begin
  repeat
    Result := ZR_Rd_GetNextMessage(g_hRd, nMsg, nMsgParam);
    if Result <> S_OK then
      break;
    case nMsg of
      ZR_RN_CARD_INSERT:
      begin
        pInfo := PZr_Card_Info(nMsgParam);
        ASSERT(pInfo <> nil);
        Writeln(format('Card insert: %s %s', [
            CardTypeStrs[pInfo.nType], ZKeyNumToStr(pInfo.nNum, pInfo.nType)]));
{-----} Writeln(format('Card insert: %s %s', [
            CardTypeStrs[pInfo.nType], ZKeyNumToStr(pInfo.nNum, pInfo.nType)]));
            
      end;
      ZR_RN_CARD_REMOVE:
      begin
        pInfo := PZr_Card_Info(nMsgParam);
        ASSERT(pInfo <> nil);
{-----} Writeln(format('Card removed: %s %s', [
            CardTypeStrs[pInfo.nType], ZKeyNumToStr(pInfo.nNum, pInfo.nType)]));
      end;
    end;
  until False;
  if Result = ZP_S_NOTFOUND then
    Result := S_OK;
end;