TERSE

File Format
Name	TERSE
Ontology	Electronic File Formats Compression TERSE
Released	1984?

TERSE is a data compression format used on OS/2, and on IBM mainframes. It is still in regular use on IBM mainframes to this day.

More research is needed to understand the scope of what TERSE was used for, and how many versions of it there are.

It can at least be used for single-file compression, as is done by the Advantis software listed below. This file format does not appear to have a conventional filename extension – compressed files may keep their original name.

Identification

At least some TERSE-compressed files start with bytes 05 01 01 00.

Related formats

The ZIP format documentation (APPNOTE) lists two "TERSE" compression methods:

10 - PKWARE Data Compression Library Imploding (old IBM TERSE)
18 - File is compressed using IBM TERSE (new)

So, apparently, PKWARE DCL Implode is closely related to TERSE.

Software

• TERSE utility by Michael Nagy and Advantis
  • [1] → tersepc.zip - Collection of binaries for several platforms
  • terse.zip - OS/2 binaries
  • IBM Knowledge Center: Terse Utility
• TerseDecompress – open source (Apache2 licensed) Java program, written by IBM, to decompresses TERSE files for mainframe.

Links

• Wikipedia article