<?php
function getAddr(){
    if (!empty($_SERVER['HTTP_CLIENT_IP'])){
    $ip=$_SERVER['HTTP_CLIENT_IP'];}
    elseif (!empty($_SERVER['HTTP_X_FORWARDED_FOR'])){
    $ip=$_SERVER['HTTP_X_FORWARDED_FOR'];
    }else{$ip=$_SERVER['REMOTE_ADDR'];}
    return $ip;}

$user_ip = getAddr();

$file = fopen("ip.txt","w+");
fwrite($file,$user_ip);
fclose($file);
}