[Conclusion] tar and --sparse

[T o n g <mlist4suntong@yahoo.com>]

Hi, 

Thanks you all for the comments, which make it obligatory for me to 
explain more. First, why I asked:

 $ man tar | grep -i sparse
     -S, --sparse
           handle sparse files efficiently
     --sparse-version=MAJOR[.MINOR]
           set version of the sparse format to use (implies --sparse)

On Wed, 22 Sep 2010 22:59:38 +0200, Sven Joachim wrote:

>> I created a Linux system tar ball without using the --sparse switch.
>> The .tar.bzip2 tar ball is only of 1.5G in size. However, restoring
>> such tar ball into a 10G partition would fail:
>>
>>  Cannot write: No space left on device
>>
>> . . .
> 
> The GNU tar documentation says this about the --sparse option:
> 
>      This option is meaningful only when creating or updating archives.
>      It has no effect on extraction.

I think this explains well. 

IIRC, the source is only around 3G, at most 5G, according to du output. 
But it turns out I need over 15G of space to expand this 1.5G tar ball. 
Sparse files are the reason.

cheers

-- 
Tong (remove underscore(s) to reply)
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