Editing HFS Plus (section)

{{short description|Journaling file system developed by Apple}}
{{Infobox filesystem
| name = HFS+
| full_name = Hierarchical File System Plus
| developer = [[Apple Inc.]]
| introduction_os = [[Mac OS 8#Mac OS 8.1|Mac&nbsp;OS&nbsp;8.1]]
| introduction_date = {{Start date and age|1998|01|19}}
| preceded_by = [[Hierarchical File System (Apple)|HFS]]
| succeeded_by = [[Apple File System|APFS]]
| partition_id = <code>Apple_HFS</code> ([[Apple Partition Map]])<hr /><code>0xAF</code> ([[Master boot record|MBR]]) HFS and HFS+<hr /><code>Apple_HFSX</code> ([[Apple Partition Map]]) when HFSX <br /><code>48465300-0000-11AA-<br />AA11-00306543ECAC</code> ([[GUID Partition Table|GPT]])
| directory_struct = [[B-tree]]
| file_struct = [[Bit array|Bitmap]]
| bad_blocks_struct = [[B-tree]]
| max_files_no = 4,294,967,295 (2<sup>32</sup> − 1)
| max_file_size = 8&nbsp;[[exabyte|EB]]<ref name="tn1150" />
| max_filename_size = 255 characters (255 UTF-16 encoding units, normalized to Apple-modified variant of Unicode Normalization Format D)
| max_volume_size = 8&nbsp;[[exabyte]]<ref>{{cite web |url=http://support.apple.com/kb/HT2422 |title=OS X: Mac OS Extended format (HFS Plus) volume and file limits |publisher=Support.apple.com |date=2008-07-29 |access-date=2010-07-05 |url-status=live |archive-url=https://web.archive.org/web/20100730000158/http://support.apple.com/kb/ht2422 |archive-date=2010-07-30 }}</ref>
| filename_character_set = [[Unicode]], any character, including [[ASCII#ASCII control characters|NUL]]. OS APIs may limit some characters for legacy reasons
| dates_recorded = access, attributes modified, backed up, contents modified, created
| date_range = {{date|1904-01-01|MDY}} – {{date|2040-02-06|MDY}}<ref>{{cite web|url=https://developer.apple.com/library/archive/technotes/tn/tn1150.html#HFSPlusDates|title=HFS Plus Dates|work=HFS Plus Volume Format|id=Technical Note TN1150|date=March 5, 2004|publisher=[[Apple Inc.]]}}</ref>
| date_resolution = 1&nbsp;s
| forks_streams = Yes
| attributes = Color (3 bits, all other flags 1 bit), locked, custom icon, bundle, invisible, alias, system, stationery, inited, no INIT resources, shared, desktop
| file_system_permissions = Unix permissions, [[NFSv4]] [[Access control list|ACL]]s ([[Mac OS X Tiger|Mac OS X v10.4]] onward)
| compression = Partial (decmpfs, on [[Mac OS X Snow Leopard|Mac OS X 10.6]] and higher)<ref>{{cite web|url=http://hints.macworld.com/article.php?story=20090902223042255|title=10.6: Compress files with HFS+ compression – Mac OS X Hints|url-status=live|archive-url=https://web.archive.org/web/20120401035614/http://hints.macworld.com/article.php?story=20090902223042255|archive-date=2012-04-01}}</ref>
| encryption = Yes (on [[Mac OS X Lion|Mac OS X 10.7]] and up). Per-[[home directory]] encryption is available with [[Advanced Encryption Standard|AES]]{{Clarify|reason=AES is a block cipher. Not an applicable method of disk encryption.|date=March 2012}} using HFS+-formatted [[Apple Disk Image|.dmg]] volumes on OS X versions prior to 10.7 but later than [[Mac OS X Panther|Mac OS X 10.3]]
| OS = [[Mac OS 8#Mac OS 8.1|Mac OS 8.1]], [[Mac OS 9]], [[macOS]], [[iOS]], [[tvOS]], [[watchOS]], [[Darwin (operating system)|Darwin]], [[Linux]], [[Microsoft Windows]] (through [[Boot Camp (software)|Boot Camp]] [[Installable File System|IFS]] drivers)
|variants=
|data_deduplication=
}}

'''HFS Plus''' or '''HFS+''' (also known as '''Mac OS Extended''' or '''HFS Extended'''<ref>{{cite web | url=https://developer.apple.com/documentation/coreservices/kuccollatetypehfsextended | title=kUCCollateTypeHFSExtended - Apple Developer Documentation | publisher=developer.apple.com | accessdate=2025-01-16 }}</ref>) is a [[journaling file system]] developed by [[Apple Inc.]]  It replaced the [[Hierarchical File System (Apple)|Hierarchical File System]] (HFS) as the primary file system of Apple computers with the 1998 release of [[Mac OS 8|Mac OS 8.1]].  HFS+ continued as the primary [[Mac OS X]] file system until it was itself replaced with the [[Apple File System]] (APFS), released with [[macOS High Sierra]] in 2017. HFS+ is also one of the formats supported by the [[iPod]] digital music player. 

Compared to its predecessor [[Hierarchical File System (Apple)|HFS]], also called ''Mac OS Standard'' or ''HFS Standard,'' HFS Plus supports much larger files (block addresses are 32-bit length instead of 16-bit) and using [[Unicode]] (instead of [[Mac OS Roman]] or any of several other character sets) for naming items. Like HFS, HFS Plus uses [[B-tree]]s to store most volume [[metadata]], but unlike most file systems that support [[hard link]]s, HFS Plus supports hard links to directories. HFS Plus permits filenames up to 255 characters in length, and [[Fork (file system)|n-forked file]]s similar to [[NTFS]], though until 2005 almost no system software took advantage of forks other than the [[Resource fork|data fork]] and [[resource fork]]. HFS Plus also uses a full 32-bit allocation mapping table rather than HFS's 16 bits, improving the use of space on large disks.