IDEN Chunk

See more on Chunks in general.

This identifies this file, especially when part of a multi-file archive.

IDEN Chunk structure


The p (multi-part) & c, and y (payload specification) flags are all available.

The y flag is legal, as it may be able to compress the name information. However, the payload specification must use only built-in compression values, and may not use encryption or an extended payload specification.

Instance Number

The Instance Number must be 0. There is only one instance per archive file (in a multi-file archive, each portion file can have its own).

IDEN Chunk Payload

The Payload contains a record consisting of the following fields:


This is an lpstring containing the base name of the archive. It should match the base part of the original file name, but if the file is renamed this will preserve the archive’s name. This does not contain path information, the sequence number, or the extension.

Portion Number

This is a uintV containing the portion number of this file.

Portion Count

This is a uintV containing the number of portions in the archive. If this number is not known, the special value 0 may be used. However, the last portion should be positivily identified by having a Portion Count that matches the Portion Number.

Usage Notes


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