CURLOPT_SSL_FALSESTART(3)

1CURLOPT_SSL_FALSESTART(3)           libcurl          CURLOPT_SSL_FALSESTART(3)
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NAME

6       CURLOPT_SSL_FALSESTART - TLS false start
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SYNOPSIS

9       #include <curl/curl.h>
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11       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSL_FALSESTART, long enable);
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DESCRIPTION

14       Pass a long as parameter set to 1L to enable or 0 to disable.
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16       This  option  determines  whether libcurl should use false start during
17       the TLS handshake. False start is a mode where a TLS client will  start
18       sending  application  data  before verifying the server's Finished mes‐
19       sage, thus saving a round trip when performing a full handshake.
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DEFAULT

22       0
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PROTOCOLS

25       All TLS based protocols: HTTPS, FTPS, IMAPS, POP3S, SMTPS etc.
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EXAMPLE

28       CURL *curl = curl_easy_init();
29       if(curl) {
30         curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
31         curl_easy_setopt(curl, CURLOPT_SSL_FALSESTART, 1L);
32         curl_easy_perform(curl);
33       }
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AVAILABILITY

36       Added in 7.42.0. This option is currently only supported by the NSS and
37       Secure Transport (on iOS 7.0 or later, or OS X 10.9 or later) TLS back‐
38       ends.
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RETURN VALUE

41       Returns CURLE_OK if false start is supported by the SSL backend, other‐
42       wise returns CURLE_NOT_BUILT_IN.
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