Execute an event from the server by itself

Hi,

How can I execute an event from the server by itself?

What I mean is something like the timer, that on the specified interval it execute itself and it refresh the page.

I don?t know if is possible because I haven?t work on it yet, but what I want is to have something like a loop or whatever watching some settings and when the settings change on the server refresh the page with a message on it.

I don?t want to use a timer because even if no changes have been applied to the settings the page will be refreshed any way.

Any idea or solution will be appreciated.
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