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.TH CURLOPT_PROXY_SSLVERSION 3 "16 Nov 2016" "libcurl 7.52.0" "curl_easy_setopt options"
.SH NAME
CURLOPT_PROXY_SSLVERSION \- set preferred proxy TLS/SSL version
.SH SYNOPSIS
#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_PROXY_SSLVERSION, long version);
.SH DESCRIPTION
Pass a long as parameter to control which version of SSL/TLS to attempt to use
when connecting to an HTTPS proxy.

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_TLSv1_0
TLSv1.0
.IP CURL_SSLVERSION_TLSv1_1
TLSv1.1
.IP CURL_SSLVERSION_TLSv1_2
TLSv1.2
.IP CURL_SSLVERSION_TLSv1_3
TLSv1.3
.IP CURL_SSLVERSION_MAX_DEFAULT
The flag defines maximum supported TLS version as TLSv1.2 or default
value from SSL library. Only library NSS currently allows to get
maximum supported TLS version.
(Added in 7.54.0)
.IP CURL_SSLVERSION_MAX_TLSv1_0
The flag defines maximum supported TLS version as TLSv1.0.
(Added in 7.54.0)
.IP CURL_SSLVERSION_MAX_TLSv1_1
The flag defines maximum supported TLS version as TLSv1.1.
(Added in 7.54.0)
.IP CURL_SSLVERSION_MAX_TLSv1_2
The flag defines maximum supported TLS version as TLSv1.2.
(Added in 7.54.0)
.IP CURL_SSLVERSION_MAX_TLSv1_3
The flag defines maximum supported TLS version as TLSv1.3.
(Added in 7.54.0)
.RE
.SH DEFAULT
CURL_SSLVERSION_DEFAULT
.SH PROTOCOLS
All
.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_PROXY_SSLVERSION, CURL_SSLVERSION_TLSv1_1 |
                   CURL_SSLVERSION_MAX_DEFAULT);

  /* Perform the request */
  curl_easy_perform(curl);
}
.fi
.SH AVAILABILITY
Added in 7.52.0
.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) " CURLOPT_SSLVERSION "(3), "