If a Go program is running on Windows, what is net poller a wrapper over?

In Go on Windows, net poller is a wrapper around system mechanisms for asynchronous input/output, specifically around Windows I/O Completion Ports (IOCP). IOCP is a high-performance mechanism for handling a large number of network and file operations without blocking threads.

The net poller in Go uses IOCP to efficiently wait for input/output events, allowing the Go scheduler to switch goroutines without blocking system threads, which increases the performance and scalability of network applications.