使用file_get_contents从url获取JSON

Question

I have a server that provide some data in JSON. I tried to get these data with the usual:

$res = file_get_contents($url);
$result = json_decode($res);
var_dump($result);

But $result is yet a string. The problem is that the data that comes from file_get_content has some alphanumerical string before data and a zero after.

something like:

215ba
{"@attributes":{"ticker":"FCA"},"info...... // here all json data
0

I already checked json validity directly from the url and it's properly formatted, I can not understand where zero and 215ba come from.

Obviously I could strip the strings eliminating both but I was wondering if there was a more concrete solution instead of a workaround

PS: unfortunately I can not use cURL