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.TH CURLOPT_PROXY_TLS13_CIPHERS 3 "25 May 2018" libcurl libcurl
.SH NAME
CURLOPT_PROXY_TLS13_CIPHERS \- ciphers suites for proxy TLS 1.3
.SH SYNOPSIS
.nf
#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_PROXY_TLS13_CIPHERS,
                          char *list);
.fi
.SH DESCRIPTION
Pass a char *, pointing to a null-terminated string holding the list of cipher
suites to use for the TLS 1.3 connection to a proxy. The list must be
syntactically correct, it consists of one or more cipher suite strings
separated by colons.

you will find more details about cipher lists on this URL:

 https://curl.se/docs/ssl-ciphers.html

This option is currently used only when curl is built to use OpenSSL 1.1.1 or
later. If you are using a different SSL backend you can try setting TLS 1.3
cipher suites by using the \fICURLOPT_PROXY_SSL_CIPHER_LIST(3)\fP option.

The application does not have to keep the string around after setting this
option.
.SH DEFAULT
NULL, use internal 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/");
  curl_easy_setopt(curl, CURLOPT_PROXY_TLS13_CIPHERS,
                   "TLS_CHACHA20_POLY1305_SHA256");
  ret = curl_easy_perform(curl);
  curl_easy_cleanup(curl);
}
.fi
.SH AVAILABILITY
Added in 7.61.0.
Available when built with OpenSSL >= 1.1.1.
.SH RETURN VALUE
Returns CURLE_OK if supported, CURLE_NOT_BUILT_IN otherwise.
.SH "SEE ALSO"
.BR CURLOPT_PROXY_SSL_CIPHER_LIST "(3), " CURLOPT_PROXY_SSLVERSION "(3), "
.BR CURLOPT_SSL_CIPHER_LIST "(3), " CURLOPT_TLS13_CIPHERS "(3), "
.BR CURLOPT_SSLVERSION "(3), "