module Compress::Zip

Overview

The Compress::Zip module contains readers and writers of the zip file format, described at PKWARE's site.

Reading zip files

Two types are provided to read from zip files:

• Compress::Zip::File: can read zip entries from a File or from an IO::Memory and provides random read access to its entries.
• Compress::Zip::Reader: can only read zip entries sequentially from any IO.

Compress::Zip::File is the preferred method to read zip files if you can provide a File, because it's a bit more flexible and provides more complete information for zip entries (such as comments).

When reading zip files, CRC32 checksum values are automatically verified when finishing reading an entry, and Compress::Zip::Error will be raised if the computed CRC32 checksum does not match.

Writer zip files

Use Compress::Zip::Writer, which writes zip entries sequentially to any IO.

NOTE only compression methods 0 (STORED) and 8 (DEFLATED) are supported. Additionally, ZIP64 is not yet supported.

Defined in:

compress/zip/checksum_reader.cr
compress/zip/checksum_writer.cr
compress/zip/zip.cr

Constant Summary

CENTRAL_DIRECTORY_HEADER_SIGNATURE = 33639248

END_OF_CENTRAL_DIRECTORY_HEADER_SIGNATURE = 101010256

VERSION = 20_u16