test.cs

var tc = new TcpClient();
tc.Connect("irc.freenode.net", 6697);
var ssl = new SslStream(tc.GetStream());
ssl.AuthenticateAsClient("irc.freenode.net");
var reader = new StreamReader(ssl, Encoding.UTF8);
var writer = new StreamWriter(ssl, Encoding.UTF8);

writer.WriteLine("CAP LS 302");
var sockets = new[] { tc.Client };
while (true) {
    Socket.Select(sockets, null, null, -1);
    while (tc.Client.Available > 0) {
        reader.ReadLine().Dump();
    }
}
// output
:verne.freenode.net NOTICE * :*** Looking up your hostname...
:verne.freenode.net NOTICE * :*** Checking Ident
:verne.freenode.net NOTICE * :*** Found your hostname
:verne.freenode.net NOTICE * :*** No Ident response
<timeout>