View source for Extended file system

{{Use dmy dates|date=May 2023}}
{{short description|Linux file system}}
{{Expand language|topic=|langcode=de|otherarticle=extended filesystem|date=March 2023}}
{{Infobox file system
| name                    = ext
| full_name               = extended file system
| developer               = [[Rémy Card]]
| variants                = 
| introduction_date       = {{Start date and age|1992|04|df=yes}}
| discontinuation_date    = {{Start date and age|1997|01|14|df=yes}}<br />with Linux 2.1.21
| preceded_by             = [[MINIX file system]]
| succeeded_by            = [[ext2]]
| partition_id            = 
| directory_struct        = Table
| file_struct             = {{ubl
 | '''Free space''': Linked list<ref>{{Cite web |title=freelists.c - fs/ext/freelists.c - Linux source code (2.1.20)|url=https://elixir.bootlin.com/linux/2.1.20/source/fs/ext/freelists.c#L13 |access-date=2023-05-14 |website=Bootlin}}</ref>
 | '''Metadata''': Table
}}
| bad_blocks_struct       = Table
| min_volume_size         = 
| max_volume_size         = 2 GB<ref name="anatomyExt4" />
| max_file_size           = 
| max_files_no            = 
| max_filename_size       = 255 characters<ref name="linux096c">{{Cite web|title=ext_fs.h - include/linux/ext_fs.h - Linux source code (0.96c-patch2)|url=https://elixir.bootlin.com/linux/0.96c-patch2/source/include/linux/ext_fs.h|access-date=14 May 2023|website=Bootlin}}</ref>
| max_dirname_size        = 
| max_directory_depth     = 
| dates_recorded          = 
| date_range              = 
| date_resolution         = 
| forks_streams           = 
| attributes              = 
| file_system_permissions = Unix permissions
| compression             = 
| encryption              = No
| data_deduplication      = 
| OS                      = 
| bootable                = 
| filename_character_set  = 
| file_types              = 
| introduction_os         = [[Linux]] 0.96c
| file_size_granularity   = 
| copy_on_write           = No
| website                 = <!-- {{url|www.example.com}} -->
}}

The '''extended file system''', or '''ext''', was implemented in April 1992 as the first [[file system]] created specifically for the [[Linux]] kernel. Although ext is not a specific file system name, it has been succeeded by [[ext2]], [[ext3]], and [[ext4]]. It has [[metadata]] structure inspired by traditional [[Unix filesystem]] principles, and was designed by [[Rémy Card]] to overcome certain limitations of the [[MINIX file system]].<ref>{{Cite web|url=http://www.april.org/groupes/entretiens/remy_card.html|title=Rémy Card (Interview, April 1998)|date=19 April 1999|publisher=April Association|access-date=8 February 2012|archive-url=https://web.archive.org/web/20120204082557/http://www.april.org/groupes/entretiens/remy_card.html|archive-date=4 February 2012|language=fr|url-status=dead}}</ref><ref name="anatomyExt4">{{Cite web |last=Jones |first=M. Tim |date=17 February 2009 |title=Anatomy of ext4 |url=http://www.ibm.com/developerworks/linux/library/l-anatomy-ext4/ |url-status= |archive-url=https://web.archive.org/web/20150220020146/http://www.ibm.com/developerworks/linux/library/l-anatomy-ext4/ |archive-date=2015-02-20 |access-date=8 February 2012 |publisher=IBM Developer Works}}</ref> It was the first implementation that used the [[virtual file system]] (VFS), for which support was added in the Linux kernel in version 0.96c, and it could handle file systems up to 2 gigabytes (GB) in size.<ref name=anatomyExt4 />

ext was the first in the series of extended file systems. In 1993, it was superseded by both [[ext2]] and [[Xiafs]], which competed for a time, but ext2 won because of its long-term viability: ext2 remedied issues with ext, such as the immutability of [[inode]]s and [[Fragmentation (computing)|fragmentation]].<ref>{{Cite web| url = https://e2fsprogs.sourceforge.net/ext2intro.html | title = Design and Implementation of the Second Extended Filesystem | first1 = Rémy | last1 = Card | first2 = Theodore | last2 = Ts'o | first3 = Stephen | last3 = Tweedie | access-date = 8 February 2012 | archive-url = https://web.archive.org/web/20120204044824/http://e2fsprogs.sourceforge.net/ext2intro.html | archive-date = 4 February 2012 | url-status = dead }} First published in {{Cite book | url = https://books.google.com/books?id=vRfKYgEACAAJ | title = First Dutch International Symposium on Linux | isbn = 90-367-0385-9 | publisher = State University of Groningen | year = 1995}}</ref>

== Other extended file systems ==
There are other members in the extended file system family:
* [[ext2]], the second extended file system.
* [[ext3]], the third extended file system.
* [[ext4]], the fourth extended file system.

== See also ==
* [[List of file systems]]
* [[Comparison of file systems]]

== References ==
{{Reflist}}

{{File systems}}

{{DEFAULTSORT:Extended is Enough File System}}

[[Category:1992 software]]
[[Category:Disk file systems]]
[[Category:File systems supported by the Linux kernel]]

{{Linux-stub}}