**************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at https://curl.haxx.se/docs/copyright.html.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the COPYING file.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
**************************************************************************

CURLOPT_STREAM_DEPENDS - set stream this transfer depends on #include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_STREAM_DEPENDS, CURL *dephandle); Pass a CURL * pointer in dephandle to identify the stream within the same connection that this stream is depending upon. This option clears the exclusive bit and is mutually exclusive to the CURLOPT_STREAM_DEPENDS_E(3) option. The spec says "Including a dependency expresses a preference to allocate resources to the identified stream rather than to the dependent stream." This option can be set during transfer. dephandle must not be the same as handle, that will cause this function to return an error. It must be another easy handle, and it also needs to be a handle of a transfer that will be sent over the same HTTP/2 connection for this option to have an actual effect. NULL HTTP/2

CURL *curl = curl_easy_init();
CURL *curl2 = curl_easy_init(); /* a second handle */
if(curl) {
 curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/one");

 /* the second depends on the first */
 curl_easy_setopt(curl2, CURLOPT_URL, "https://example.com/two");
 curl_easy_setopt(curl2, CURLOPT_STREAM_DEPENDS, curl);

 /* then add both to a multi handle and transfer them! */
}

Added in 7.46.0 Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not. CURLOPT_STREAM_WEIGHT "(3), " CURLOPT_STREAM_DEPENDS_E "(3), "