curl/docs/cmdline-opts/no-keepalive.md

c	SPDX-License-Identifier	Long	Help	Category	Added	Multi	See-also	Example
Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.	curl	no-keepalive	Disable TCP keepalive on the connection	connection	7.18.0	boolean	keepalive-time keepalive-cnt	--no-keepalive $URL

--no-keepalive

Disables the use of keepalive messages on the TCP connection. curl otherwise enables them by default.

Note that this is the negated option name documented. You can thus use --keepalive to enforce keepalive.