1CURLOPT_STREAM_WEIGHT(3) curl_easy_setopt options CURLOPT_STREAM_WEIGHT(3)
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6 CURLOPT_STREAM_WEIGHT - numerical stream weight
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9 #include <curl/curl.h>
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11 CURLcode curl_easy_setopt(CURL *handle, CURLOPT_STREAM_WEIGHT, long weight);
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14 Set the long weight to a number between 1 and 256.
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16 When using HTTP/2, this option sets the individual weight for this par‐
17 ticular stream used by the easy handle. Setting and using weights only
18 makes sense and is only usable when doing multiple streams over the
19 same connections, which thus implies that you use CURLMOPT_PIPELIN‐
20 ING(3).
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22 This option can be set during transfer and will then cause the updated
23 weight info get sent to the server the next time an HTTP/2 frame is
24 sent to the server.
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26 See section 5.3 of RFC 7540 for protocol details:
27 https://httpwg.github.io/specs/rfc7540.html#StreamPriority
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29 Streams with the same parent should be allocated resources proportion‐
30 ally based on their weight. So if you have two streams going, stream A
31 with weight 16 and stream B with weight 32, stream B will get two
32 thirds (32/48) of the available bandwidth (assuming the server can send
33 off the data equally for both streams).
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36 If nothing is set, the HTTP/2 protocol itself will use its own default
37 which is 16.
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40 HTTP/2
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43 CURL *curl = curl_easy_init();
44 CURL *curl2 = curl_easy_init(); /* a second handle */
45 if(curl) {
46 curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/one");
47 curl_easy_setopt(curl, CURLOPT_STREAM_WEIGHT, 10L);
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49 /* the second has twice the weight */
50 curl_easy_setopt(curl2, CURLOPT_URL, "https://example.com/two");
51 curl_easy_setopt(curl2, CURLOPT_STREAM_WEIGHT, 20L);
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53 /* then add both to a multi handle and transfer them! */
54 }
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57 Added in 7.46.0
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60 Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION
61 if not.
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64 CURLOPT_STREAM_DEPENDS(3), CURLOPT_STREAM_DEPENDS_E(3), CUR‐
65 LOPT_PIPEWAIT(3), CURLMOPT_PIPELINING(3),
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69libcurl 7.85.0 May 17, 2022 CURLOPT_STREAM_WEIGHT(3)