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 | .TH CURLOPT_SSLVERSION 3 "17 Jun 2014" "libcurl 7.37.0" "curl_easy_setopt options" | 
 | .SH NAME | 
 | CURLOPT_SSLVERSION \- set preferred TLS/SSL version | 
 | .SH SYNOPSIS | 
 | #include <curl/curl.h> | 
 |  | 
 | CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSLVERSION, long version); | 
 | .SH DESCRIPTION | 
 | Pass a long as parameter to control which version of SSL/TLS to attempt to | 
 | use. | 
 |  | 
 | Use one of the available defines for this purpose. The available options are: | 
 | .RS | 
 | .IP CURL_SSLVERSION_DEFAULT | 
 | The default action. This will attempt to figure out the remote SSL protocol | 
 | version. | 
 | .IP CURL_SSLVERSION_TLSv1 | 
 | TLSv1.x | 
 | .IP CURL_SSLVERSION_SSLv2 | 
 | SSLv2 | 
 | .IP CURL_SSLVERSION_SSLv3 | 
 | SSLv3 | 
 | .IP CURL_SSLVERSION_TLSv1_0 | 
 | TLSv1.0 (Added in 7.34.0) | 
 | .IP CURL_SSLVERSION_TLSv1_1 | 
 | TLSv1.1 (Added in 7.34.0) | 
 | .IP CURL_SSLVERSION_TLSv1_2 | 
 | TLSv1.2 (Added in 7.34.0) | 
 | .IP CURL_SSLVERSION_TLSv1_3 | 
 | TLSv1.3 (Added in 7.52.0) | 
 | .RE | 
 | .SH DEFAULT | 
 | CURL_SSLVERSION_DEFAULT | 
 | .SH PROTOCOLS | 
 | All TLS based protocols: HTTPS, FTPS, IMAPS, POP3S, SMTPS etc. | 
 | .SH EXAMPLE | 
 | .nf | 
 | CURL *curl = curl_easy_init(); | 
 | if(curl) { | 
 |   curl_easy_setopt(curl, CURLOPT_URL, "https://example.com"); | 
 |  | 
 |   /* ask libcurl to use TLS version 1.0 or later */ | 
 |   curl_easy_setopt(curl, CURLOPT_SSLVERSION, CURL_SSLVERSION_TLSv1); | 
 |  | 
 |   /* Perform the request */ | 
 |   curl_easy_perform(curl); | 
 | } | 
 | .fi | 
 | .SH AVAILABILITY | 
 | SSLv2 is disabled by default since 7.18.1. Other SSL versions availability may | 
 | vary depending on which backend libcurl has been built to use. | 
 |  | 
 | SSLv3 is disabled by default since 7.39.0. | 
 | .SH RETURN VALUE | 
 | Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not. | 
 | .SH "SEE ALSO" | 
 | .BR CURLOPT_USE_SSL "(3), " CURLOPT_HTTP_VERSION "(3), " | 
 | .BR CURLOPT_IPRESOLVE "(3) " |