Editing Universal Disk Format (section)

== Compatibility ==
{{update|section|date=November 2020|reason=For many operating systems, the information is a decade old and may or may not reflect the current situation accurately}}
Many [[DVD player]]s do not support any UDF revision other than version 1.02. Discs created with a newer revision may still work in these players if the ISO 9660 bridge format is used. Even if an [[operating system]] claims to be able to read UDF 1.50, it still may only support the ''plain'' build and not necessarily either the ''VAT'' or ''Spared'' UDF builds.

[[macOS|Mac OS X]] 10.4.5 claims to support Revision 1.50 (see ''man mount_udf''), yet it can only mount disks of the ''plain'' build properly and provides no virtualization support at all. It cannot mount UDF disks with VAT, as seen with the Sony Mavica issue.<ref>{{cite web |url=http://support.apple.com/kb/TA26938?viewlocale=en_US |title=Sony Mavica UDF Compatibility Issue |date=19 February 2012 |website=Apple |access-date=16 July 2014 |url-status=dead |archive-url=https://web.archive.org/web/20120426172237/http://support.apple.com/kb/TA26938?viewlocale=en_US |archive-date=April 26, 2012}}</ref><ref>{{cite web |url=http://freecode.com/projects/udfmediareader |title=Mac OS X UDF Compatibility Issues |author=<!--Staff writer(s); no by-line.--> |date=11 July 2012 |website=Free(code) |access-date=16 July 2014}}</ref> Releases before 10.4.11 mount disks with Sparing Table but does not read its files correctly. Version 10.4.11 fixes this problem.<ref>{{cite web |url=https://www.apple.com/downloads/macosx/apple/macosx_updates/macosx10411comboupdateintel.html |title=Intel Update |date=14 November 2007 |website=Apple |access-date=16 July 2014 |url-status=dead |archive-url=https://web.archive.org/web/20100328145428/http://www.apple.com/downloads/macosx/apple/macosx_updates/macosx10411comboupdateintel.html |archive-date=March 28, 2010}}</ref><ref>{{cite web |url=https://www.apple.com/downloads/macosx/apple/macosx_updates/macosx10411comboupdateppc.html |title=PowerPC Update |date=14 November 2007 |website=Apple |access-date=16 July 2014 |url-status=dead |archive-url=https://web.archive.org/web/20100531005641/http://www.apple.com/downloads/macosx/apple/macosx_updates/macosx10411comboupdateppc.html |archive-date=May 31, 2010}}</ref>

Similarly, [[Windows XP]] Service Pack 2 (SP2) cannot read DVD-RW discs that use the UDF 2.00 sparing tables as a defect management system.<ref name="CD-ROM Drive">{{cite web |url=http://support.microsoft.com/kb/321640/en-us |title=CD-ROM Drive May Not Be Able to Read a UDF-Formatted Disc in Windows XP |publisher=Microsoft Support |url-status=live |archive-url=https://web.archive.org/web/20141215062925/http://support.microsoft.com/kb/321640/en-us |archive-date= Dec 15, 2014 }}</ref> This problem occurs if the UDF defect management system creates a sparing table that spans more than one sector on the DVD-RW disc. Windows XP SP2 can recognize that a DVD is using UDF, but Windows Explorer displays the contents of a DVD as an empty folder. A hotfix is available for this<ref>{{cite web |url=http://support.microsoft.com/kb/899527 |title=Windows XP UDF hotfix |publisher=microsoft.com}}</ref> and is included in Service Pack 3.<ref name="CD-ROM Drive"/>

Due to the default UDF versions and options, a UDF partition formatted by Windows cannot be written under macOS. On the other hand, a partition formatted by macOS cannot be directly written by Windows, due to the requirement of a [[Master boot record|MBR]] partition table. In addition, Linux only supports writing to UDF 2.01. A script for Linux and macOS called {{code|format-udf}} handles these incompatibilities by using UDF 2.01 and adding a fake MBR;<ref>{{cite web |title=JElchison/format-udf: Bash script to format a block device (hard drive or Flash drive) in UDF |url=https://github.com/JElchison/format-udf |website=GitHub |date=27 June 2020 |quote=The output is a drive that can be used for reading/writing across multiple operating system families: Windows, macOS, and Linux. This script should be capable of running in macOS or in Linux.}}</ref> for Windows the best solution is using the command-line tool {{code|format /FS:UDF /R:2.01}}.

