elgg_reset_system_cache()
Reset the system cache by deleting the caches.
elgg_invalidate_simplecache()
Deletes all cached views in the simplecache and sets the lastcache and lastupdate time to 0 for every...
system_message($message)
Display a system message on next page load.
forward($location="", $reason='system')
Forward to $location.
elgg_echo($message_key, $args=array(), $language="")
Given a message key, returns an appropriately translated full-text string.