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функция не описана

Requests_Transport_cURL::stream_headers() public WP 1.0

Collect the headers as they are received

Это метод класса: Requests_Transport_cURL{}

Хуков нет.

Возвращает

Число. Length of provided header

Использование

$Requests_Transport_cURL = new Requests_Transport_cURL();
$Requests_Transport_cURL->stream_headers( $handle, $headers );
$handle(resource) (обязательный)
cURL resource
$headers(строка) (обязательный)
Header string

Код Requests_Transport_cURL::stream_headers() WP 5.5.1

wp-includes/Requests/Transport/cURL.php
<?php
public function stream_headers($handle, $headers) {
	// Why do we do this? cURL will send both the final response and any
	// interim responses, such as a 100 Continue. We don't need that.
	// (We may want to keep this somewhere just in case)
	if ($this->done_headers) {
		$this->headers = '';
		$this->done_headers = false;
	}
	$this->headers .= $headers;

	if ($headers === "\r\n") {
		$this->done_headers = true;
	}
	return strlen($headers);
}