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Updated: Wednesday, July 27, 2022
 
 

CURLOPT_SSL_FALSESTART (3)

Name

CURLOPT_SSL_FALSESTART - TLS false start

Synopsis

#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSL_FALSESTART, long enable);

Description

CURLOPT_SSL_FALSESTART(3)  curl_easy_setopt options  CURLOPT_SSL_FALSESTART(3)



NAME
       CURLOPT_SSL_FALSESTART - TLS false start

SYNOPSIS
       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSL_FALSESTART, long enable);

DESCRIPTION
       Pass a long as parameter set to 1L to enable or 0 to disable.

       This  option  determines  whether libcurl should use false start during
       the TLS handshake. False start is a mode where a TLS client will  start
       sending  application  data  before verifying the server's Finished mes-
       sage, thus saving a round trip when performing a full handshake.

DEFAULT
       0

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

EXAMPLE
       CURL *curl = curl_easy_init();
       if(curl) {
         curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
         curl_easy_setopt(curl, CURLOPT_SSL_FALSESTART, 1L);
         curl_easy_perform(curl);
       }

AVAILABILITY
       Added in 7.42.0. This option is currently only supported by the NSS and
       Secure Transport (on iOS 7.0 or later, or OS X 10.9 or later) TLS back-
       ends.

RETURN VALUE
       Returns CURLE_OK if false start is supported by the SSL backend, other-
       wise returns CURLE_NOT_BUILT_IN.


ATTRIBUTES
       See attributes(7) for descriptions of the following attributes:


       +---------------+------------------+
       |ATTRIBUTE TYPE | ATTRIBUTE VALUE  |
       +---------------+------------------+
       |Availability   | web/curl         |
       +---------------+------------------+
       |Stability      | Uncommitted      |
       +---------------+------------------+

SEE ALSO
       CURLOPT_TCP_FASTOPEN(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_SSL_FALSESTART(3)