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Date: Wed, 02 Aug 2006 08:45:25 -0700
From: Tim Kientzle <kientzle@freebsd.org>
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To: Peter Jeremy <peterjeremy@optushome.com.au>
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Cc: freebsd-hackers@freebsd.org
Subject: Sparsifying Files (was Re: [PATCH] adding two new options to 'cp')
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Peter Jeremy wrote:
> As a general comment (not addressed to Tim):  There _is_ a downside
> to sparsifying files.

How people use (or misuse) such a feature is just
not my concern.  I've not seen anyone
on this thread suggest that such sparsification
be done by default, and there are certainly rare
situations where sparsification is useful.

The tar implementation is about 95% system-independent
file format work and 5% system-dependent hole mapping.
The mapping process is the easy part.  (And therefore,
for me, the least interesting part.)  A system call could
make it accurate, but it's not enough code to
fuss over either way.

Tim