Implementing Symlink in go on Windows

symlink_windows_example.go

package main

import (
	"os"
	"syscall"
	"unsafe"
)

var (
	k32                = syscall.MustLoadDLL("kernel32.dll")
	createSymbolicLink = k32.MustFindProc("CreateSymbolicLinkW")
)

func Symlink(oldpath, newpath string) error {

	// look at target and see if it's a file or dir
	st, err := os.Stat(oldpath)
	if err != nil {
		return err
	}

	// CreateSymbolicLink expects a 0 to link a file and 1 to link a dir
	linkType := 0
	if st.Mode() == os.ModeDir {
		linkType = 1
	}

	// do the call
	_, _, callErr := createSymbolicLink.Call(
		uintptr(unsafe.Pointer(syscall.StringToUTF16Ptr(newpath))),
		uintptr(unsafe.Pointer(syscall.StringToUTF16Ptr(oldpath))),
		uintptr(linkType),
	)

	// check for error
	errno, _ := callErr.(syscall.Errno)
	if errno != 0 {
		return callErr
	}

	return nil

}