How to get a signal about the publication of a post on someone else's vk.com page?

Question

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If possible, some examples.
Authorization is not interested in the example of how to get a page with sockets or something else without a every second update.

Answer 1

API? we get the last post on the wall (we take its ID), periodically send a request to check the last post on the wall, if the id has changed, we notify and replace our current id with the new one received.