Tools for repairing UDF file systems and for modifying their properties have been made for some operating systems. On Windows, the [[chkdsk]] tool is able to repair UDF file systems (if not too damaged, like any file system). A similar tool for Linux, <code>udffsck</code>, was under development by Vojtech Vladyka as an extension of [[fsck]], and it was planned to be added to the ''udftools'' package. However, it was abandoned by its developer in 2018.<ref>[https://github.com/pali/udftools/pull/7 udffsck 1.00-beta by argorain · Pull Request #7 · pali/udftools · GitHub]</ref> 

A tool for toggling the write protection flag, <code>udftune</code>, was under development by Johannes Truschnigg in 2023 but could not be merged into the main ''udftools'' package because its maintainer Pali Rohár has reportedly lost access to his GitHub account.<ref name=pali-github>[https://github.com/pali/udftools/pull/63#issuecomment-1889687420 udftune: Add initial implementation by jtru · Pull Request #63 · pali/udftools · GitHub (comment 1889687420 on January 12, 2024)]</ref>

{| class="wikitable sortable"
|+ Table of operating systems
| colspan=10 | 
* Unless otherwise noted, read and write support means that only the plain UDF build is supported, but not the VAT and spared build.
* Support for "read" means that a UDF formatted disk can be mounted by the system. It enables the user to read files from the UDF volume using the same interface that is used to access files on other disks connected to the computer.
* Support for "write" means that, in addition to reading files from a mounted UDF volume, data such as files can be modified, added, or deleted.
|-
!
! colspan="5" | UDF revision (read + write)
! colspan="2" | Non-plain
!
|-
! Operating system
! 1.02
! 1.50
! 2.0x
! 2.50
! 2.60
! VAT
! Sparing tables
! Note
|-
| [[AIX (operating system)|AIX]] 5.2, 5.3, 6.1
|
| {{yes}}
| {{yes}}
| {{no}}
| {{no}}
|
|
| 1.5 is default<ref>{{cite web |url=http://publib.boulder.ibm.com/infocenter/aix/v6r1/index.jsp |title=Welcome to the AIX 6.1 Information Center |publisher=IBM |access-date=25 September 2010}}</ref>
|-
| [[AmigaOS]] 4.0
| {{yes}}
| {{yes}}
|
|
|
|
|
|
|-
| [[BeOS]]/[[magnussoft ZETA]]/[[Haiku (operating system)|Haiku]]
| {{yes}}
| {{yes}}
| {{yes}}
| {{yes}}
| {{yes}}
|
|
|
|-
| [[OS/2]] (including [[eComStation]] and [[ArcaOS]])
|
|
| {{yes}}
|
|
|
|
| Additional fee drivers on OS/2.
|-
| [[FreeBSD]] 5.0 and newer
| {{partial|read only}}
| {{partial|read only}}<ref>{{cite web |title=FreeBSD 5.0-RELEASE Release Notes |url=https://www.freebsd.org/releases/5.0R/relnotes-i386.html#AEN1150}}</ref>
| {{no}}
| {{no}}
| {{no}}
| {{no}}
| {{yes}}
|
|-
| [[Linux kernel]] 2.2
| {{no}}
| {{no}}
| {{no}}
| {{no}}
| {{no}}
| {{no}}
| {{no}}
|
|-
| [[Linux kernel]] 2.4
| {{yes}}
| {{yes}}
| {{yes}}{{efn|name="linux24"|Linux version 2.3.17–2.4.5 supports only UDF revision up to 2.00, Linux version 2.4.6 and newer supports also UDF revision 2.01.}}
| {{no}}
| {{no}}
| {{yes}}
| {{yes}}
|
|-
| [[Linux kernel]] 2.6.0–2.6.25
| {{yes}}
| {{yes}}
| {{yes}}
| {{no}}
| {{no}}
| {{yes}}
| {{yes}}
| Kernel versions prior to 2.6.10 supported fewer media types.
