golang调用windows api问题 一直返回失败

    advapi32 := syscall.MustLoadDLL("advapi32.dll")

    c := advapi32.MustFindProc("LookupPrivilegeValueW")

    var a Luid

    r1, _, _ := c.Call(uintptr(0), uintptr(unsafe.Pointer(syscall.StringToUTF16Ptr

("SE_SHUTDOWN_NAME"))), uintptr(unsafe.Pointer(&a)))