DOS ain't dead

.ARC compression format (Announce)

posted by Rugxulo , Usono, 28.07.2010, 21:27

> > Because ARC had got assassinated before
> correct.

Here's what I know (from reading about it):

Originally IBM PCs were heavily underpowered. But the popular methods to compress stuff (on the non-*nix side) were .LBR ("library", uncompressed archive like tar) and .Q ("squeeze", single-file compressor like gzip). Hence if you look hard enough you'll find .LQR (.LBR + .?Q?) files.

When ARC came around, it was both in one util. It was better compression too (I think??), using LZW (probably inspired from Welch's 1984? Byte magazine article, which neglected to mention patent issues). Well, some people say it crashed occasionally. (I think latest was 6.0 or 7.0, can't rememeber. Sac.sk still has some recent-ish version.) So a fair amount of people used it.

Thom explicitly said (at least later) that ARC was free for personal use. He was a small company, so he had the source open for anyone to port to non-DOS OSes. It was only DOS, commercially, that he wanted to protect. Phil Katz, out of principle, probably thought he shouldn't have to license it. He fought it to court and lost (I think). His main claim to fame was speeding it up with some assembly (PKARC). After that, he made PKPAK and later PKZIP (new format).

Only in PKZIP 0.90 beta (?? or 2.0 ??) did Deflate get supported. Apparently, he dedicated the "new" .ZIP format to the public domain, and he was always open to the Info-Zip group creating their own portable .ZIP rewrite. Most of the later .ZIP enhancements came after he died from PKWARE Inc. and competitor WinZIP (e.g. competing encryption methods, Bzip2 or PPMD or LZMA methods, Zip64, see latest AppNote).

P.S. Note that there is DEARC (written in Turbo Pascal) that will unpack .ARC files, even Katz's "Squash"'d files. (There's also an unpacker in Forth somewhere, but I never tried too hard to get it working.) Vernon Buerg (sadly recently deceased, according to Eric Auer) wrote ARCE, which is a very tiny tool that many enjoyed over the years too.

P.P.S. Bah, I could point to links for a lot of these, but I guess nobody cares or else you can figure it out yourselves.

Complete thread:

• cdrtools_from_Schily - david, 21.07.2010, 21:20 (Announce)
  • cdrtools_from_Schily - Arjay, 21.07.2010, 21:59
    • cdrtools_from_Schily - Rugxulo, 21.07.2010, 22:32
      • cdrtools_from_Schily - Arjay, 21.07.2010, 23:13
        • cdrtools_from_Schily - Rugxulo, 22.07.2010, 01:04
          • cdrtools_from_Schily | NTLFN problem of 7-ZIP | 7-ZIP vs ZIP - DOS386, 23.07.2010, 07:19
            • cdrtools_from_Schily | NTLFN problem of 7-ZIP | 7-ZIP vs ZIP - david, 23.07.2010, 21:10
              • cdrtools_from_Schily | NTLFN problem of 7-ZIP | 7-ZIP vs ZIP - DOS386, 24.07.2010, 12:06
                • cdrtools_from_Schily | NTLFN problem of 7-ZIP | 7-ZIP vs ZIP - david, 24.07.2010, 15:28
                  • cdrtools_from_Schily | NTLFN problem of 7-ZIP | 7-ZIP vs ZIP - DOS386, 24.07.2010, 15:34
              • cdrtools_from_Schily | NTLFN problem of 7-ZIP | 7-ZIP vs ZIP - Rugxulo, 24.07.2010, 19:56
                • cdrtools_from_Schily | NTLFN problem of 7-ZIP | 7-ZIP vs ZIP - Zyzzle, 24.07.2010, 22:51
                  • cdrtools_from_Schily | NTLFN problem of 7-ZIP | 7-ZIP vs ZIP - Rugxulo, 24.07.2010, 23:44
                    • cdrtools_from_Schily | NTLFN problem of 7-ZIP | 7-ZIP vs ZIP - DOS386, 25.07.2010, 06:33
                      • cdrtools_from_Schily | NTLFN problem of 7-ZIP | 7-ZIP vs ZIP - Zyzzle, 25.07.2010, 12:26
                        • fixing p7zip 4.65 to make .ZIP use DOS, not Unix, as host OS - Rugxulo, 27.07.2010, 01:59
                          • fixing p7zip 4.65 to make .ZIP use DOS, not Unix, as host OS - DOS386, 27.07.2010, 02:38
                          • fixing p7zip 4.65 to make .ZIP use DOS, not Unix, as host OS - Zyzzle, 27.07.2010, 03:40
                            • fixing p7zip 4.65 to make .ZIP use DOS, not Unix, as host OS - DOS386, 27.07.2010, 03:49
                          • fixing p7zip 4.65 to make .ZIP use DOS, not Unix, as host OS - Zyzzle, 27.07.2010, 07:23
                        • cdrtools_from_Schily | NTLFN problem of 7-ZIP | 7-ZIP vs ZIP - Arjay, 27.07.2010, 14:31
                • cdrtools_from_Schily | NTLFN problem of 7-ZIP | 7-ZIP vs ZIP - david, 27.07.2010, 08:10
                • cdrtools_from_Schily | NTLFN problem of 7-ZIP | 7-ZIP vs ZIP - david, 27.07.2010, 14:34
      • cdrtools_from_Schily - david, 22.07.2010, 07:48
    • cdrtools_from_Schily - david, 22.07.2010, 07:52
      • cdrtools_from_Schily - Arjay, 27.07.2010, 15:54
        • p7zip p7zip p7zip ... - Rugxulo, 27.07.2010, 16:46
          • p7zip p7zip p7zip ... - Arjay, 27.07.2010, 18:09
            • p7zip p7zip p7zip ... - Rugxulo, 28.07.2010, 02:28
              • p7zip p7zip p7zip ... - Arjay, 28.07.2010, 08:02
            • p7zip pp7zipp ppp7zippp ... stupidity goes on - DOS386, 28.07.2010, 03:23
              • p7zip pp7zipp ppp7zippp ... stupidity goes on - Arjay, 28.07.2010, 08:07
                • .ARC compression format - Rugxulo, 28.07.2010, 21:27
                • p7zip pp7zipp ppp7zippp ... stupidity goes on | UI21DEB used - DOS386, 29.07.2010, 05:56
                  • p7zip pp7zipp ppp7zippp ... stupidity goes on | UI21DEB used - DOS386, 29.07.2010, 05:58
                    • p7zip pp7zipp ppp7zippp ... stupidity goes on | UI21DEB used - DOS386, 29.07.2010, 06:05
                      • p7zip pp7zipp ppp7zippp ... stupidity goes on | UI21DEB used - Rugxulo, 29.07.2010, 08:37
                      • p7zip pp7zipp ppp7zippp ... stupidity goes on | UI21DEB used - DOS386, 31.07.2010, 07:53
                  • p7zip pp7zipp ppp7zippp ... stupidity goes on | UI21DEB used - Khusraw, 29.07.2010, 09:21
          • p7zip p7zip p7zip ... - Zyzzle, 28.07.2010, 08:22
            • p7zip p7zip p7zip ... - Rugxulo, 28.07.2010, 21:14
              • p7zip p7zip p7zip ... - Arjay, 01.08.2010, 12:05