在PHP中检索Twitter的X-RateLimit-Limit - Retrieve Twitter's X-RateLimit-Limit in PHP

对于我发出的每个Twitter请求，返回的HTTP标头都应包含X-RateLimit-Limit。

但是，我似乎无法使用PHP检索这些内容。有人能告诉我我犯了什么愚蠢的错误吗？

我已经以正常方式设置了我的卷发，并且能够成功获取和开机自检请求。

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);
curl_setopt($ch, CURLOPT_HTTPHEADER, array('Expect:'));
curl_setopt($ch, CURLOPT_TIMEOUT, 10);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 0);
curl_setopt($ch, CURLOPT_HEADER, FALSE);
curl_setopt($ch, CURLINFO_HEADER_OUT, TRUE);
curl_setopt($ch, CURLOPT_VERBOSE, TRUE);
$response = curl_exec($ch);
$response_info=curl_getinfo($ch);
$erno = curl_errno($ch);
$er = curl_error($ch);
curl_close($ch);

我能够获得一些响应信息，例如http_code

$response_info['http_code']

但是这条线只返回空

值

//Doesn't bloody work. No idea why!
$rate_limit = $response_info['X-RateLimit-Limit'];

我正在运行PHP版本5.3.10。

编辑

这是 print_r（$response_info）的结果;

Array
(
[url] => https://api.twitter.com/1/statuses/home_timeline.json...
[content_type] => application/json;charset=utf-8
[http_code] => 200
[header_size] => 695
[request_size] => 410
[filetime] => -1
[ssl_verify_result] => 0
[redirect_count] => 0
[total_time] => 1.239977
[namelookup_time] => 0.007361
[connect_time] => 0.155783
[pretransfer_time] => 0.465397
[size_upload] => 0
[size_download] => 99425
[speed_download] => 80182
[speed_upload] => 0
[download_content_length] => 99425
[upload_content_length] => 0
[starttransfer_time] => 0.794829
[redirect_time] => 0
[certinfo] => Array()
[redirect_url] => 
[request_header] => GET /1/statuses/home_timeline.json... HTTP/1.1
Host: api.twitter.com
Accept: */*
)

>curl_getinfo不返回响应标头，只返回有关请求的其他元信息。要检索标头，请将CURLOPT_HEADER设置为 true 。这将包括输出中的标头。要将它们与响应正文分开，请执行以下操作：

list($headers, $body) = explode("'n'n", $response, 2);

要解析标头，请再次爆炸：

$headers = explode("'n", $headers);
foreach ($headers as $header) {
    list($key, $value) = explode(':', $header, 2);
    $headers[trim($key)] = trim($value);
}
echo $headers['X-RateLimit-Limit'];