1 c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al. 2 SPDX-License-Identifier: curl 3 Long: http3-only 4 Tags: Versions 5 Protocols: HTTP 6 Added: 7.88.0 7 Mutexed: http1.1 http1.0 http2 http2-prior-knowledge http3 8 Requires: HTTP/3 9 Help: Use HTTP v3 only 10 See-also: http1.1 http2 http3 11 Category: http 12 Example: --http3-only $URL 13 Multi: mutex 14 Experimental: yes 15 --- 16 Instructs curl to use HTTP/3 to the host in the URL, with no fallback to 17 earlier HTTP versions. HTTP/3 can only be used for HTTPS and not for HTTP 18 URLs. For HTTP, this option triggers an error. 19 20 This option allows a user to avoid using the Alt-Svc method of upgrading to 21 HTTP/3 when you know that the target speaks HTTP/3 on the given host and port. 22 23 This option makes curl fail if a QUIC connection cannot be established, it 24 does not attempt any other HTTP versions on its own. Use --http3 for similar 25 functionality *with* a fallback. 26