Why can't Unity find IAsyncResult?

Questions & Answers
1

I’m trying to use UDP to do server discovery.
I’m getting the error: 'The type or namespace name IAsyncResult' could not be found.' I've got using System.Net.Sockets;` at the top of my file, and from what I’ve read IAsyncResult is in System namespace.
(and when I mouseover in MonoDevelop, it’s clear that there’s the same problem with AsyncCallback)
What am I doing wrong?

3

If you’ve read that it’s in the System namespace, why aren’t you

using System;

…?

2

using System;