From: Mathieu Bouchard Date: 2002-01-22T14:48:36+09:00 Subject: Re: zip on Linux On Tue, 22 Jan 2002, Eric Lee Green wrote: > >> This was somewhere around 1991, if I recall correctly. Note that pkzip > >> arguably violates the Unisys patent since it uses basically the same > >> compression algorithm as 'arc', which is basically the same > >> compression algorithm as 'compress', > > well, there is pkzip 1 ('89) and pkzip 2 ('93). Pkzip 1 did compress > > significantly better than arc; > Any references to that? I was rummaging around and it looked like > pkzip 1 was arc with the serial numbers filed off. er, as i remember it, in 1992 i downloaded PKZIP 1, PKPAK, PKARC, SEAARC, and a few others, and tried them all. PKPAK was a mere renaming of PKARC; PKARC was format-compatible with SEAARC both ways, although PKARC did compress better (!!!). PKZIP 1.x was incompatible and combined 5 methods (?) where the most powerful was the most often used, and the others were useful for special cases. PKZIP 2.x introduced a new compression method which made all others obsolete. I remember that I mostly cared about the file size; i rarely compared their times at all and I don't remember those. > > Pkzip 2 is significantly better than Pkzip > > 1, and extremely similar to GZip in performance (normally +/- 1%); which > gzip is a very slow compression program, BTW. Sorry, I meant compression ratio. > Hmm, care to mention one that compresses tighter than bzip2? see: http://compression.ca/act-win.html > > I don't see bz2 replacing gzip, because bz2 compression is not streamable. > ? Most people use gzip or bzip2 in the context of compressing tarballs. I wouldn't aim for "most", I would aim for "almost all". > What advantages? People talk about the ability to retrieve a random file > from a zip archive. Guess what -- I have *NEVER* done that. Yeah, and so what? (this is not a question) ________________________________________________________________ Mathieu Bouchard http://hostname.2y.net/~matju