Detect windows version in Go to figure out the starup folder

Is there anyway to detect if the host operating system is XP, Vista, 7, 8, or 10?
runtime.GOOS just returns "windows".

The reason for this is because I'm trying to manipulate files in the startup folder.

On windows vista, 7, 8, 10 it's located at:

%appdata%\Roaming\Microsoft\Windows\Start Menu\Programs\Startup

On windows XP it's located at:

Documents and Settings\%username%\Start Menu\Programs\Startup

Why not use the windows registry?

https://godoc.org/golang.org/x/sys/windows/registry

https://stackoverflow.com/questions/36998532/how-to-return-a-default-value-from-windows-registry-with-golang

package main

import (
	"golang.org/x/sys/windows/registry"
	"log"
	"fmt"
)

func main() {

	k, err := registry.OpenKey(registry.LOCAL_MACHINE, `SOFTWARE\Microsoft\Windows NT\CurrentVersion`, registry.QUERY_VALUE)
	if err != nil {
		log.Fatal(err)
	}
	defer k.Close()

	cv, _, err := k.GetStringValue("CurrentVersion")
	if err != nil {
		log.Fatal(err)
	}
	fmt.Printf("CurrentVersion: %s\n", cv)

	pn , _, err := k.GetStringValue("ProductName")
	if err != nil {
		log.Fatal(err)
	}
	fmt.Printf("ProductName: %s\n", pn)

	maj, _, err := k.GetIntegerValue("CurrentMajorVersionNumber")
	if err != nil {
		log.Fatal(err)
	}
	fmt.Printf("CurrentMajorVersionNumber: %d\n", maj)

	min, _, err := k.GetIntegerValue("CurrentMinorVersionNumber")
	if err != nil {
		log.Fatal(err)
	}
	fmt.Printf("CurrentMinorVersionNumber: %d\n", min)

	cb, _, err := k.GetStringValue("CurrentBuild")
	if err != nil {
		log.Fatal(err)
	}
	fmt.Printf("CurrentVersion: %s\n", cb)    
}

This returns:

PS C:\Users\Adamar\Desktop> .\WindowsVersion.exe
CurrentVersion: 6.3
ProductName: Windows Server 2016 Standard Evaluation
CurrentMajorVersionNumber: 10
CurrentMinorVersionNumber: 0
CurrentVersion: 14393

Although in the newest version of windows you have to read the following keys to get the version: CurrentMajorVersionNumber & CurrentMinorVersionNumber

If you want to get the Windows version, use the w32 library, a pure Go Win32 API wrapper.

It has w32.RtlGetVersion() which returns a struct containing (besides other things) MajorVersion and MinorVersion. These will report the correct Windows version that the program is running on.

You cannot rely on the function w32.GetVersion(). Theoretically you could use this Windows version table to know where you are but GetVersion only works for applications that have a correct manifest file which says that the program is for Windows 10. If you just compile with go build without a manifest file, GetVersion will still report Windows 8 (Windows version 6.2).

package main

import (
	"fmt"
	"github.com/gonutz/w32/v2"
)

func main() {
	v := w32.RtlGetVersion()
	fmt.Println(v.MajorVersion, v.MinorVersion)
}

Note however, as others have stated correctly, that you should really be using the appropriate Win32 API functions to get the special folders in your case.

I know that this is old, but at the time of this writing (Jan 2023), you can use RtlGetNtVersionNumbers, which is officially maintained by Go.

package main

import (
	"fmt"

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

func main() {
	maj, min, patch := windows.RtlGetNtVersionNumbers()
	fmt.Println(maj, min, patch)
}

which for me prints 10 0 22621.

Based on excellent on-point comments from Jörg W Mittag, this should make you started:

//go:build windows

package main

import (
	"fmt"

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

func main() {
	path, err := windows.KnownFolderPath(windows.FOLDERID_Startup, 0)
	fmt.Println(err, path)
}

See syscall_windows.go and zknownfolderids_windows.go at <https://cs.opensource.google/go/x/sys/+/master:windows> for more info.

Note that the last version of Go to support WinXP was 1.10, the current one is 1.19, and the support is provided for the two last versions, hence the last supported version as of now, 2023-01-10, is 1.18.
I mean, the need to make it work on WinXP is moot: a program built for Windows using Go 1.14+ won't even start on that platform.