Set ssl engine identifier
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSLENGINE, char *id);
Pass a pointer to a zero terminated string as parameter. It will be used as the identifier for the crypto engine you want to use for your private key.
If the crypto device cannot be loaded, CURLE_SSL_ENGINE_NOTFOUND is returned.
All TLS based protocols: HTTPS, FTPS, IMAPS, POP3, SMTPS etc.
If built TLS enabled.
Returns CURLE_OK if TLS is supported, CURLE_UNKNOWN_OPTION if not, or CURLE_OUT_OF_MEMORY if there was insufficient heap space.