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Date: Fri, 23 Apr 2004 23:31:45 -0700
From: Tim Kientzle <kientzle@freebsd.org>
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To: Don Lewis <truckman@freebsd.org>
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cc: current@freebsd.org
Subject: Re: Testing Tar (was Re: bad news for bsdtar..)
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Don Lewis wrote:
> On 23 Apr, Tim Kientzle wrote:
>>Bruce Evans wrote:
>>
>>>At least the -current version of tar skips reading the
>>>data when it is writing to /dev/null.
>>
>>I wonder why it does that?
> 
> This speeds up Amanda quite a bit.  Amanda will run tar with the
> --totals option ...  to plan the best mixture of full and incremental
> backups.

Hmmm... How accurate does such information need to be?

Getting accurate estimates out of bsdtar could be tricky.
(Either bsdtar needs to know a lot more about archive formats
than it does right now, or libarchive needs to have a way
to export this kind of information.)

Tim