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                     23: .TH CURLOPT_STREAM_WEIGHT 3 "March 23, 2020" "libcurl 7.70.0" "curl_easy_setopt options"
                     24: 
                     25: .SH NAME
                     26: CURLOPT_STREAM_WEIGHT \- set numerical stream weight
                     27: .SH SYNOPSIS
                     28: #include <curl/curl.h>
                     29: 
                     30: CURLcode curl_easy_setopt(CURL *handle, CURLOPT_STREAM_WEIGHT, long weight);
                     31: .SH DESCRIPTION
                     32: Set the long \fIweight\fP to a number between 1 and 256.
                     33: 
                     34: When using HTTP/2, this option sets the individual weight for this particular
                     35: stream used by the easy \fIhandle\fP. Setting and using weights only makes
                     36: sense and is only usable when doing multiple streams over the same
                     37: connections, which thus implies that you use \fICURLMOPT_PIPELINING(3)\fP.
                     38: 
                     39: This option can be set during transfer and will then cause the updated weight
                     40: info get sent to the server the next time an HTTP/2 frame is sent to the
                     41: server.
                     42: 
                     43: See section 5.3 of RFC 7540 for protocol details:
                     44: https://httpwg.github.io/specs/rfc7540.html#StreamPriority
                     45: 
                     46: Streams with the same parent should be allocated resources proportionally
                     47: based on their weight. So if you have two streams going, stream A with weight
                     48: 16 and stream B with weight 32, stream B will get two thirds (32/48) of the
                     49: available bandwidth (assuming the server can send off the data equally for
                     50: both streams).
                     51: .SH DEFAULT
                     52: If nothing is set, the HTTP/2 protocol itself will use its own default which
                     53: is 16.
                     54: .SH PROTOCOLS
                     55: HTTP/2
                     56: .SH EXAMPLE
                     57: .nf
                     58: CURL *curl = curl_easy_init();
                     59: CURL *curl2 = curl_easy_init(); /* a second handle */
                     60: if(curl) {
                     61:   curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/one");
                     62:   curl_easy_setopt(curl, CURLOPT_STREAM_WEIGHT, 10L);
                     63: 
                     64:   /* the second has twice the weight */
                     65:   curl_easy_setopt(curl2, CURLOPT_URL, "https://example.com/two");
                     66:   curl_easy_setopt(curl2, CURLOPT_STREAM_WEIGHT, 20L);
                     67: 
                     68:   /* then add both to a multi handle and transfer them! */
                     69: }
                     70: .fi
                     71: .SH AVAILABILITY
                     72: Added in 7.46.0
                     73: .SH RETURN VALUE
                     74: Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.
                     75: .SH "SEE ALSO"
                     76: .BR CURLOPT_STREAM_DEPENDS "(3), " CURLOPT_STREAM_DEPENDS_E "(3), "
                     77: .BR CURLOPT_PIPEWAIT "(3), " CURLMOPT_PIPELINING "(3), "