[vn4000]

You need initialize a new curl resource by:

$ch = curl_init();

Then set the url to fetch:

curl_setopt($ch, CURLOPT_URL, 'http://www.xxx.com');

If you want to return the value instead of printing the response to browser:

curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);

and:

$content = curl_exec($ch);

Please condider:
PHP: CURL - Manual
Good luck