test.go

package main

import (
	"fmt"
	"log"
	"os/exec"
	"runtime"

	"golang.org/x/sys/windows/registry"
)

// OS is an interface for all OS's
type OS interface {
	doSomething()
}

type windows struct{}
type linux struct{}

// WINDOWS

func (w windows) doSomething() {

	regKey, err := registry.OpenKey(registry.CURRENT_USER, `Control Panel\Desktop`, registry.QUERY_VALUE)
	if err != nil {
		log.Fatal(err)
	}
	defer regKey.Close()

	ssa, _, errSSA := regKey.GetStringValue("ScreenSaveActive")
	if errSSA != nil {
		log.Fatal(errSSA)
	}
	fmt.Printf("Screensaver is %q\n", ssa)
}

// LINUX

func (l linux) doSomething() {

	out, err := exec.Command("uuidgen").Output()
	if err != nil {
		log.Fatal(err)
	}

	fmt.Printf("%s", out)
}

// CHECK OS ON DEVICE POLICIES
func check(o OS) {
	o.doSomething()
}

func main() {
	switch os := runtime.GOOS; os {
	case "windows":
		osType := windows{}
		check(osType)
	case "linux":
		osType := linux{}
		check(osType)
	}
}