File_get_content displays error every time the URL doesn't exist

[narutodude000]

        $d = file_get_contents($url);
        //display error if site can't be loaded
        if (!$d) { 
            return false;
        } 

Instead of returning false for me to handle, it returns this error:

[phpBB Debug] PHP Notice: in file public_html/functions.php on line 3810: file_get_contents() [function.file-get-contents]: php_network_getaddresses: getaddrinfo failed: Name or service not known
[phpBB Debug] PHP Notice: in file public_html/functions.php on line 3810: file_get_contents(http://a.com/) [function.file-get-contents]: failed to open stream: php_network_getaddresses: getaddrinfo failed: Name or service not known

How can I make it simply return false instead displaying this error?

[BIOSTALL]

What about this:

if (!$d = file_get_contents($url)) {
  return false;
} 

Or turn error reporting off haha