WordPress at a glance
function is not described

comment_author_IP() WP 0.71

Displays the IP address of the author of the current comment.

No Hooks.

Return

Null. Nothing.

Usage

comment_author_IP( $comment_ID ) // phpcs:ignore WordPress.NamingConventions.ValidFunctionName.FunctionNameInvalid;
$comment_ID(int/WP_Comment)
WP_Comment or the ID of the comment for which to print the author's IP address.
Default: current comment

Changelog

Since 0.71 Introduced.
Since 4.4.0 Added the ability for $comment_ID to also accept a WP_Comment object.

Code of comment_author_IP() WP 5.5.1

<?php
function comment_author_IP( $comment_ID = 0 ) { // phpcs:ignore WordPress.NamingConventions.ValidFunctionName.FunctionNameInvalid
	echo esc_html( get_comment_author_IP( $comment_ID ) );
}