Provided by: libcurl4-doc_7.58.0-2ubuntu3.24_all
NAME
CURLOPT_SSL_FALSESTART - enable 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 message, 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 backends.
RETURN VALUE
Returns CURLE_OK if false start is supported by the SSL backend, otherwise returns CURLE_NOT_BUILT_IN.