AVPACK

File Format
Name	AVPACK
Ontology	Electronic File Formats Compression Executable compression AVPACK
Released	≤1992

AVPACK is an executable compression utility for DOS, developed by Andrei Volkov. It compresses EXE files (to EXE), and COM files (to COM).

Some AVPACK-compressed files can be decompressed by AVPACK, using the -X option.

AVPACK can also decompress many files compressed by EXEPACK, LZEXE, or PKLITE.

Identification

Compressed COM files start with bytes eb 12, then ASCII "AVPACK".

Compressed EXE files have bytes eb 10, then ASCII "AVPACK", at the start of the code image segment (refer to MS-DOS_EXE#Special file positions)). This is usually at offset 64, or 32 if the "encrypt" option was used.

In each case, the "AVPACK" string is followed by two bytes giving the minor and major version numbers.

Software

AVPACK:

• AVPACK at old-dos.ru
• ANORMAL's DOSEXE collections → Executable Tools Pack → packers/avpack.*

Decompression:

• AVPACK with -X option
• For some multi-format utilities that might be able to decompress AVPACK-compressed files, see Executable compression#Decompression software.