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CC:	
Subj:	RE: modifying file date

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From: MNK@RDAC.dnet.hac.com          (Mike Kimura)
To: ax@hac2arpa.hac.com, leichter@lrw.com@arpa.DECNET
Subject: RE: modifying file date

	Jerry wrote...

>Here's the simplest "touch" command I know of:
>
>	$ touch :== SET FILE/BACKUP
>
>The only time this fails is in the unlikely case that you want to touch a file
>that is set /NOBACKUP.  (It will, of course, end up being set /BACKUP.)  Not
>a big problem, in my experience - AND you get the advantage of wild-carding
>and all the standard file selection mechanisms (/CREATED/BEFORE, /BY_OWNER,
>etc.) for free.

	I prefer the similar command (dare I differ with Jerry?):

	$ touch :== SET FILE/NOEXPIRATION_DATE

	This will update the revision date/time to the current date/time
	with all the same advantages as SET FILE/NOBACKUP stated above.

	If the volume has a retention period specified then the expiration
	date will get set to the current time + max which is the desirable
	behavior if you "touch" the file. If the volume does not have a
	retention period specified, then the expiration date will get set
	to "none" (17-NOV-1858 00:00:00.00) which is probably what it was
	originally since the volume didn't have a retention period.

	/NOEXPIRATION_DATE seems a bit less failure prone then /BACKUP
	since if you were using /BACKUP someone could accidentally issue
	TOUCH *.* forget they were in SYS$SYSTEM and end up enabling
	BACKUPs on the page/swap/dump files.

	Mike
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Michael Kimura			
Hughes Aircraft Company (RSG)	Internet:	mnk@rdac.dnet.hac.com
P.O. Box 92426	  MS: R2/9A37	EDEN:		RDAC::MNK
Los Angeles,  CA  90009		Telephone:	(213) 615-9775
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