package main import (        "syscall"        "unsafe"        "fmt" ) func abort(funcname string, err int) {        panic(funcname + " failed: " + syscall.Errno(err).Error()) } var (        kernel32, _ = syscall.LoadLibrary("kernel32.dll")        getModuleHandle, _ = syscall.GetProcAddress(kernel32, "GetModuleHandleW")        user32, _ = syscall.LoadLibrary("user32.dll")        messageBox, _ = syscall.GetProcAddress(user32, "MessageBoxW") ) const (        MB_OK                      = 0x00000000        MB_OKCANCEL                = 0x00000001        MB_ABORTRETRYIGNORE        = 0x00000002        MB_YESNOCANCEL             = 0x00000003        MB_YESNO                   = 0x00000004        MB_RETRYCANCEL             = 0x00000005        MB_CANCELTRYCONTINUE       = 0x00000006        MB_ICONHAND                = 0x00000010        MB_ICONQUESTION            = 0x00000020        MB_ICONEXCLAMATION         = 0x00000030        MB_ICONASTERISK            = 0x00000040        MB_USERICON                = 0x00000080        MB_ICONWARNING             = MB_ICONEXCLAMATION        MB_ICONERROR               = MB_ICONHAND        MB_ICONINFORMATION         = MB_ICONASTERISK        MB_ICONSTOP                = MB_ICONHAND        MB_DEFBUTTON1              = 0x00000000        MB_DEFBUTTON2              = 0x00000100        MB_DEFBUTTON3              = 0x00000200        MB_DEFBUTTON4              = 0x00000300 ) func MessageBox(caption, text string, style uintptr) (result int) {        // var hwnd HWND        ret, _, callErr := syscall.Syscall6(uintptr(messageBox), 4,                0, // HWND                uintptr(unsafe.Pointer(syscall.StringToUTF16Ptr(text))), // Text                uintptr(unsafe.Pointer(syscall.StringToUTF16Ptr(caption))), // Caption                style, // type                0,                0)        if callErr != 0 {                abort("Call MessageBox", int(callErr))        }        result = int(ret)        return } func main() {        defer syscall.FreeLibrary(kernel32)        defer syscall.FreeLibrary(user32)        fmt.Printf("Retern: %dn", MessageBox("Done Title", "This test is Done.", MB_YESNOCANCEL)) } func init() {        fmt.Print("Starting Upn") }