ARC (file format)

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ARC
File extension:	`.arc .ark .sue`
MIME type:	`application/octet-stream`
Developed by:	System Enhancement Associates
Type of format:	Data compression

ARC is a file format by SEA (System Enhancement Associates) that was very popular before Phil Katz's introduction of the ZIP format. The file format and the program were both called ARC. The ARC program essentially made obsolete the use of combinations of the SQ program to compress files and the LU program to create .LBR archives by combining the functions of both compression and archiving into a single program. ARC compresses multiple files into one - but unlike ZIP, not entire directory trees. The .arc format was the subject of quite a bit of controversy in the 1980s - an important event in the open source debate.

.arc is often also used as a file extension for several different file types that have in common that they are some kind of archive files.

In the late 1980s a dispute arose between SEA, maker of the ARC program, and PKWARE (Phil Katz Software) over the rights to a program named ARC (or PKARC). It quickly expanded into one of the largest controversies the BBS world ever saw.

1 Additional Notes
2 Filename extension
3 MIME-Type
4 See also
5 External links

[edit] Additional Notes

The SEA vs. PKWARE legal case brought trademark/copyright protection, and intellectual property issues to the forefront to those BBS cultures based on IBM/Intel computers. For example, information about the case was disseminated over the Fidonet network, a subset of the BBS scene usually running on IBM/Intel PC hardware in its early years. In retrospect, SEA vs. PKWARE was largely a non-issue to most BBS users outside of Fidonet.

The major players were Thom Henderson of SEA, and Phil Katz of PKWARE. While others were involved, the lines were soon drawn as Henderson vs. Katz. Thom Henderson had previously been known for his work with Fidonet, including organizing the IFNA (International Fidonet Association) and being an editor of FidoNews.

The controversy centered on a program called ARC, released around 1985, which would compress and store groups of files as one file, making it easier and quicker to download programs and support files at once off of BBSes. This archiving software was written at SEA, and the source code was freely available. Because of the ease of use and availability of this program, it quickly became the de facto standard for file archives on Intel-based IBM machines. The crux of the dispute was Phil Katz's release of a program called PKARC, a faster version of ARC with assembler routines. Back then, compiler optimization was not as good as it is now.

In April of 1988, SEA sued Phil Katz and PKWARE for trademark violation, use of the ARC "look and feel", and direct lifting of ARC code. This was one of the first times that a member of the BBS community sued another member, and it was certainly the most publicized and covered of any up to that time.

The debate over this event spread to many parts of Fidonet and other online services such as Compuserve. Calls were made for protests, petitions, renaming of .ARC files to .SUE, and blatant violation of SEA's claims to ownership with the intention of bankrupting the company in legal fees.

Ironically, Henderson's own work in architecting and improving Fidonet were used against him, as the network spread more debates, contentions, and rumors regarding the legal case than he could reasonably be expected to respond to.

Ultimately, SEA was sold to a Japanese company in 1992 and Henderson moved back to Virginia. While the .arc format has fallen out of favor, the .zip format remains in widespread use.

[edit] Filename extension

.arc (all systems)
.ark (adopted by some bulletin boards as a naming convention indicating that the file contained software for CP/M rather than MS-DOS).
.sue (due to all the legal issues)