HFS (file system)

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HFS
Manufacturer Apple computer
Full name Hierarchical File System
Initial release September 17, 1985 ( system 2.1 )
Partition identifier Apple_HFS( APM )
0xAF( MBR )
Technical implementation
Directories B * tree
Files B * tree
Defect block list B * tree
Maximum values
Size of a file 2 GB
Number of all files 65,535
Length of the file name 31 characters
File system size 2 TB
Allowed characters in the file name All 8-bit characters except colon ":". NULL and non-printable characters are not recommended
properties
Dates of a file Creation, modification, backup
Date range January 1, 1904 - February 6, 2040
Forks Only 2 (data and resource)
File attributes Color (3 bits, all other 1 bit), locked, custom icon, bundle, invisible, alias, system, stationery, inited, no INIT resources, shared, desktop
File rights management AppleShare
Transparent compression supported (by other manufacturers), stacker
Transparent encryption No
Supporting operating systems Mac OS , Mac OS X , BeOS , Linux

The Hierarchical File System ( Engl. Hierarchical File System) is a file system that of Apple computer with the Macintosh System Software (from 1996 in Mac OS was developed renamed). In 1985, it replaced the Macintosh File System (MFS) introduced only a year earlier with System Software 0.5 (System 2.1 ). In Mac OS X , it was called the Mac OS Standard .

Other operating systems such as BeOS and Linux also have read and write support for HFS. Although it was originally designed for floppy disks and hard drives , it can also be found on read-only media such as CD-ROMs . HFS is a proprietary format. However, since it is very well documented, most modern operating systems have solutions for accessing HFS-formatted media.

It was superseded in 1998 with the release of Mac OS 8.1 by HFS + , which in Mac OS X is called Mac OS Extended .

history

HFS was introduced as the new file system for Apple Macintosh computers in January 1986 . The acronym HFS stands for H ierarchical F ile S ystem , hierarchical file system , so a file system with subdirectories - in contrast to the previously used Macintosh File System (MFS), which as a " flat file system supports" no subdirectories and used by the earliest Macs has been.

In 1998, Apple introduced HFS + to address inefficient allocation of space in HFS and add other improvements. However, since the introduction of Mac OS X, it is no longer possible to boot from an HFS volume because the maximum number of files (65,536) on an HFS volume is insufficient. HFS is still fully supported by versions of Mac OS X Leopard (10.5, 2007). Write support has been removed in Mac OS X Snow Leopard (10.6, 2009). In macOS Sierra (10.12, 2016) HFS is no longer included.

more details

HFS supports file names up to a length of 31 characters, Mac-specific metadata and dual-fork files. With the dual fork process, the actual file (data fork) is supplemented by additional information ( resource fork ), e.g. B. Icons . Both parts of the file can be read and written - each separately -. The "data fork" is mostly used sequentially, while the "resource fork" is used like a database. The partition is invisible to the end user, but accessible to the programmer.

See also

Web links

Individual evidence

  1. a b File-System Performance Guidelines - Overview of OS X File Systems. In: Apple Developer Documentation Archive. Apple, accessed March 18, 2020 .
  2. Macintosh HFS Filesystem for Linux ( Memento of the original from December 19, 2013 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. (English) - in the Linux Cross Reference Documentation (last accessed on April 9, 2018) @1@ 2Template: Webachiv / IABot / lxr.linux.no
  3. 60+ new features in macOS Sierra (English) - Christian Zibreg in the iDownloadBlog , on September 20, 2016; requires JavaScript to display the actual content