Subject: A Short History of Arching on Micros From: paul@cgh.UUCP (Paul Homchick) Newsgroups: comp.sys.ibm.pc Message-ID: <757@cgh.UUCP> Date: 1 Oct 88 21:35:51 GMT Organization: Chimitt Gilman Homchick, Radnor, PA Lines: 114 A Short History of Compression and Archive-files on Microcomputers In the beginning, there was no need for an archive-file; disks were simply too small to hold more that 90K or so, and you kept what you wanted on a single diskette... or a whole bunch of diskettes. Some time went by and it was a CP/M world, and diskettes were bigger. In 1981 Richard Greenlaw released SQ and USQ, based on Huffman encoding and written in BDS C. This was the first popular compression technique. Greenlaw gave away the binaries and source code. In 1982 Mike Rubenstein released a series of programs written in DRI PL/1 that collected groups of files into a pair of files-- one of them containing a directory structure, and the other the file collection. Mike gave away the binaries. The two-file format was a bit unwieldy, and later in 1982 Gary Novosielski released "LU", or Library Utility (written in BDS C), which provided a single-file method of collecting a number of files together. LBR (Library) files became extremely popular. Gary was featured in an Infoworld article as a beneficial Public Domain luminary. He gave LU away. By 1983 it was getting hard to ignore the IBM PC as programs which weren't written in BASIC started appearing. SQ/USQ was ported by Chuck Forsberg from unix C-source code. LU was ported to the PC by Tom Jennings, from a unix implementation named "lar" (for Library ARchive). Jennings and Forsberg gave these programs away. MSDOS allowed time and date stamping for directory entries, and before long, renegade, non-compatible versions of LU and SQ appeared which supported this feature. Several people interested in promoting continuing standards in the Public Domain/BBS world (Novosielski, Vern Buerg, Cliff Sharp, and Paul Homchick) got together and added downward-compatible time and date stamping to both SQ and LU. Programs supporting this compatibility included NSQ/NUSQ, LU86, LUE, LUU, and LUD. The authors of these programs gave them away. In order to combine the benefits of LBR organization and file compression, people began putting SQueezed files inside of libraries, or SQueezing LBR files, turning them into LQR files. It thus became logical to add an automatic sq/usq module to a LU utility. Vern Buerg added this feature to his LUU and LUE utilities. The next advance came in 1985 when Thom Henderson of System Enhancements Associates (SEA), released his ARC.EXE program. ARC introduced LZW compression (which was in common use in the unix world) to micros. LZW compression gave users much better compaction than the Huffman encoding used in SQueeze programs. ARC files began to displace SQ and LBR files on Bulletin Board systems throughout the land. ARC was distributed as a shareware program, which meant that if you used it, you were supposed to pay for it. SEA also claimed proprietary rights to the program and the format. They weren't giving anything away. ARC-clones eventually appeared. These were usually coded in assembly language and were faster than the standard SEA-ARC program. These clones included: ARCE/ARCA by Vern Buerg (distributed with the permission of System Enhancement Associates), and PKARC/PKXARC from Phil Katz (PKware, which did not have such permission). Buerg's programs were free, with a suggestion that a donation be sent to SEA. PKware was distributed as shareware, just like SEA's ARC. In 1986 Rahul Dhesi released the zoo archiver. It added 13-bit LZW for tighter compression, full pathnames, and a number of other improved features. Highly portable source code was released, and zoo was ported to Unix, VMS, MS-DOS, and Amiga. Dhesi gave away the source code and the binaries. At first, zoo was largely ignored because it was not "ARC compatible." Later events led to this being seen as an advantage. Phil Katz continued to produced new versions of PKARC, finally, in the latter part of 1987, introducing "SQUASHING" which was similar to zoo's 13-bit LZW compression. Although PKARC was no longer "ARC-compatible" it retained the .ARC extension. This caused confusion for novice users and a lot of grief for BBS operators. This policy was regarding by many as "standard busting," and likely was a factor in the litigation that followed in the summer of 1988. By the middle of 1988, Henderson had been marketing ARC commercially for several years. Katz started advertising in the same magazines as SEA, and began to have significant success. From the outside, it appeared that this market was quite financially rewarding. After some negotiations which failed, SEA sued PKware claiming unfair competition and trademark infringement. This led to BBS archiving getting into the trade press again; Henderson and Katz were featured in an Infoworld article as litigants squabbling over proprietary archiving methods. The lawsuit was settled out of court with PKware agreeing to pay some damages to SEA, and to stop marketing ARC-compatible products after January 1, 1989. After this success, SEA's lawyers apparently began contacting authors of other ARC-compatible programs in an effort to protect SEA's trademark. Phil Katz announced that he would develop a 'new', and 'improved' archiver which would have a 'public' file format, but which would, of course, still be a commercial program. A few BBS operators made some statements of support for this new format. Many observers felt that these statements were premature and essentially political in nature, as at the time the statements were made, there was no format or programs to support. Some BBS operators said that ARC had served well, was an established standard, and they would continue to support it. Other BBS operators, tired of lawyers and the entire shareware and commercial jungle, began to endorse Zoo, as the only truly public format and program. This produced a state of confusion where people were unsure of what course future archiving efforts should take. Some people give programs away. Other people make a business out of their programs, and sell and control them. Those who are unable to learn from history are doomed to repeat it. - Paul Homchick UUCP: {allegra | rutgers | uunet} !cbmvax!cgh!paul Chimitt Gilman Homchick, Inc.; One Radnor Station, Suite 300; Radnor, PA 19087