curl exec僅返回null

Question

PHP代碼

function file_get_contents_curl($url) {
    try {
            $ch = curl_init();

            if (FALSE === $ch)
                throw new Exception('failed to initialize');

            curl_setopt($ch, CURLOPT_URL, $url);
            curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
            curl_setopt($ch, CURLOPT_HEADER, 0);
            curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); //Set curl to return the data instead of printing it to the browser.
            curl_setopt($ch, CURLOPT_URL, $url);
            curl_setopt($ch, CURLOPT_TIMEOUT, 10); 

            $content = curl_exec($ch);

            if (FALSE === $content)
                throw new Exception(curl_error($ch), curl_errno($ch));


            return $content;
        } catch(Exception $e) {

            trigger_error(sprintf(
                'Curl failed with error #%d: %s',
                $e->getCode(), $e->getMessage()),
                E_USER_ERROR);

        }
}

我稱這個函數為var_dump(file_get_contents_curl("http://www.google.com"));die; 但這返回的只是null； 我在具有相同配置的其他服務器上運行了此代碼，並正常工作，

allow_url_fopen已開啟

還可以file_get_contents('http://www.google.com/')向我返回false file_get_contents('http://www.google.com/') ？？？？

我非常非常困惑。請幫助我:(