HEAD / HTTP/1.1
Host: 127.0.0
User-Agent: curl/7.49.0-DEV
Accept:GET /x.txt HT91
connection: Upgrade,, HTTP2-Settings
upgrade: h2C
http2-settings: AA------------------P2-Set: nghttp2/1.16.1


--MARK--
PRI * H2ettingssfer:-En