OS/2 PACK archive

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(Format details)
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== Format details ==
 
== Format details ==
The compression scheme is possibly the same [[LZW]]-based format used by [[LoadDskF/SaveDskF]].
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=== Compression scheme ===
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The compression is a kind of [[LZW]] with 12-bit codes. Code 0 marks the end of data; codes 1-256 are literals; 257-4095 are dynamic. If the code table is full, the least-recently-used leaf code is reused.
 +
 
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This is the same compression used by [[LoadDskF/SaveDskF]].
 +
 
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=== Other format details ===
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The format apparently supports OS/2 extended attributes, compressed independently following the compressed file data.
  
 
== Identification ==
 
== Identification ==

Revision as of 17:59, 17 March 2024

File Format
Name OS/2 PACK archive
Ontology
Extension(s) .??_, .??@, others

OS/2 PACK archive is a compressed archive format used for software installation on OS/2.

This article covers the format with signature bytes a5 96 fe ff. For signature a5 96 fd ff, see OS/2 PACK2 archive.

PACK format is generally associated with the OS/2 PACK.EXE and UNPACK.EXE utilities.

Contents

Format details

Compression scheme

The compression is a kind of LZW with 12-bit codes. Code 0 marks the end of data; codes 1-256 are literals; 257-4095 are dynamic. If the code table is full, the least-recently-used leaf code is reused.

This is the same compression used by LoadDskF/SaveDskF.

Other format details

The format apparently supports OS/2 extended attributes, compressed independently following the compressed file data.

Identification

Files start with bytes a5 96 fe ff.

Software

OS/2 software:

Sample files

Personal tools
Namespaces

Variants
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