|-
| [[Linux kernel]] 2.6.26 and newer
| {{yes}}
| {{yes}}
| {{yes}}
| {{partial|read only}}<ref name="linuxsrc">{{cite web
    | title = Linux 3.13: fs/udf/udf_sb.h
    | url = https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/fs/udf/udf_sb.h?id=v3.13#n11
    | date = 2013-09-24
    | access-date = 2014-01-29}}</ref>
| {{partial|read only}}<ref name=udf260p/>{{rp|10}}
| {{yes}}
| {{yes}}
| Permission-related mounting options added in 2.6.30.<ref>{{cite web
    | title = Linux 2.6.30 Changelog
    | url = http://kernelnewbies.org/Linux_2_6_30
    | date = 2009-06-12
    | access-date = 2015-09-13}}</ref> Auto-detection of UDF file system on hard disk is supported since version 2.6.30. Auto-detection of UDF file system on disk images was fixed in 4.11.
|-
| [[Mac OS 8#Mac OS 8.1|Mac OS 8.1]]–[[Mac OS 8#Mac OS 8.5|8.5]]
| {{yes}}
| {{no}}
| {{no}}
| {{no}}
| {{no}}
| {{no}}
| {{no}}
| Some earlier versions of Mac OS, such as [[System 7|7.5, 7.6]], and 8.0 are also supported via third-party utilities, along with additional UDF version support for 8.1 and 8.5.{{efn|name="MacOSExtraUDF"|Read and (depending on which utility is used) write support for UDF versions 1.02, 1.50, 2.00, and 2.01 (support for 1.50 is not natively present in 8.1 or 8.5, and 2.00 onwards was not supported by the classic Mac OS at all) on optical disks available with third party utilities such as [[Adaptec]]'s UDF Volume Access or Software Architects' DVD-RAM Tune-Up utilities.}}
|-
| [[Mac OS 8#Mac OS 8.6|Mac OS 8.6]], [[Mac OS 9]]
| {{yes}}
| {{yes}}
| {{no}}
| {{no}}
| {{no}}
| {{no}}
| {{no}}
| Additional UDF version support via third-party utilities.{{efn|name="MacOSExtraUDF"}}
|-
| [[Mac OS X]] 10.0–10.3
| {{yes}}
| {{yes}}<ref name="macmount103">{{cite web |title=mount_udf manpage for Mac OS X 10.3 |url=http://www.manpagez.com/man/8/mount_udf/osx-10.3.php |quote=UDF 1.50 is supported. UDF 2.0 and later is not.}}</ref>
| {{no}}<ref name="macmount103" />
| {{no}}
| {{no}}
| {{no}}
| {{no}}
|
|-
| [[Mac OS X]] 10.4
| {{yes}}
| {{yes}}
| {{yes}}
| {{no}}{{efn|Support via third party utility [[Roxio Toast|Toast]] 9+ [http://www.roxio.com/enu/products/toast9/plugin/overview.html HD Plugin]}}<ref name="macrec" />
| {{no}}{{efn|Support via third party utility Toast 9+}}
| {{no}}
| {{yes}}{{efn|Since version 10.4.11}}
| Can create UDF 1.50 (plain build) volumes using the <code>drutil</code> utility.
