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Format

Hierarchical File System

Summary

Name
Hierarchical File System
Identifiers
PUID: fmt/1105
Format type
Aggregate
Description
Hierarchical File System (HFS) is a file system developed by Apple primarily for Mac OS. Within HFS a storage volume is divided into logical blocks of 512 bytes. The Hierarchical File System groups these logical blocks into allocation blocks, which can contain one or more logical blocks, depending on the total size of the volume.
File extensions
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Source
Artefactual Systems Inc / Artefactual Systems Inc
Developed by
Apple Computer, Inc.
Supported by
Apple Computer, Inc.

Internal signatures

HFS

Note
Offset 1024, magic 0x4244 {12}, first block of volume bitmap always 0x0003{6}, size (in bytes) of allocation blocks (4 byte multiple of 512 so byte 4 always 00, byte 3 has 'even' value)[!&01]00

Byte sequences

Min Frag Length
Absolute from BOF
Offset
1024
Max offset
None
Byte Sequence
4244{12}0003{6}[!&01]00
Endianness
None

Changelog

  • Added in V93

    Release date
    30 November 2017

    Hierarchical File System: Signature developed as a collaborative effort between The Open Preservation Foundation, The National Archives, Artefactual Systems, New York Public Libraries and University of California, Los Angeles.

    Hierarchical File System: Full entry added. Developed as a collaborative effort between The Open Preservation Foundation, The National Archives, Artefactual Systems, New York Public Libraries and University of California, Los Angeles. HFS was also requested by Preservica.