SERVER[‘HTTP_CLIENT_IP’]);
print_r($_SERVER[‘REMOTE_ADDR’]);
print_r($_SERVER[‘HTTP_X_FORWARDED_FOR’]);
How to get get the browser using in PHP ?
print_r($_SERVER[‘HTTP_USER_AGENT’]);
How to get get the filename using in PHP ?
print_r($_SERVER[‘PHP_SELF’]);
How to get host name or server name in php ?
print_r($_SERVER[‘SERVER_NAME’]);