LIF (Knowledge Dynamics)
.LIF is an installer-archive format, apparently associated with INSTALL for DOS, by Knowledge Dynamics Corporation. See RED (Knowledge Dynamics) for more information about INSTALL.
This article covers the LIF format that begins with a string of ASCII-encoded hex digits. Note that the presumed successor format, RED, also sometimes uses the .LIF filename extension.
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Format details
File structure
A LIF file consists of a sequence of member file segments. Each member consists of a 54-byte header, then the file data, which is usually compressed.
The header starts with 34 bytes of ASCII-encoded hex digits. A filename follows. The bytes at offset 8 through 15 encode the compressed data size, which is needed to locate the next member.
Header structure
The 54-byte member header seems to have the following structure:
| Offset | Size (in file) | Size (decoded) | Description |
|---|---|---|---|
| 0 | 8 | 4 | DOS date, time |
| 8 | 8 | 4 | Compressed size |
| 16 | 8 | 4 | Original size |
| 24 | 4 | 2 | CRC of compressed data. The CRC algorithm seems to be the one named "CRC-16/IBM-3740" by the CRC RevEng catalogue (a slight variant of CRC-16/XMODEM). |
| 28 | 4 | 2 | CRC of uncompressed data |
| 32 | 2 | 1 | Compression method |
| 34 | 20 | Filename, NUL-padded. This 20-byte field might use as little as 12 bytes for the filename, with the remaining bytes having an undetermined purpose. | |
Compression methods
Method 1 is uncompressed. Method 2 is LZW, possibly the same as Zoo. Method 3 has been observed, but is unidentified.
FWIW, there is a "Knowledge Dynamics LZW COMPRESSOR" format that was used in some video games: [1], via [2]. However, it seems different from the LZW compression used in LIF.
Sample files
- dosdrvrs.zip → *.LIF
- FINDEMO1.ZIP → *.LIF
- ORIGINWM.ZIP → *.LIF