|-
| Mac OS X 10.5 and newer
| {{yes}}
| {{yes}}
| {{yes}}
| {{yes}}<ref name="macmount105">{{cite web |title=mount_udf manpage for Mac OS X 10.5 |url=http://www.manpagez.com/man/8/mount_udf/osx-10.5.php |quote=Reading of all UDF revisions (1.02–2.60) on both block device (e.g. hard drives and USB drives) and most optical media is supported. Writing to block devices, DVD-RW and DVD+RW is supported with the following exceptions: (1) Cannot write Finder Info, Resource Fork, or other extended attributes in UDF volumes of revision 1.02 and 1.50; (2) Cannot write to mirrored metadata partition.}}</ref><ref name="macrec">{{cite web |title=Disc Recording Release Notes for OS X v10.5 |url=https://developer.apple.com/library/content/releasenotes/MusicAudio/RN-DiscRecording/index.html |quote=This release note describes changes to the Disc Recording frameworks from OS X version 10.4. The Disc Recording content creation engine now supports writing UDF 2.0 discs in addition to UDF 1.02 and 1.5.}}</ref>
| {{partial|read only}}<ref name="macmount105" /><ref name="mactech">{{cite web |title=Mac Technology Overview – Kernel and Device Drivers Layer |url=https://developer.apple.com/library/content/documentation/MacOSX/Conceptual/OSX_Technology_Overview/SystemTechnology/SystemTechnology.html |quote=OS X supports reading UDF revisions 1.02 through 2.60 on both block devices and most optical media, and it supports writing to block devices and to DVD-RW and DVD+RW media using UDF 2.00 through 2.50 (except for mirrored metadata partitions in 2.50).}}</ref>
| {{yes}}
| {{yes}}
| To create, use <code>newfs_udf</code> utility.
|-
| [[NetBSD]] 4.0
| {{partial|read only}}<ref>{{cite web |url=https://www.netbsd.org/releases/formal-4/NetBSD-4.0.html |title=Announcing NetBSD 4.0 |quote=Added UDF support for optical media and block devices, see mount_udf(8). Read-only for now.}}</ref>
| {{partial|read only}}
| {{partial|read only}}
| {{partial|read only}}
| {{partial|read only}}
| {{yes}}
| {{yes}}
| Reading multi-session VAT, spared and metapartition variants<br> from all CD, DVD and BD variants as well as HDD and Flash media.
|-
| [[NetBSD]] 5.0
| {{yes}}
| {{yes}}
| {{yes}}
| {{yes}}
| {{yes}}
| {{yes}}
| {{yes}}
| Write support for all builds and media including multi-session VAT.<ref>{{cite web |url=http://www.netbsd.org/releases/formal-5/NetBSD-5.0.html |title=NetBsd 5 release notes |publisher=NetBSD}}</ref> Create new with <code>newfs_udf</code>.<br>Limited writing on 2.50/2.60 (due to needing pre-allocated, fixed sized metadata partition).<ref>{{cite web |url=http://netbsd.gw.com/cgi-bin/man-cgi?mount_udf+8+NetBSD-5.0 |title=NetBSD System Manager's Manual |access-date=25 September 2010}}</ref>
|-
| [[NetWare]] 5.1
|
|
|
|
|
|
|
|
|-
| NetWare 6
|
|
|
|
|
|
|
|
|-
| [[OpenBSD]] 3.8–3.9
| {{partial|read only}}<ref>{{cite web |url=https://www.openbsd.org/38.html|title=OpenBSD 3.8}}</ref>
| {{no}}
| {{no}}
| {{no}}
| {{no}}
| {{no}}
| {{no}}
|
|-
| [[OpenBSD]] 4.0–4.6
| {{partial|read only}}
| {{partial|read only}}<ref name="openbsd40">{{cite web |url=https://www.openbsd.org/40.html |title=OpenBSD 4.0}}</ref>
| {{no}}
| {{no}}
| {{no}}
| {{yes}}<ref name="openbsd40" />
| {{no}}
|
|- 
| [[OpenBSD]] 4.7
| {{partial|read only}}
| {{partial|read only}}
| {{partial|read only}}
| {{partial|read only}}<ref name="openbsd47">{{cite web |url=http://www.openbsd.org/47.html |title=The OpenBSD 4.7 Release |publisher=OpenBSD |access-date=25 September 2010}}
</ref>
| {{partial|read only}}<ref name="openbsd47"/>
| {{yes}}
| {{yes}}
|
|- 
| [[Solaris (operating system)|Solaris]] 7 11/99+
| {{yes}}
| {{yes}}
|
|
|
|
|
|
|-
| Solaris 8/9/10
| {{yes}}
| {{yes}}
|
|
|
|
|
|
|-
| [[DOS]], [[FreeDOS]], [[Windows 3.11]], [[Windows 95]], [[Windows 95#Editions|Windows 95 OSR2+]] and other DOS based OS
| {{no}}<ref name="msfscc">{{cite web |url=https://msdn.microsoft.com/en-us/library/cc232128.aspx |title=[MS-FSCC]: File System Control Codes: 6 Appendix B: Product Behavior|date=27 April 2022 }} Windows UDF File System Support table</ref>
| {{no}}
| {{no}}
| {{no}}
| {{no}}
| {{no}}
| {{no}}
| No native support. Filesystems that have an [[ISO9660]] backward compatibility structure can be read.
