1--- 2c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al. 3SPDX-License-Identifier: curl 4Long: http2-prior-knowledge 5Tags: Versions 6Protocols: HTTP 7Added: 7.49.0 8Mutexed: http1.1 http1.0 http2 http3 9Requires: HTTP/2 10Help: Use HTTP 2 without HTTP/1.1 Upgrade 11Category: http 12Multi: boolean 13See-also: 14 - http2 15 - http3 16Example: 17 - --http2-prior-knowledge $URL 18--- 19 20# `--http2-prior-knowledge` 21 22Issue a non-TLS HTTP requests using HTTP/2 directly without HTTP/1.1 Upgrade. 23It requires prior knowledge that the server supports HTTP/2 straight away. 24HTTPS requests still do HTTP/2 the standard way with negotiated protocol 25version in the TLS handshake. 26