以编程方式将文件下载到内存php

Hi I would like to know how to download a file to a variable (or memory) with php. I have tried using file_get_contents and a few RSS feed php libraries with no output (even with var_dump). This is the url that I am trying to access:

http://www.facebook.com/feeds/friends_status.php?id=MY_USER_ID&key=SECRET_KEY&format=rss20

MY_USER_ID is my facebook id, SECRET_KEY is the secret key. I am using the RSS feed method because I have tried for approximately 5 hours to make a facebook canvas application that fetches my friend's names and statuses with no success.

EDIT: You can access the feed without 404 errors by replacing the "http" with "feed"

A lot of API's require a user agent string. So you could try setting that. You can use cURL to get the file, and change the headers. Try this function:

    function getUrl($url) {
        $ch = curl_init($url);
        curl_setopt($ch, CURLOPT_USERAGENT, "Mozilla/5.0");
        curl_setopt($ch, CURLOPT_HEADER, 0);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
        $output = curl_exec($ch);      
        curl_close($ch);
        return $output;
    }

Usage:

$file = getUrl('http://www.facebook.com/feeds/friends_status.php?id=MY_USER_ID&key=SECRET_KEY&format=rss20')