WordPress at a glance
function is not described

wp_cache_close() WP 2.0.0

Closes the cache.

This function has ceased to do anything since WordPress 2.5. The functionality was removed along with the rest of the persistent cache.

This does not mean that plugins can't implement this function when they need to make sure that the cache is cleaned up after WordPress no longer needs it.

No Hooks.

Return

true. Always returns true.

Usage

wp_cache_close();

Code of wp cache close: wp-includes/cache.php VER 5.0.3

<?php
function wp_cache_close() {
	return true;
}