登录后获取https的html

我想获取页面的html。经过一些谷歌搜索，我发现了以下代码，它不起作用。

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_USERPWD, "$username:$passwd");
curl_setopt($ch, CURLOPT_HTTPAUTH, CURLAUTH_BASIC);
$output = curl_exec($ch);
$info = curl_getinfo($ch);
curl_close($ch);
echo $output;

编辑：然后像这样：

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, '');
curl_setopt($ch, CURLOPT_POSTFIELDS,'username='.urlencode($username).'&passwd='.urlencode($passwd));
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_HEADER, 0);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, 1);
curl_setopt($ch, CURLOPT_COOKIEJAR, "/tmp/my_cookies.txt");
curl_setopt($ch, CURLOPT_COOKIEFILE, "/tmp/my_cookies.txt");
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    curl_setopt( $ch, CURLOPT_SSL_VERIFYPEER, false ); 
curl_setopt($ch, CURLOPT_USERAGENT, "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.3) Gecko/20070309 Firefox/2.0.0.3");
curl_setopt($ch, CURLOPT_REFERER, "");
$output = curl_exec($ch);
    echo $output

这只显示目标页面，它不会登录，也不会返回 html 代码。

编辑 2：现在尝试使用 $data = array（'用户名' => $username， 'passwd' => $passwd）; 和curl_setopt（$ch，CURLOPT_POSTFIELDS，$data）;这显示与上述相同+错误：请求实体太大