Zoo
Zoo is a compressed archive format developed by Rahul Dhesi. It was one of the many competing archive formats in the 1980s, and was based (originally) on LZW compression. It had some popularity with Open/VMS and Amiga systems, but didn't ultimately win out over ZIP.
Contents |
Discussion
The Zoo software encompassed several different utilities, which were sometimes distributed individually, and which had their own version numbers.
- Zoo - The main program
- Ooz - Extractor
- Booz (Barebones Ooz) - Extractor; some versions can also list files
- Looz (Ooz with List) - Extract/list/execute
- Atoz - Helper utility for converting other formats (ARC, LBR) to Zoo
- Fiz - Analyze damaged Zoo files
- Stuff - File finder
- Sez - Self-Extracting Zoo utility
Compression methods
| ID | Name | Description |
|---|---|---|
| 0 | No packing | Uncompressed |
| 1 | LZD | LZW. A fairly generic LZW implementation, with a dynamic code size from 9 to 13 bits, and two special codes: 256=Clear, 257=Stop. |
| 2 | LZH | LZ77+Huffman. Nearly identical to LHA's "lh5" method. A small difference is that Zoo defines a way to mark the end of data. The format is pretty well documented in the comments in unzoo.c by Martin Schoenert (see below). |
Identification
Files have bytes DC A7 C4 FD at offset 20.
Zoo files typically start with "ZOO ?.?? Archive.", followed by the byte 0x1a, where each "?" is a digit. Regarding this field, the source code says "The contents of the text message are however not used by Zoo and they may be anything."
Related formats
- Zoo filter format
- Zoo Z format
- Brik - same author
Specifications
[Ed. note: The Zoo format information in these documents is not of the highest quality. We haven't found a specification that is reasonably complete and correct.]
- The ZOO Archive File Format from Corion.net, via FileFormat.info
- Archive format info, including ZOO
- ZOO file header format (among other archive types)
Software
- Konvertor
- Zoo - DOS binaries
- v1.20 (1986-09-06)
- v1.21 (1986-09-21)
- v1.40 (1987-01-24): [1] → Shareware_Grab_Bag_1988.zip → 014/zoo140.arc
- v1.41: OS/2 Shareware BBS Full Collection → 08-Other.zip → S12215.ZIP → ZOO.EXE (bare executable)
- v2.00 (~1988-02-06)
- v2.01 (1988-08-25) - Also includes Fiz 2.0 and Stuff 1.0
- v2.10 (1991-07-09)
- Other official Zoo utilities:
- amiga-stuff.com: Archivers - Lists several versions of Zoo for Amiga
- unzoo.c by Martin Schoenert (Does not support LZD.)
- Open-source library in Free Pascal
- Deark
Original(?) source code:
- v1.41 (1987-02-07): ZOO141_C.LZH
- v1.51 (1987-07-12)
- ASME's Mechanical Engineering Toolkit Dec. 1997 → C_LANG/Z150_SRC.LZH
- As posted to Usenet comp.sources.unix 1987-08: [2]
- v2.01 (1988-08-25)
- zoo-2.01.tar.gz
- ASME's Mechanical Engineering Toolkit Dec. 1997 → C_LANG/{Z201SRC1.Z00 + Z201SRC2.Z00}
- Pegasus 2.0 → pegasus/c_2/zoo_src.zip
- v2.10, a.k.a. v2.1 (1991-07-07)
Other source code and packages:
Sample files
- http://cd.textfiles.com/aminet0294/AMINET/UTIL/ARC/ → *.ZOO
- http://cd.textfiles.com/garbo/PC/ → .../*.ZOO
- http://cd.textfiles.com/geminiatari/ZIP/PROGRAM/ → *.ZOO
- dexvert samples — archive/zoo
Links
- Wikipedia: Zoo (file format)
- zooplan1.zip → ZOOPLAN1.TXT - A Zoo Manifesto, by Rahul Dhesi (1986-11-01)
- The zoo Archiver User's Guide, by Bill Davidsen (for Zoo 2.01)
- Zoo man page - Includes a change log going back to v1.71
- Zoo 1.21 → ZOOHSTRY.TXT - Has some historical information about older versions
