curl/docs/libcurl/opts/CURLOPT_STREAM_DEPENDS.md
Daniel Stenberg e3fe020089
docs/libcurl: generate PROTOCOLS from meta-data
Remove the PROTOCOLS section from the source files completely and
instead generate them based on the header data in the curldown files.

It also generates TLS backend information for options marked for TLS as
protocol.

Closes #13175
2024-03-23 18:13:03 +01:00

76 lines
1.8 KiB
Markdown

---
c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
SPDX-License-Identifier: curl
Title: CURLOPT_STREAM_DEPENDS
Section: 3
Source: libcurl
See-also:
- CURLMOPT_PIPELINING (3)
- CURLOPT_HTTP_VERSION (3)
- CURLOPT_STREAM_DEPENDS_E (3)
- CURLOPT_STREAM_WEIGHT (3)
Protocol:
- HTTP
---
# NAME
CURLOPT_STREAM_DEPENDS - stream this transfer depends on
# SYNOPSIS
~~~c
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_STREAM_DEPENDS,
CURL *dephandle);
~~~
# DESCRIPTION
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 makes this function return
an error. It must be another easy handle, and it also needs to be a handle of
a transfer that is about to be sent over the same HTTP/2 connection for this
option to have an actual effect.
# DEFAULT
NULL
# EXAMPLE
~~~c
int main(void)
{
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! */
}
}
~~~
# AVAILABILITY
Added in 7.46.0
# RETURN VALUE
Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.