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Cabinet (or CAB) is an archive file format for Microsoft Windows that supports lossless data compression and embedded digital certificates used for maintaining archive integrity. Cabinet files have .cab filename extensions and are recognized by their first 4 bytes ''MSCF''. Cabinet files were known originally as Diamond files.The CAB file format may employ the following compression algorithms: * DEFLATE – invented by Phil Katz, the author of the ZIP file format * Quantum compression – licensed from David Stafford, the author of the Quantum archiver * LZX – invented by Jonathan Forbes and Tomi Poutanen, given to Microsoft when Forbes joined the company A CAB archive can reserve empty spaces in the archive as well as for each file in the archive, for some application-specific uses like digital signatures or arbitrary data. CAB format is used by a variety of Microsoft installation technologies including Windows Installer, Setup API, Device Installer and AdvPack (used by Internet Explorer to install ActiveX components). CAB files are also often associated with self-extracting programs like IExpress and DirectX where the executable program extracts the associated CAB file. CAB files are also sometimes embedded into other files. For example, MSI and MSU files (the latter are CAB files with just another filename extension) usually included one or more embedded CAB files. == File structure == A CAB archive can contain up to 65535 CAB-folders, (not to be confused with file system folders) each can contain up to 65535 files. Internally, each CAB-folder is treated as a single compressed block, which provides more efficient compression than individually compressing each file. Every entry in a CAB-folder has to be a file.〔https://msdn.microsoft.com/en-us/library/bb267310.aspx Microsoft Cabinet Format〕 Due to this structure, it is not possible to store empty folders in CAB archives. The following shows an example a CAB file structure, demonstrating the relationship between CAB-folders and files: |} How paths should be handled is not specified in the CAB file format, leaving it to the software implementation. * Some affix file paths to filenames only, as if all files in a CAB archive are in a single folder. IExpress works this way, as does Microsoft Windows Explorer, which can open CAB archives as a folder. * Some can store the paths, and upon extraction, create folders as necessary. CABARC.EXE and EXTRACT.EXE (tools from Microsoft Cabinet SDK ) as well as lcab and cabextract (third-party open-source tools) work this way.* EXPAND.EXE, only since version 6 (which is included from Windows Vista to above) can extract files to their paths. The previous versions don't do it.〔http://ss64.org/viewtopic.php?id=1816〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Cabinet (file format)」の詳細全文を読む スポンサード リンク
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