See more on Chunks in general.

Pre-Defined Chunks

Reserved Instances of Chunks defined in the ZIP2 specification are known to an implementation implicitly and are not included in an actual archive file. But besides their implicit knowledge, they are exactly like any other chunks.

So, the simplest way to give an implementation knowledge of these common chunks is to provide actual chunks defining them, along with the other implementation files. In other words, a ZIP2 file that contains all the common chunks is given, and it is implicitly included when decoding any normal ZIP2 archive.

This has an advantage of being able to update the pre-defined chunks in a fully implementation-independant manner, and also means that no implementor will have to incorperate these definitions directly into code.

Standard Chunks Files

Links to download the files will go here.

File Names

Rather than one big file, there will be several files, to simplify adding new pre-defined chunks when old ones never change. An implementation can simply load all the files it finds following this naming system from the designated location.

Details will go here.

File Format

The files follow the definition of ZIP2 files, except that they contain Instance Numbers that are normally prohibited. A META chunk will identify this file as being special. They include HASH chunks to easily test for accidental updating of these reserved definitions, and SIGN chunks for more definitive verification.


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