About: Hierarchical File System   Sponge Permalink

An Entity of Type : owl:Thing, within Data Space : 134.155.108.49:8890 associated with source dataset(s)

The second Macintosh file system.

AttributesValues
rdfs:label
  • Hierarchical File System
rdfs:comment
  • The second Macintosh file system.
  • The Macintosh Heirarchical File System (HFS) was introduced by Apple in September 1985 to replace the Macintosh File System with a more robust format that provided support for disks of arbitrary sizes and layouts -- notably, it supported Apple's new HD20 hard disk drives (featuring 20 Mb of storage) and 800Kb double-sided disks instead of just the single-sided 400Kb floppy disks supported by MFS.
sameAs
dcterms:subject
abstract
  • The second Macintosh file system.
  • The Macintosh Heirarchical File System (HFS) was introduced by Apple in September 1985 to replace the Macintosh File System with a more robust format that provided support for disks of arbitrary sizes and layouts -- notably, it supported Apple's new HD20 hard disk drives (featuring 20 Mb of storage) and 800Kb double-sided disks instead of just the single-sided 400Kb floppy disks supported by MFS. Unlike the flat file structure used in MFS (MFS stored the directory listings in a table in the Desktop file), HFS contained an internal catalog file based on B-trees. Data in HFS was stored using 32-bit integers instead of 16-bit integers, providing maximum values of 4096x1024^2 instead of 65536. This impacted things such as maximum file size, which rose from 64Kb to 4Gb. Unfortunately, the one place 16-bit integers were still used was in the Desktop directory file, which limited the maximum number of files on each logical disk to 65536. HFS was the primary file system format used on Apple computers until HFS Plus was released eleven years later in 1996, finally adding 32-bit support for block addresses and the mapping table, and switching from Mac OS Roman to Unicode for character representation. HFS contained no transaction journal, so mild data corruption due to interrupted cached writes to disk would require a complete rebuild of the B-Tree, often resulting in the loss of files and file data.
Alternative Linked Data Views: ODE     Raw Data in: CXML | CSV | RDF ( N-Triples N3/Turtle JSON XML ) | OData ( Atom JSON ) | Microdata ( JSON HTML) | JSON-LD    About   
This material is Open Knowledge   W3C Semantic Web Technology [RDF Data] Valid XHTML + RDFa
OpenLink Virtuoso version 07.20.3217, on Linux (x86_64-pc-linux-gnu), Standard Edition
Data on this page belongs to its respective rights holders.
Virtuoso Faceted Browser Copyright © 2009-2012 OpenLink Software