Notifier is still a polling mehtod, is there one method purely by trigger or event driven, not by polling

[alex.]

Thanks

[Pnt]

Notifiers have quite a similar behavior with events.

It is not a polling method. Code is not executed until an event occurs (wait on notification).

[tst]

I'm not sure what your question is, but a wait for notification will not poll if you set the timeout to -1. This is almost definitely explained in the help for the function.

[alex.]

If there is multi writer or reader, how to handle it? How to lock the interlink. How to archive the event driven in cornel level.

I just want to find out the internal machnism.

[tst]

I didn't understand what you want to do. Can you describe your desired architecture in more details?

In general, multiple readers and multiple writers require different tools and it varies even more depending on whether you want to keep all the data or whether it can be lossy.

Locking can usually be done with single-element queues or with semaphores, but again, it depends on the desired architecture.