CURLOPT_STREAM_WEIGHT - numerical stream weight
#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_STREAM_WEIGHT, long weight);
CURLOPT_STREAM_WEIGHT(3) curl_easy_setopt options CURLOPT_STREAM_WEIGHT(3)
NAME
CURLOPT_STREAM_WEIGHT - numerical stream weight
SYNOPSIS
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_STREAM_WEIGHT, long weight);
DESCRIPTION
Set the long weight to a number between 1 and 256.
When using HTTP/2, this option sets the individual weight for this par-
ticular stream used by the easy handle. Setting and using weights only
makes sense and is only usable when doing multiple streams over the
same connections, which thus implies that you use CURLMOPT_PIPELIN-
ING(3).
This option can be set during transfer and will then cause the updated
weight info get sent to the server the next time an HTTP/2 frame is
sent to the server.
See section 5.3 of RFC 7540 for protocol details:
https://httpwg.github.io/specs/rfc7540.html#StreamPriority
Streams with the same parent should be allocated resources proportion-
ally based on their weight. So if you have two streams going, stream A
with weight 16 and stream B with weight 32, stream B will get two
thirds (32/48) of the available bandwidth (assuming the server can send
off the data equally for both streams).
DEFAULT
If nothing is set, the HTTP/2 protocol itself will use its own default
which is 16.
PROTOCOLS
HTTP/2
EXAMPLE
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");
curl_easy_setopt(curl, CURLOPT_STREAM_WEIGHT, 10L);
/* the second has twice the weight */
curl_easy_setopt(curl2, CURLOPT_URL, "https://example.com/two");
curl_easy_setopt(curl2, CURLOPT_STREAM_WEIGHT, 20L);
/* 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.
ATTRIBUTES
See attributes(7) for descriptions of the following attributes:
+---------------+------------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+------------------+
|Availability | web/curl |
+---------------+------------------+
|Stability | Uncommitted |
+---------------+------------------+
SEE ALSO
CURLOPT_STREAM_DEPENDS(3), CURLOPT_STREAM_DEPENDS_E(3), CUR-
LOPT_PIPEWAIT(3), CURLMOPT_PIPELINING(3),
NOTES
Source code for open source software components in Oracle Solaris can
be found at https://www.oracle.com/downloads/opensource/solaris-source-
code-downloads.html.
This software was built from source available at
https://github.com/oracle/solaris-userland. The original community
source was downloaded from https://curl.se/down-
load/curl-7.83.1.tar.bz2.
Further information about this software can be found on the open source
community website at http://curl.haxx.se/.
libcurl 7.83.1 November 26, 2021 CURLOPT_STREAM_WEIGHT(3)