xref: /curl/docs/cmdline-opts/no-npn.md (revision 2494b8dd)
1---
2c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
3SPDX-License-Identifier: curl
4Long: no-npn
5Tags: Versions HTTP/2
6Protocols: HTTPS
7Added: 7.36.0
8Mutexed:
9Requires: TLS
10Help: Disable the NPN TLS extension
11Category: tls http
12Multi: boolean
13See-also:
14  - no-alpn
15  - http2
16Example:
17  - --no-npn $URL
18---
19
20# `--no-npn`
21
22curl never uses NPN, this option has no effect (added in 7.86.0).
23
24Disable the NPN TLS extension. NPN is enabled by default if libcurl was built
25with an SSL library that supports NPN. NPN is used by a libcurl that supports
26HTTP/2 to negotiate HTTP/2 support with the server during https sessions.
27