CURLOPT_SSL_ENABLE_NPN(3)

1CURLOPT_SSL_ENABLE_NPN(3)  curl_easy_setopt options  CURLOPT_SSL_ENABLE_NPN(3)
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NAME

6       CURLOPT_SSL_ENABLE_NPN - enable NPN
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SYNOPSIS

9       #include <curl/curl.h>
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11       CURLcode  curl_easy_setopt(CURL  *handle,  CURLOPT_SSL_ENABLE_NPN, long
12       npn);
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DESCRIPTION

15       Pass a long as parameter, 0 or 1 where 1 is for enable and 0  for  dis‐
16       able. This option enables/disables NPN in the SSL handshake (if the SSL
17       backend libcurl is built to use supports it),  which  can  be  used  to
18       negotiate http2.
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DEFAULT

21       1, enabled
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PROTOCOLS

24       HTTP
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EXAMPLE

27       CURL *curl = curl_easy_init();
28       if(curl) {
29         curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
30         curl_easy_setopt(curl, CURLOPT_SSL_ENABLE_NPN, 1L);
31         ret = curl_easy_perform(curl);
32         curl_easy_cleanup(curl);
33       }
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AVAILABILITY

36       Added in 7.36.0
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RETURN VALUE

39       Returns  CURLE_OK  if the option is supported, and CURLE_UNKNOWN_OPTION
40       if not.
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