Cabinet (file format)

Design and Structure of CAB Files - CAB archives can contain up to 65,535 folders, each of which can contain up to 65,535 files. - Each folder is treated as a single compressed block, providing more efficient compression. - Every entry in a folder has to be a file; empty folders cannot be stored in CAB archives. - The structure of a CAB file includes folders and files. - Paths in CAB files can be handled differently depending on the software implementation. Implementations of CAB Files - Microsoft Windows supports creating and extracting CAB archives using various command-line utilities and tools. - Other software like WinZip, WinRAR, and 7-Zip also support CAB archives. - Linux systems have tools like cabextract and gcab for extracting and creating CAB archives. - A full list of file archivers that support CAB format can be found in the Comparison of file archivers. - Different tools have different capabilities, such as extracting only or both extracting and creating CAB archives. Uses of CAB Files - CAB format is used in various Microsoft installation technologies like Windows Installer and Setup API. - It is also used in self-extracting programs like IExpress. - CAB files can be embedded into other files like MSI and MSU files. - Windows uses the cabinet format to archive its Component-Based Servicing (CBS) log. - On Linux systems, CAB archives are used by fwupd for distributing firmware updates. Related Formats and Extensions - The .cab extension is also used by other installer programs for their proprietary archiving formats. - InstallShield, for example, uses zlib for compression but has incompatible headers with Microsoft CAB files. - Specialized utilities like Unshield can extract these proprietary formats. - Windows CE installer uses a variant of Microsoft CAB format with a specific magic number. - Microsoft Publisher has a Pack and Go feature that bundles documents into CAB files with a .PUZ extension. References and Resources - Microsoft provides a Cabinet Software Development Kit for working with CAB files. - There are various tools and utilities available for working with CAB archives, both from Microsoft and third-party sources. - The Microsoft Cabinet Format is documented in the Open Specifications Documentation. - The compression algorithms used in CAB files include DEFLATE, Quantum compression, LZX, and NULL. - References and resources for further information on CAB format and related topics.