Simple UDP sample

I’m looking for a simple UDP sample.
I’m a beginner and the Language Reference doesn’t support me with a simple UDP sample.
I want to:
___ I want to find a network participant and identify him.
___ He is located in the same subnet.
___ I have to send three bytes as broadcast by UDP at port 9090.
___ A matching participant answers with 40 bytes.

Can somebody help me?

here is something about broadcast and multicast

If the applications are both made in Xojo. Just use AutoDiscovery it’s based on UDP and has examples in Internet/Networking .

At everything has to be created from scratch. Since I’m not a professional I have a problem with that.
The UDP AutoDiscovery examples in Internet/Networking doesn’t match well for me.
I’m looking forward for more.