Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!rutgers!rochester!pt.cs.cmu.edu!b.gp.cs.cmu.edu!Ralf.Brown@B.GP.CS.CMU.EDU
From: Ralf.Brown@B.GP.CS.CMU.EDU
Newsgroups: comp.binaries.ibm.pc.d
Subject: Re: ARC/ZOO/ZIP for comp.binaries.ibm.pc
Message-ID: <240be391@ralf>
Date: 1 Mar 89 05:35:29 GMT
Sender: ralf@b.gp.cs.cmu.edu
Lines: 34
In-Reply-To: <480@skep2.ATT.COM>

In article <480@skep2.ATT.COM>, wcs@skep2.ATT.COM (Bill.Stewart.[ho95c]) writes:
}Where can I get a copy of the ZIP file format and compression algos?

The file format and decompression algorithm are included in the PKZ090.EXE
distribution file.

}Are the format and compression algorithm public-domain?
YES

}Does PK promise he won't change the format on us, so we don't
}        end up with the old problem of PKZIP ver n-1 being
}        unable to read files made by PKZIP ver n?  
PK is not alone in this.  ARC v4 couldn't read ARC v5 archives, and ARC v6 can
create archives that are incompatible with v5.

}Is the compression really significantly better than Lempel-Ziv?
YES

}What restrictions does PK place on using his stuff?
}        Money for the code?  Money for using the format?
Code is not available, though PK has promised public-domain example routines.

}Is the source part of the standard distribution, so we can
}        find out what it "really* does?
NO

}Is the format ASCII, or binary?
binary

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