An outline proposal. Rev 2

[Dave Pawson]

Picking up on Bobs comments.

I've left in the binary/text format.
Rationale: If left unsaid, we could have an implementation that is compliant but
doesn't deal with one or the other.

If used 'package entity' and 'packaged entity', but boy do they
stick in the throat! any improvement in terms please?


Dave



2010-10-09T21:29:51Z
Outline requirements for a zip specification.
rev 1.0, Dave Pawson. 2010-10-19T13:12:33Z
rev 1.1, added update from Bob Jolliffe.


1. Provide a compressed archive format for general use. The container
shall be known as a package entity.

1.1. A compression algorithm shall be provided which is used
unconditionally and in perpetuity and without encumberance or payment
of any sort

1.2. A compression algorithm shall be provided which may be used
unconditionally and in perpetuity and without encumberance or payment
of any sort.

1.3 The goal should that the users of the standard may practice the
 algorithm without payment of any royalties.


2. The package entity shall hold one or more file.

2.1 It will be possible to extract one or more individual files from
the package.

2.2 Any file hierarchy present when the package is created shall be
duplicated on extraction if requested.

2.3 The package shall hold any combintation of  binary and/or text
files.

2.3.1 There shall be no difference between a file prior to being
archived and the corresponding file when extracted from the archive.

2.3.2 No change shall be made to any character encoding by compressing
and decompressing a file. I.e. an input file after decompression must
match its character encoding prior to compression.

3. A means of verification of an archive shall be provided.
    Deleted: retained for numbering only.

4. A means of listing the contents of an archive without extraction
shall be provided.

5. A package listing shall be created as a a plain text file within
the archive which lists all files within the archive excepting
itself. This may be used as a way of achieving requirement 4. This
file shall be known as the menifest.


5. A means of extracting the contents of an archive shall be provided
which meets the requirement of 2.3.1

5.1. A decompression algorithm shall be provided which is usable without
infringing any existent patent.

5.2. A decompression algorithm shall be provided which may be used
without payment of any sort.

Scope:

Zip as a packaging mechanism? DH
Not as a compression archive format.
? Not as a means of software deployment?

* How issues
OK for pkzip now, without special featuers.




Not understood:

zip/D for documents.

Plain text manifest


* Definitions needed:

The package entity: The item holding one or more packaged entities,
which may be files.

A packaged entity is an item contained within the package entity. It
may be a file.


Archive, archive format.

Stream (if used)





-- 
Dave Pawson
XSLT XSL-FO FAQ.
Docbook FAQ.
http://www.dpawson.co.uk