if opts.Trace == nil {
		opts.Trace = func(msg string) {} // Noop if not defined.
	}

	// Unix listener with special TCP options.
	listenCfg := net.ListenConfig{
		Control: setTCPParametersFn(opts),
	}

	for i, serverAddr := range serverAddrs {
		l, e := listenCfg.Listen(ctx, "tcp", serverAddr)
		if e != nil {
			opts.Trace("listenCfg.Listen: " + e.Error())

			listenErrs[i] = e