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Date:      Mon, 06 Mar 1995 00:25:23 -0800
From:      "Justin T. Gibbs" <gibbs@estienne.CS.Berkeley.EDU>
To:        "Jordan K. Hubbard" <jkh@freefall.cdrom.com>
Cc:        Brian Tao <taob@gate.sinica.edu.tw>, "Jordan K. Hubbard" <jkh@FreeBSD.org>, current@freefall.cdrom.com
Subject:   Re: "Sparse" files? 
Message-ID:  <199503060825.AAA12037@estienne.cs.berkeley.edu>
In-Reply-To: Your message of "Sun, 05 Mar 1995 23:12:55 PST." <24592.794473975@freefall.cdrom.com> 

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>>     I thought ffs could already compress sparse files?  Apple II ProDOS 
>> does this, but it isn't strictly "compression".  I think it simply 
>> doesn't bother to allocate disk blocks for any that are completed filled 
>> with null bytes.  There's no performance hit, and this is on floppy-bound
>> 1-MHz //e's and //c's... :)
>
>I don't think it does it on-the-fly, no.  Bruce pretty much clinched
>it when he pointed out that GNU cp, which linux uses by default,
>automatically creates the holes and so their executables "compress" as
>they're installed (or moved elsewhere).  GNU tar also has support for
>this and they probably leave the flag on (--sparse) by default.
>
>But as Bruce also points out, our block size of 8K also makes this
>kind of compression scheme much less likely to be effective.
>
>					Jordan

Is there anyway to take advantage of our 1K frag size for doing this?

--
Justin T. Gibbs
==============================================
TCS Instructional Group - Programmer/Analyst 1
  Cory | Po | Danube | Volga | Parker | Torus
==============================================



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