Zoo (file format)
From Wikipedia, the free encyclopedia
| zoo | |
|---|---|
| File name extension | .zoo |
| Type of format | data compression |
zoo is a compression program and format developed by Rahul Dhesi in the mid 1980s. The format is based on the LZW compression algorithm and compressed files are identified by the .zoo file extension. It is no longer widely used. Program source code was originally published on the comp.sources.misc Usenet newsgroup, and was compatible with a variety of Unix-like operating systems. Binaries were also published for the MS-DOS user community. A small companion program was also developed, entitled booz, that provides only decompression functionality.
The .ZOO file format was mostly popular with Digital (now Hewlett Packard) VAX computers running the OpenVMS operating system, and for a time with the Commodore Amiga community.
[edit] Technical Specification
| Decimal Offset |
Hex Offset |
Size in Bytes |
Description |
|---|---|---|---|
| 000-019 | 000-013 |
|
Archive header text, padded with nulls, terminated by ^Z |
| 020-023 | 014-017 |
|
Hex string A7DCFDC4 |
| 024-027 | 018-01B |
|
Offset of first file in archive |
| 028-031 | 01C-019 |
|
Offset of first file in archive - 1 |
| 032 | 020 |
|
Version of ZOO this Archive was created by |
| 033 | 021 |
|
Minimum Version of ZOO needed to extract files from archive |
| Decimal Offset |
Hex Offset |
Size in Bytes |
Description |
|---|---|---|---|
| 000-003 | 000-003 |
|
Hex string A7DCFDC4 |
| 004 | 004 |
|
Type of directory entry |
| 005 | 005 |
|
Compression method; 0 - Stored without compression; 1- Crunched (LZW) |
| 006-009 | 006-009 |
|
Offset of next directory entry |
| 010-013 | 00A-00C |
|
Offset of next header |
| 014-016 | 00D-011 |
|
Original date and time of file |
| 017-018 | 012-013 |
|
CRC-16 of file |
| 019-022 | 014-017 |
|
Uncompressed file size |
| 023-026 | 018-01B |
|
Compressed file size |
| 027 | 01C |
|
Version of ZOO by which this file was compressed |
| 028 | 01D |
|
Minimum version of ZOO needed to extract this file |
| 029 | 01E |
|
Deleted flag: 0-File is present; 1-file is marked as deleted |
| 030 | 01F-022 |
|
Offset to file comment field or 0 if no comment |
| 031-032 | 023-024 |
|
Length of comment field |
| 033+ | 025+ | Variable | File name, which may include a path, null terminated |
[edit] Other uses
The file format .zoo are also saved zoos for Microsoft's Zoo Tycoon PC game.
[edit] External links
- zoo 2.10 source
- unzoo - zoo archive extractor, source included

