Editing Be File System (section)

{{short description|Native file system of the BeOS operating system}}
{{infobox filesystem
| name                    = BFS
| full_name               = Be File System
| developer               = [[Be Inc.]]
| introduction_os         = [[BeOS]] Advanced Access Preview Release<ref>{{cite web | url=http://www.zdnet.com/products/osuser/boj/hacker10.html  | title=BeOS Journal 10: A First Look at DR9 | author=Scot Hacker | date=1997-07-01 | work=ZDNet | access-date=2007-03-22 |archive-url = https://web.archive.org/web/19991002123347/http://www.zdnet.com/products/osuser/boj/hacker10.html |archive-date = 1999-10-02}}</ref>
| introduction_date       = {{Start date and age|1997|05|10}}
| partition_id            = Be_BFS ([[Apple Partition Map|Apple]])<br>[[Partition type#PID_EBh|0xEB]] ([[Master Boot Record|MBR]])<br/>{{mono|42465331-3BA3-10F1-802A-4861696B7521}} ([[GUID Partition Table|GPT]])
| directory_struct        = [[B+ tree]]<ref name="practical-book" />
| file_struct             = [[inode]]s
| bad_blocks_struct       = inodes
| max_filename_size       = 255 characters
| max_files_no            = Unlimited
| max_volume_size         = ~2 [[Exabyte|EB]] *
| max_file_size           = ~260 [[Gigabyte|GB]] *
| filename_character_set  = All [[UTF-8]] but "/"
| dates_recorded          = Access, Creation, Modified
| date_range              = Unknown
| date_resolution         = 1s
| forks_streams           = Yes
| attributes              = 
| file_system_permissions = Unix permissions, [[Access-control_list#POSIX_ACL|POSIX ACLs]]
| compression             = No
| encryption              = No
| OS                      = [[BeOS]], [[Magnussoft ZETA|ZETA]], [[Haiku (operating system)|Haiku]], [[SkyOS]], [[Syllable (operating system)|Syllable]], [[Linux]]
}}
The '''Be File System''' ('''BFS''') is the native [[file system]] for the [[BeOS]]. In the Linux kernel, it is referred to as "BeFS" to avoid confusion with [[Boot File System]].

BFS was developed by [[Dominic Giampaolo]] and [[Cyril Meurillon]] over a ten-month period, starting in September 1996,<ref name="practical-book">{{cite book | last=Giampaolo | first=Dominic | year=1999 | url=http://www.nobius.org/~dbg/practical-file-system-design.pdf | title=Practical File System Design with the Be File System | publisher=Morgan Kaufmann | isbn=1-55860-497-9 | format=PDF | access-date=2004-06-01 | archive-url=https://web.archive.org/web/20170213221835/http://www.nobius.org/~dbg/practical-file-system-design.pdf | archive-date=2017-02-13 | url-status=dead }}</ref> to provide BeOS with a modern [[64-bit]]-capable [[journaling file system]].<ref>{{cite web | url=https://www.theregister.co.uk/2002/03/29/windows_on_a_database_sliced/ | title=Windows on a database – sliced and diced by BeOS vets | author=Andrew Orlowski | date=2002-03-29 | publisher=The Register | access-date=2006-12-09| archive-url= https://web.archive.org/web/20061230040241/https://www.theregister.co.uk/2002/03/29/windows_on_a_database_sliced/| archive-date= 30 December 2006 | url-status= live}}</ref> It is [[case-sensitive]] and capable of being used on [[floppy disk]]s, [[hard disk]]s and read-only media such as [[CD-ROM]]s. However, its use on small removable media is not advised, as the file-system headers consume from 600 KB to 2 MB, rendering floppy disks virtually useless.

Like its predecessor, OFS (Old Be File System, written by [[Benoit Schillings]] - formerly BFS),<ref name="bortmaninterview">{{cite web | url=http://www.birdhouse.org/beos/bible/bos/int_schillings.html | title=Benoît Schillings, Software Engineer | author=Henry Bortman | work=The BeOS Bible | access-date=2006-09-10| archive-url= https://web.archive.org/web/20060927061917/http://www.birdhouse.org/beos/bible/bos/int_schillings.html| archive-date= 27 September 2006 | url-status= live}}</ref> it includes support for extended file attributes ([[Metadata (computing)|metadata]]), with indexing and querying characteristics to provide functionality similar to that of a [[relational database]].

Whilst intended as a 64-bit-capable file system, the size of some on-disk structures mean that the practical size limit is approximately 2 [[exabytes]]. Similarly the extent-based file allocation reduces the maximum practical file size to approximately 260 gigabytes at best and as little as a few blocks in a pathological worst case, depending on the degree of [[file system fragmentation|fragmentation]].{{citation needed|date=March 2021}}

Its design process, [[application programming interface]], and internal workings are, for the most part, documented in the book ''Practical File System Design with the Be File System''.<ref name="practical-book" />