diff --git a/curl-sys/lib.rs b/curl-sys/lib.rs index d0e9aa653..46a51a39c 100644 --- a/curl-sys/lib.rs +++ b/curl-sys/lib.rs @@ -660,7 +660,7 @@ pub const CURL_HTTP_VERSION_2TLS: c_int = 4; /// Please use HTTP 2 without HTTP/1.1 Upgrade /// (Added in CURL 7.49.0) pub const CURL_HTTP_VERSION_2_PRIOR_KNOWLEDGE: c_int = 5; -/// Makes use of explicit HTTP/3 without fallback. +/// Use HTTP/3, fallback to HTTP/2 or HTTP/1 if needed. /// (Added in CURL 7.66.0) pub const CURL_HTTP_VERSION_3: c_int = 30; diff --git a/src/easy/handler.rs b/src/easy/handler.rs index 95e365ffb..e944b877c 100644 --- a/src/easy/handler.rs +++ b/src/easy/handler.rs @@ -453,12 +453,11 @@ pub enum HttpVersion { V2PriorKnowledge = curl_sys::CURL_HTTP_VERSION_2_PRIOR_KNOWLEDGE as isize, /// Setting this value will make libcurl attempt to use HTTP/3 directly to - /// server given in the URL. Note that this cannot gracefully downgrade to - /// earlier HTTP version if the server doesn't support HTTP/3. + /// server given in the URL but fallback to earlier HTTP versions if the HTTP/3 + /// connection establishment fails. /// - /// For more reliably upgrading to HTTP/3, set the preferred version to - /// something lower and let the server announce its HTTP/3 support via - /// Alt-Svc:. + /// Note: the meaning of this settings depends on the linked libcurl. + /// For CURL < 7.88.0, there is no fallback if HTTP/3 connection fails. /// /// (Added in CURL 7.66.0) V3 = curl_sys::CURL_HTTP_VERSION_3 as isize,