WordPress at a glance
function is not described

wp_clear_auth_cookie() WP 2.5.0

Removes all of the cookies associated with authentication.

This is a pluggable function, and it can be replaced by a plugin. It means that this function is defined (works) only after all plugins are loaded (included), but before this moment this function has not defined. Therefore, you cannot call this and all functions depended on this function directly from a plugin code. It must be called on plugins_loaded hook or later, for example on init hook.

Function replacement (override) — in a plugin you can create a function with the same name, then it replace this function.

Hooks in function
Return

Nothing (null).

Usage

wp_clear_auth_cookie();

Code of wp clear auth cookie: wp-includes/pluggable.php VER 5.1.1

<?php
function wp_clear_auth_cookie() {
	/**
	 * Fires just before the authentication cookies are cleared.
	 *
	 * @since 2.7.0
	 */
	do_action( 'clear_auth_cookie' );

	/** This filter is documented in wp-includes/pluggable.php */
	if ( ! apply_filters( 'send_auth_cookies', true ) ) {
		return;
	}

	// Auth cookies
	setcookie( AUTH_COOKIE, ' ', time() - YEAR_IN_SECONDS, ADMIN_COOKIE_PATH, COOKIE_DOMAIN );
	setcookie( SECURE_AUTH_COOKIE, ' ', time() - YEAR_IN_SECONDS, ADMIN_COOKIE_PATH, COOKIE_DOMAIN );
	setcookie( AUTH_COOKIE, ' ', time() - YEAR_IN_SECONDS, PLUGINS_COOKIE_PATH, COOKIE_DOMAIN );
	setcookie( SECURE_AUTH_COOKIE, ' ', time() - YEAR_IN_SECONDS, PLUGINS_COOKIE_PATH, COOKIE_DOMAIN );
	setcookie( LOGGED_IN_COOKIE, ' ', time() - YEAR_IN_SECONDS, COOKIEPATH, COOKIE_DOMAIN );
	setcookie( LOGGED_IN_COOKIE, ' ', time() - YEAR_IN_SECONDS, SITECOOKIEPATH, COOKIE_DOMAIN );

	// Settings cookies
	setcookie( 'wp-settings-' . get_current_user_id(), ' ', time() - YEAR_IN_SECONDS, SITECOOKIEPATH );
	setcookie( 'wp-settings-time-' . get_current_user_id(), ' ', time() - YEAR_IN_SECONDS, SITECOOKIEPATH );

	// Old cookies
	setcookie( AUTH_COOKIE, ' ', time() - YEAR_IN_SECONDS, COOKIEPATH, COOKIE_DOMAIN );
	setcookie( AUTH_COOKIE, ' ', time() - YEAR_IN_SECONDS, SITECOOKIEPATH, COOKIE_DOMAIN );
	setcookie( SECURE_AUTH_COOKIE, ' ', time() - YEAR_IN_SECONDS, COOKIEPATH, COOKIE_DOMAIN );
	setcookie( SECURE_AUTH_COOKIE, ' ', time() - YEAR_IN_SECONDS, SITECOOKIEPATH, COOKIE_DOMAIN );

	// Even older cookies
	setcookie( USER_COOKIE, ' ', time() - YEAR_IN_SECONDS, COOKIEPATH, COOKIE_DOMAIN );
	setcookie( PASS_COOKIE, ' ', time() - YEAR_IN_SECONDS, COOKIEPATH, COOKIE_DOMAIN );
	setcookie( USER_COOKIE, ' ', time() - YEAR_IN_SECONDS, SITECOOKIEPATH, COOKIE_DOMAIN );
	setcookie( PASS_COOKIE, ' ', time() - YEAR_IN_SECONDS, SITECOOKIEPATH, COOKIE_DOMAIN );

	// Post password cookie
	setcookie( 'wp-postpass_' . COOKIEHASH, ' ', time() - YEAR_IN_SECONDS, COOKIEPATH, COOKIE_DOMAIN );
}