NAME

       CURLOPT_HTTP_VERSION - specify HTTP protocol version to use

SYNOPSIS

       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_HTTP_VERSION, long version);

DESCRIPTION

       Pass  version a long, set to one of the values described below. They ask libcurl to use the specific HTTP
       versions. This is not sensible to do unless you have a good reason. You have to set this  option  if  you
       want to use libcurl's HTTP/2 support.

       Note  that  the  HTTP  version  is  just  a  request. libcurl will still prioritize to re-use an existing
       connection so it might then re-use a connection using a HTTP version you haven't asked for.

       CURL_HTTP_VERSION_NONE
              We don't care about what version the library uses. libcurl will use whatever it thinks fit.

       CURL_HTTP_VERSION_1_0
              Enforce HTTP 1.0 requests.

       CURL_HTTP_VERSION_1_1
              Enforce HTTP 1.1 requests.

       CURL_HTTP_VERSION_2_0
              Attempt HTTP 2 requests. libcurl will fall back to HTTP 1.1 if HTTP 2 can't be negotiated with the
              server. (Added in 7.33.0)

              The alias CURL_HTTP_VERSION_2 was added in 7.43.0 to better reflect the actual protocol name.

       CURL_HTTP_VERSION_2TLS
              Attempt  HTTP  2  over  TLS  (HTTPS)  only.  libcurl will fall back to HTTP 1.1 if HTTP 2 can't be
              negotiated with the HTTPS server. For clear text HTTP servers, libcurl will  use  1.1.  (Added  in
              7.47.0)

DEFAULT

       CURL_HTTP_VERSION_NONE

PROTOCOLS

       HTTP

EXAMPLE

       TODO

AVAILABILITY

       Along with HTTP

RETURN VALUE

       Returns CURLE_OK if HTTP is supported, and CURLE_UNKNOWN_OPTION if not.

SEE ALSO

       CURLOPT_SSLVERSION(3), CURLOPT_HTTP200ALIASES(3),