Path: utzoo!utgpu!watmath!uunet!uvm-gen!banzai!roger
From: roger@banzai.UUCP (Roger Florkowski)
Newsgroups: unix-pc.general
Subject: Re: Keyboard Cables?
Keywords: Where?  Tape Backups?
Message-ID: <1074@banzai.UUCP>
Date: 28 Jan 89 02:16:32 GMT
References: <7454@ihlpf.ATT.COM>
Reply-To: roger@banzai.UUCP (Roger Florkowski)
Distribution: unix-pc
Organization: People's Computer Company, Williston, VT
Lines: 29

In article <7454@ihlpf.ATT.COM> gmark@ihlpf.ATT.COM (Stewart) writes:
>
>And, finally, does anyone have any information regarding the
>algorithm used by the 3B1 to backup?  I assume a complete
>backup saves the entire hard disk which, considering that
>so much of it is from the foundation disks and other UNIX
>stuff already on the owner's floppies, is quite a waste!
>
>[deleted]... Has anyone
>tried to change the "last-partial-backup" date to cause only any
>files changed AFTER the initial software installation to
>be saved for backing up?
>

A "complete" backup only backs up those files that are newer
than /etc/.installdate,  therefor, it does NOT backup the foundation
set.   The first "complete" backup then sets /etc/.lastbackup,
which "partial backup" works off of.  It 'knows' that a Complete
backup hasn't been done if /etc/.lastbackup is missing.
This works the same for both Tape backups and floppy backups.

for those hackers, look in:

/usr/bin/Backup.sh	[for floppy backups]
/usr/bin/Tbackup.sh	[for Tape backups]

-- 
Roger Florkowski	       		{uunet!uvm-gen, attmail}!banzai!roger
The People's Computer Company			  `Revolutionary Programming'