Subject: Re: Removing GNU tar and GNU cpio from src?
To: None <tech-userlevel@netbsd.org>
From: der Mouse <mouse@Rodents.Montreal.QC.CA>
List: tech-userlevel
Date: 01/27/2003 03:22:14
>>> something inherently solved by 'dump' and 'dump' alone.
>> ...or my tar.  Or probably others;
> I have yet to see a tar that can (by itself) handle what I consider
> one of the fundamentals of a backup system - that it not alter the
> files being backed up in any way at all.

If the filesystem is FFS, and it is run as a user who can read the raw
disk, my tar qualifies (when run with appropriate options, of course).
It can work in either of two modes: either go through the filesystem
for everything except plain files' contents (which it reads from the
raw disk) or go direct to disk for everything.  (The latter also allows
dumping from filesystem images without needing enough privilege to
mount them, incidentally.  By tarring up single files, it also provides
a convenient interface to extracting files from FFS filesystem images.)

It does, of course, have a third mode which goes through the filesystem
for everything, but that doesn't meet your "untouched atime" criterion
(except, as you note, under conditions when lots of programs do).

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