curl/docs/cmdline-opts/ipv4.md

c	SPDX-License-Identifier	Short	Long	Tags	Protocols	Added	Mutexed	Requires	Help	Category	Multi	See-also	Example
Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.	curl	4	ipv4	Versions		7.10.8	ipv6		Resolve names to IPv4 addresses	connection dns	mutex	http1.1 http2	--ipv4 $URL

--ipv4

This option tells curl to use IPv4 addresses only when resolving hostnames, and not for example try IPv6.