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23 .TH CURLOPT_SSL_ENABLE_ALPN 3 "May 31, 2017" "libcurl 7.59.0" "curl_easy_setopt options"
26 CURLOPT_SSL_ENABLE_ALPN \- enable ALPN
28 #include <curl/curl.h>
30 CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSL_ENABLE_ALPN, long npn);
32 Pass a long as parameter, 0 or 1 where 1 is for enable and 0 for disable. This
33 option enables/disables ALPN in the SSL handshake (if the SSL backend libcurl
34 is built to use supports it), which can be used to negotiate http2.
41 CURL *curl = curl_easy_init();
43 curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
44 curl_easy_setopt(curl, CURLOPT_SSL_ENABLE_ALPN, 0L);
45 ret = curl_easy_perform(curl);
46 curl_easy_cleanup(curl);
52 Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.
54 .BR CURLOPT_SSL_ENABLE_NPN "(3), " CURLOPT_SSL_OPTIONS "(3), "