THPDFDocumentHandlerStatus Type
THPDFDocumentHandlerStatus = (
dhsNotRun, dhsSucceeded, dhsNoHandler, dhsInvalidOptions,
dhsInvalidSource, dhsUnsupportedContent, dhsBudgetExceeded,
dhsCancelled, dhsHandlerFailed, dhsDestinationFailed
);認識、検証、予算、キャンセル、ハンドラ、宛先の各結果を区別するため、想定内の失敗に例外は必要とされません