Hierarchical File System (Apple)

This article is about the Apple file system used prior to Mac OS X 10.6. For the general concept, see Hierarchical file system. For the IBM file system with the same name, see Hierarchical File System (IBM MVS).
Not to be confused with Filesystem Hierarchy Standard.
HFS
Developer(s)Apple Computer
Full nameHierarchical File System
IntroducedSeptember 17, 1985; 39 years ago (1985-09-17) with System 2.1
Preceded byMFS
Succeeded byHFS Plus
Partition IDsApple_HFS (Apple Partition Map)
0xAF (MBR) HFS and HFS+
Structures
Directory contentsB-tree
File allocationBitmap
Bad blocksB-tree
Limits
Max volume size2 TB (2 × 10244 bytes)
Max file size2 GB (2 × 10243 bytes)
Max no. of files65535
Max filename length31 characters
Allowed filename
characters		All 8-bit values except :. Discouraged null and non-printing characters.
Features
Dates recordedCreation, modification, backup
Date rangeJanuary 1, 1904 – February 6, 2040
Date resolution1s
ForksOnly 2 (data and resource)
AttributesColor (3 bits, all other flags 1 bit), locked, custom icon, bundle, invisible, alias, system, stationery, inited, no INIT resources, shared, desktop
File system
permissions		AppleShare
Transparent
compression		Yes (third-party); Stacker, AutoDoubler, TimesTwo, Now Compress, StuffIt SpaceSaver, Alysis Software products (SuperDisk!, More Disk Space, The Alysis Disk Expander and eDisk), AutoSqueeze
Transparent
encryption		No
Other
Supported
operating systems		Classic Mac OS, macOS, GS/OS, Linux, Microsoft Windows (through MacDrive or Boot CampIFS drivers)[citation needed]

Hierarchical File System (HFS) is a proprietary file system developed by Apple Inc. for use in computer systems running Mac OS. Originally designed for use on floppy and hard disks, it can also be found on read-only media such as CD-ROMs. HFS is also referred to as Mac OS Standard (or HFS Standard), while its successor, HFS Plus, is also called Mac OS Extended (or HFS Extended).

With the introduction of Mac OS X 10.6, Apple dropped support for formatting or writing HFS disks and images, which remained supported as read-only volumes until macOS 10.15.[1] Starting with macOS 10.15, HFS disks can no longer be read.

  1. ^ Gagne, Ken (2009-08-31). "Losing legacy data to Snow Leopard". Computerworld. Retrieved 2009-09-07.