ファイルオープン時の装置番号処理

Unit number handling at file open

Authors:	Yasuhiro MORIKAWA
Version:	$Id: dc_iounit.f90,v 1.2 2007/07/11 13:58:41 morikawa Exp $
Tag Name:	$Name: gt4f90io-20080210 $
Copyright:	Copyright (C) GFD Dennou Club, 2007. All rights reserved.
License:	See COPYRIGHT

This file provides following module.