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From: dwd@ttrda.UUCP (Dave Dykstra )
Newsgroups: net.bugs.usg
Subject: A good incremental backup for system V
Message-ID: <151@ttrda.UUCP>
Date: Mon, 21-Apr-86 10:51:00 EST
Article-I.D.: ttrda.151
Posted: Mon Apr 21 10:51:00 1986
Date-Received: Wed, 23-Apr-86 21:13:01 EST
Organization: AT&T, Computer Systems Division, Skokie, IL
Lines: 25

I now see that a good incremental backup for system V is possible.

> As has been known at least since the V7 dump/restor system was written
> (1978?), you should dump based on the most recent of the mod time and
> the change time.  The change time changes when the inode changes, and
> since a rename involves (temporarily) changing the link count, the change
> time will reflect it.

With the above suggestion of Henry Spencer, I put in a quick addition to
find(1) to look for files that are newer based on change time instead of
modification time, calling the option '-cnewer'.  Now all I need is
the change to cpio that was formerly suggested to have an option to
remove files which no longer exist.  All it needs to do (I think) is
to save the complete contents of directories which have been changed
and unlink the files which aren't in the directories upon restore.

> I'm planning to post afio, my homegrown cpio replacement, to mod.sources
> Real Soon Now*. Among its excessive features are automatic recognition of
> ASCII, binary and byte-swapped binary cpio archives. There are many other
> neat things; the present manual page follows.

How about adding the option to afio, Mark Brukhartz?  

			- Dave Dykstra @ AT&T Teletype
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