To be notified on "WakeUp" from "Sleep"



I need to be notified inside my console app when the computer "WakeUp"
from "Sleep".
Please note that I cannot run my process as run and I do not need to
write anything, I just need to be notified in some way.
What is the right approach?
What are the right routines/headers to examine?

Thanks a lot for you help,
Marco Bambini

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