1CURLOPT_SSL_FALSESTART(3) curl_easy_setopt options CURLOPT_SSL_FALSESTART(3)
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6 CURLOPT_SSL_FALSESTART - enable TLS false start
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9 #include <curl/curl.h>
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11 CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSL_FALSESTART, long
12 enable);
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15 Pass a long as parameter set to 1L to enable or 0 to disable.
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17 This option determines whether libcurl should use false start during
18 the TLS handshake. False start is a mode where a TLS client will start
19 sending application data before verifying the server's Finished mes‐
20 sage, thus saving a round trip when performing a full handshake.
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23 0
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26 All TLS based protocols: HTTPS, FTPS, IMAPS, POP3S, SMTPS etc.
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29 CURL *curl = curl_easy_init();
30 if(curl) {
31 curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
32 curl_easy_setopt(curl, CURLOPT_SSL_FALSESTART, 1L);
33 curl_easy_perform(curl);
34 }
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37 Added in 7.42.0. This option is currently only supported by the NSS and
38 Secure Transport (on iOS 7.0 or later, or OS X 10.9 or later) TLS back‐
39 ends.
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42 Returns CURLE_OK if false start is supported by the SSL backend, other‐
43 wise returns CURLE_NOT_BUILT_IN.
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47libcurl 7.76.1 November 04, 2020 CURLOPT_SSL_FALSESTART(3)