)

var (
	confOnce sync.Once // guards init of confVal via initConfVal
	confVal  = &conf{goos: runtime.GOOS}
)

// systemConf returns the machine's network configuration.
func systemConf() *conf {
	confOnce.Do(initConfVal)
	return confVal
}

// initConfVal initializes confVal based on the environment
// that will not change during program execution.
func initConfVal() {
	dnsMode, debugLevel := goDebugNetDNS()