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Re: ramblings about old hardware, gzip, bz2, and pentium opts

On Tue, Nov 30, 1999 at 11:31:07AM +1100, Drake Diedrich wrote:
>    On the bzip/gzip issue I think people should be aware that Andrew
> Tridgell has a plan to make gzipped data rsyncable, using relatively small
> gzip blocks divided by a rolling checksum (rather than a fixed blocklength). 
> All packages would need to be recompressed to get the
> rolling blocks though.
>    On implementing this capability: 
> gzip would need to do the rolling blocks (not yet done).

I don't know exactly, if what rolling blocks mean, but perhaps you could
look at dict(un)zip, which is included in the dictd package. This is
from the beginning of the dictzip manpage:

       dictzip  compresses  files  using  the  gzip(1)  algorithm
       (LZ77) in a manner which is completely compatible with the
       gzip file format.  An extension to the  gzip  file  format
       (Extra  Field,  described  in of RFC 1952) allows
       extra data to be stored in  the  header  of  a  compressed
       file.   Programs like gzip and zcat will ignore this extra
       data.  However, dictd(8),  the  DICT  protocol  dictionary
       server will make use of this data to perform pseudo-random
       access on the file.

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