if b == 0 {
			t.Error("USER32.IsWindow returns FALSE")
		}
		counter++
		return 1 // continue enumeration
	})
	a, _, _ := d.Proc("EnumWindows").Call(cb, 888)
	if a == 0 {
		t.Error("USER32.EnumWindows returns FALSE")
	}
	if counter == 0 {
		t.Error("Callback has been never called or your have no windows")
	}
}

//sys	GetActiveProcessorCount(groupNumber uint16) (ret uint32)
//sys	GetMaximumProcessorCount(groupNumber uint16) (ret uint32)
//sys	EnumWindows(enumFunc uintptr, param unsafe.Pointer) (err error) = user32.EnumWindows
//sys	EnumChildWindows(hwnd HWND, enumFunc uintptr, param unsafe.Pointer) = user32.EnumChildWindows

	procEnumChildWindows                                     = moduser32.NewProc("EnumChildWindows")
	procEnumWindows                                          = moduser32.NewProc("EnumWindows")
	procExitWindowsEx                                        = moduser32.NewProc("ExitWindowsEx")
	procGetClassNameW                                        = moduser32.NewProc("GetClassNameW")