#include <curl/curl.h> CURLcode curl_easy_getinfo(CURL *handle, CURLINFO_TLS_SESSION, struct curl_tlssessioninfo **session);
This option is exactly the same as CURLINFO_TLS_SSL_PTR(3) except in the case of OpenSSL. If the session backend is CURLSSLBACKEND_OPENSSL the session internals pointer varies depending on the option:
CURLINFO_TLS_SESSION OpenSSL session internals is SSL_CTX *.
CURLINFO_TLS_SSL_PTR OpenSSL session internals is SSL *.
You can obtain an SSL_CTX pointer from an SSL pointer using OpenSSL function SSL_get_SSL_CTX. Therefore unless you need compatibility with older versions of libcurl use CURLINFO_TLS_SSL_PTR(3). Refer to that document for more information.
CURL *curl = curl_easy_init(); if(curl) { CURLcode res; struct curl_tlssessioninfo *tls; curl_easy_setopt(curl, CURLOPT_URL, "https://example.com"); res = curl_easy_perform(curl); curl_easy_getinfo(curl, CURLINFO_TLS_SESSION, &tls); curl_easy_cleanup(curl); }