XPACK
XPACK (often written XPAck in later versions) is a multi-function compression utility for DOS, probably best known for its executable compression. It was developed by JauMing Tseng. Some versions were distributed as freeware, others as shareware.
This article covers the executable compression and single-file compression formats, and the software in general. Some native XPACK formats have their own articles:
Contents |
Disambiguation
- XPACK is not the same as X-pack for Executable (XE.EXE).
- DOS XPACK is not the same as the XPA/Xpa32/XPAGUI/"XPACK-archiver for Win32" programs by the same author. More research is needed to understand the relationships of these things.
- There is an unrelated collection of DOS utilities also named XPACK: XPACK.ZIP
Format details
XPACK does executable compression of .EXE and .COM files.
It supports single-file compression of arbitrary data files, and has a TSR utility to do transparent decompression. Such files are presumably expected to retain their original filename.
It has an .XPA compressed archive format.
It has an .XDI compressed floppy disk image format.
Identification
At least some compressed EXE files have "xpac" at offset 28.
Compressed data files apparently start with bytes 0xcd 0x20 'j' 'm'.
Software
- Various versions of XPACK at old-dos.ru
- XPACK v1.34
- XPACK v1.44
- XPACK v1.49
- XPACK v1.60
- XPACK v1.64
- XPACK v1.67.m
- XPAck v1.67.r
Ed. note: Unable to get v1.64 or earlier to run in DOSBox -- it just says "XPACK is corrupt".
