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seek in a zip file??

hello all!
i´m working with big size files, to maintain them, it would be better to
compress the files.
to recover a little part of the big file, how can i extract that little
parte instead of the whole file that will bring a lot of time?
Can i know the offset in a zip file?? i know the offset in the big one.
Any idea will be welcome.

Thanks.

Enrique
Madrid- Spain

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Jul 18 '05 #1
2 4050
Enrique <en************@xgs-spain.com> wrote:
hello all!
i´m working with big size files, to maintain them, it would be better to
compress the files.
to recover a little part of the big file, how can i extract that little
parte instead of the whole file that will bring a lot of time?
Can i know the offset in a zip file?? i know the offset in the big one.
Any idea will be welcome.


I used dictzip for the same purpose, and it works well.
download serpento from
http://melkor.dnp.fmph.uniba.sk/~garabik/serpento/
and look for dictzip module
(compress the files with dictzip from dictd package)

--
-----------------------------------------------------------
| Radovan GarabÃ*k http://melkor.dnp.fmph.uniba.sk/~garabik/ |
| __..--^^^--..__ garabik @ kassiopeia.juls.savba.sk |
-----------------------------------------------------------
Antivirus alert: file .signature infected by signature virus.
Hi! I'm a signature virus! Copy me into your signature file to help me spread!
Jul 18 '05 #2
"Enrique" <en************@xgs-spain.com> wrote in message news:ma************************************@python .org...
hello all!
i´m working with big size files, to maintain them, it would be better to
compress the files.
to recover a little part of the big file, how can i extract that little
parte instead of the whole file that will bring a lot of time? It's impossible by design of zip compression algorithm.
Can i know the offset in a zip file?? i know the offset in the big one.
Any idea will be welcome.

Pack your file in small chunks (for example 256K) and hide
this fact from your main program using small wrapper.
Or use file system compression (available on windows ntfs filesystem)
Or find a compression library that allows random access
and generate a wrapper for it using SWIG.
Jul 18 '05 #3

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