Create InputStream and OutputStream inside CFSocket accept callback on Linux

Hi all,

I've started working on an implementation of (NS)NetService (\), in pure Swift. My goal is to stay close to the version in Cocoa. While I've got an intial working version, I've hit a snag. When publishing a NetService, you can also listen for connections for that service:

let ns = NetService(domain: "local.", type: "_airplay._tcp.", name: "demo", port: 7000)
ns.publish(options: [.listenForConnections])

The NetService's delegate has a method for accepting connections:

    func netService(_ sender: NetService,
                    didAcceptConnectionWith inputStream: InputStream,
                    outputStream: OutputStream)

I've setup a CFSocket for listening and inside the accept callback it creates a CFReadStream and a CFWriteStream using CFStreamCreatePairWithSocket. The problem is that CFNetwork is not available on Linux and probably will never be. So CFStreamCreatePairWithSocket is not available.

So the question is; how to create InputStream and OutputStream inside the accept callback without CFNetwork?