php gets local ip (remote IP address)

Example, php gets user IP address.

// 111111111111
echo $_SERVER['REMOTE_ADDR'];

// 222222222222
function get_local_ip() {
 $preg = "/ A((([0-9] ?[0-9])|(1[0-9]{2})|(2[0-4][0-9])|(25[0-5])).){3}(( [0-9]?[0-9])|(1[0-9]{2})|(2[0-4][0-9])|(25[0-5]))Z/ ";
//Get the real IP address of the machine whose operating system is win2000/xp or win7
 exec("ipconfig", $out, $stats);
 if (!emptyempty($out)) {
 foreach ($out AS $row) {
 if (strstr($row, "IP") && strstr($row, ":") && !strstr($row, "IPv6")) {
 $tmpIp = explode(":", $row);
 if (preg_match($preg, trim($tmpIp[1]))) {
 return trim($tmpIp[1]);
 }
 }
 } bbs.it-home.org
 }
 //Get the real IP address of the machine whose operating system is Linux type
 exec("ifconfig", $out, $stats);
 if (!emptyempty($out)) {
 if (isset($out[1]) && strstr($out[1], 'addr:')) {
 $tmpArray = explode(":", $out[1]);
 $tmpIp = explode(" ", $tmpArray[1]);
 if (preg_match($preg, trim($tmpIp[0]))) {
 return trim($tmpIp[0]);
 }
 }
 }
 return '127.0.0.1';
}