Path: utzoo!utgpu!attcan!uunet!lll-winken!lll-ncis!lll-lcc!ames!nrl-cmf!ukma!rutgers!bellcore!faline!thumper!ulysses!andante!alice!debra
From: debra@alice.UUCP (Paul De Bra)
Newsgroups: comp.unix.wizards
Subject: Re: GNU-tar vs dump(1)
Message-ID: <8768@alice.UUCP>
Date: 15 Jan 89 21:38:37 GMT
References: <17999@adm.BRL.MIL> <629@mks.UUCP> <11@estinc.UUCP> <10797@rpp386.Dallas.TX.US> <1966@netmbx.UUCP> <6099@polya.Stanford.EDU> <15@estinc.UUCP>
Reply-To: debra@alice.UUCP ()
Organization: AT&T, Bell Labs
Lines: 26

In article <15@estinc.UUCP> fnf@estinc.UUCP (Fred Fish) writes:
>In article <6099@polya.Stanford.EDU> weening@Gang-of-Four.Stanford.EDU (Joe Weening) writes:
>>One thing that worries me about using tar for dumps is that it updates
>>the access time of all the files that it reads.  Is there any way to
>>avoid this?
>
>Yes, it is possible, but it has other side effects that are undesirable.
> [long explanation deleted]

Several backup programs have started using "ctime" instead of "mtime",
assuming that this guarantees that whatever a user does to his files they
will be backed up.

Unfortunately this does not work: if one renames a directory none of the
attributes of the files in this directory change. So the files are not
backed up and unless one knows the previous name of the directory one
cannot find the files in the backup again. Try "rm *" accidently and then
recover the files from backup... Unless you still know the previous name
of the directory and/or the names of the files you want to recover you
won't find the files...

Paul.
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