- PKWARE SECUREZIP SERVER ARCHIVE
- PKWARE SECUREZIP SERVER REGISTRATION
- PKWARE SECUREZIP SERVER SOFTWARE
- PKWARE SECUREZIP SERVER CODE
] Reducing is supported for expansion only. In 1990-3, PKZIP 1.1 was released with a new compression algorithm, colourfully referred to as "imploding", which was chosen based on the characteristics of the file being compressed. However, shrinking uses dynamic LZW, which Unisys held patents the patent for the Reduce algorithm had also been filed on June 19, 1984, long before PKZIP had been produced. Although popular at the time, files in PKZIP 1.0 format are now rare, and many modern unzip tools are unable to handle "shrinking" and "reducing", although "imploding" is usually supported. PKZIP 0.9 supports Reducing algorithm with 4 compression settings and shrinking.
PKWARE SECUREZIP SERVER REGISTRATION
It was a DOS command-line tool and was distributed as shareware with a $25 registration fee. The first version of PKZIP appeared in 1989. Cooper's DWC, and LHarc by Haruhiko Okomura and Haruyasu Yoshizaki. Other archivers also appeared during the 1980s, including Rahul Dhesi's ZOO, Dean W.
PKWARE SECUREZIP SERVER SOFTWARE
SEA's ARC was largely abandoned in favor of PKZIP and PKUNZIP as the predominant data compression software on MS DOS.
However, the community largely sided with Katz, and became persuaded by the superior compression capabilities of PKZIP. In fact, at the time, both SEA and PKWARE were small home-based companies. The suit by SEA angered many shareware users, perceiving that SEA was a "large, faceless corporation" and Katz was "the little guy". As a result of the lawsuit, Katz changed the names of his utilities to PKPAK and PKUNPAK, and then developed PKZIP and PKUNZIP, which were based on new and different file compression techniques. Primarily he changed the word length used by the algorithm from 12 bits to 13 bits resulting in a higher compression for typical binary files.
PKWARE SECUREZIP SERVER CODE
It was found during the court case that Katz had used SEA's ARC source code for the majority of the application but had only made code optimizations to increase speed. Katz lost the lawsuit and was forced to pay $62,500 to SEA to cover their legal fees. The competition from Katz did not please SEA, who sued Katz for trademark infringement, as well as copyright infringement as it alleged that Katz had plagiarised sections of the code.
PKWARE SECUREZIP SERVER ARCHIVE
This also allowed the file extractor to be incorporated into the archive file to create self-extracting archives, which could unpack themselves without requiring an external file extraction utility. Unlike SEA, which combined archive creation and archive file extraction in a single program, Katz divided these functions among two separate utilities, reducing the amount of memory needed to run them.
These files worked with the archive file format used by ARC, but were faster than ARC. Later, Phil Katz developed his own shareware utilities, PKARC and PKXARC, to create archive files and extract their contents. The archive files produced by ARC had file names ending in ".ARC" and were sometimes called "arc files" as a result. These utilities were designed to gather a number of separate files into a single archive file for easier copying and distribution.ĭuring the 1980s, the company System Enhancement Associates (SEA) developed a shareware utility called ARC, based on earlier programs such as tar, that not only grouped files into a single archive file but also compressed them to save disk space, a feature of great importance on early personal computers, where space was very limited and modem transmission speeds were very slow. They include the Unix utilities ar, shar, and tar. Previous programs almost certainly existed.īy the 1970s file archiving programs were distributed as standard utilities with operating systems. PKZIP is an acronym for Phil Katz's ZIP program.įile compression routines date back to at least the 1960s: IBM had a compression program called SQUOZE that was commonly used to pack programs on the 7 mainframes as part of the SHARE operating system. PKZIP is an archiving tool originally written by Phil Katz and marketed by his company PKWARE, Inc.
0 kommentar(er)
