Is there a way to have one process write something to the database, and that the other process immediately detects this (maybe some kind of trigger?) so that the 2nd process may process this new data, and send data to the browser which is connected to it via the websocket?

Why not polling?

In reply to Re: RPC via mysql when running under websocketd? by Anonymous Monk
in thread RPC via mysql when running under websocketd? by schweini

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