CURLOPT_SSL_ENABLE_ALPN3
Application layer protocol negotiation
Usage
#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSL_ENABLE_ALPN, long npn);
Overview
Pass a long as parameter, 0 or 1 where 1 is for enable and 0 for disable. This option enables/disables ALPN in the SSL handshake (if the SSL backend libcurl is built to use supports it), which can be used to negotiate http2.
Default
1, enabled
Protocols
HTTP
Examples
int main(void)
{
CURL *curl = curl_easy_init();
if(curl) {
CURLcode res;
curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
curl_easy_setopt(curl, CURLOPT_SSL_ENABLE_ALPN, 0L);
res = curl_easy_perform(curl);
curl_easy_cleanup(curl);
}
}
Return value
Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.
Releases
79 releases since OS X 10.10; the text changed 13 times.