open a socket on a shared host

I'm trying to open a socket on a host using the following code:

$timeout = 10;
$s = stream_socket_开发者_如何学编程client('mywebsite.com:80', $errcode, $errstring, $timeout);
$message = "GET /index.php HTTP/1.0\r\n\r\n";
fwrite($s, $message);
while(!feof($s)){
    echo fread($s, 1024);
}

Nothing fancy, just an example I found. The problem is that every time I run the code I get different files. I think this is because the host is a shared one.

Is there a way to overcome this problem, that is, pull reliably the proper file I'm trying to get?

Thank you.

---

in the HTTP request you have to specify which host you're accessing. as you noted correctly multiple DNS entries can point to the same IP address.

$message = "GET /index.php HTTP/1.1\r\nHost: hostname.com\r\n\r\n";

---

You need to send the Host header to specify the domain name - it is very common for one server to host multiple websites:

$message = "GET /index.php HTTP/1.1\r\nHost: www.example.com\r\n\r\n";

Note (as @Darhazer points out) that Host request header is only defined since HTTP/1.1, so you can't use it wtih HTTP/1.0. There is a possibility to use the absolute URL, as in

$message = "GET http://www.example.com/index.php HTTP/1.0\r\n\r\n";

but this is a violation of HTTP/1.0:

The absoluteURI form is only allowed when the request is being made to a proxy.

and the target server apparently isn't a proxy, so the resulting behavior is unreliable.