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c: Copyright (C) Daniel Stenberg, daniel@haxx.se, et al. SPDX-License-Identifier: curl Long: no-alpn Tags: HTTP/2 Protocols: HTTPS Added: 7.36.0 Requires: TLS Help: Disable the ALPN TLS extension Category: tls http Multi: boolean See-also:

• no-npn
• http2 Example:
• --no-alpn $URL

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--no-alpn

Disable the ALPN TLS extension. ALPN is enabled by default if libcurl was built with an SSL library that supports ALPN. ALPN is used by a libcurl that supports HTTP/2 to negotiate HTTP/2 support with the server during https sessions.

Note that this is the negated option name documented. You can use --alpn to enable ALPN.