|-
| [[Windows 98]], [[Windows Me]]
| {{partial|read only and only for CD/DVD optical disks}}<ref>{{cite book|author=Microsoft Corporation|title=Microsoft Windows 98 Resource Kit|date=January 1998|publisher=Microsoft Press|isbn=978-1-57231-644-7|page=[https://archive.org/details/isbn_9781572316447/page/442 442]|chapter=Chapter 10 – Disks and File Systems|url=https://archive.org/details/isbn_9781572316447/page/442|access-date=9 September 2017|quote=Windows 98 has a new read-only Universal Disk Format (UDF) system, which supports reading media formatted according to UDF specification 1.02.}}</ref><ref>{{cite book|author=Microsoft Corporation|title=Microsoft Windows 98 Resource Kit|date=January 1998|publisher=Microsoft Press|isbn=978-1-57231-644-7|page=[https://archive.org/details/isbn_9781572316447/page/1316 1316]|chapter=Chapter 28 – Windows 98 Architecture|url=https://archive.org/details/isbn_9781572316447/page/1316|access-date=9 September 2017|quote=The 32-bit, protected-mode UDF file system in Windows 98 is implemented according to Revision 1.02 of Universal Disk Format Specification by Optical Storage Technology Association (OSTA). It provides read-only access to UDF-formatted media, such as DVD discs. The UDF file system uses VCACHE and is dynamic, requiring no configuration or static allocation on the part of the user.}}</ref><ref name="nt5dll">{{cite web |url=https://www.microsoft.com/msj/1197/nt5dll.aspx|title=A Programmer's Perspective on New System DLL Features in Windows NT 5.0, Part I |author=Matt Pietrek|date=November 1997|publisher=Microsoft Systems Journal |access-date=9 September 2017 |quote=Windows NT 5.0 also adds UDF (Universal Disk Format). ... The UDF implementations shipping in both Windows 98 (UDF 1.02) and Windows NT 5.0 (UDF 1.50) are read-only.|author-link=Matt Pietrek }}</ref><ref name="msfscc" />
| {{no}}
| {{no}}
| {{no}}
| {{no}}
| {{no}}
| {{no}}
| Additional read/write support via third party utilities{{efn|name="win3rd"|Read and write support for other UDF versions on optical disks available with third party utilities such as [[Drive Letter Access|DLA]], [[InCD]] or Toshiba/Panasonic/Matsushita UDF 2.5 driver. Read and write support for removable disks and hard disks available with third party utilities such as SAI's WriteUDF!.}}
|-
| [[Windows 2000]]
| {{partial|read only}}<ref name="nt5dll" /><ref name="inside2000">{{cite book|last1=Russinovich|first1=M. E.|last2=Solomon|first2=D. A.|title=Inside Microsoft Windows 2000|chapter-url=https://archive.org/details/insidemicrosoftw0000solo|chapter-url-access=registration|edition=Third|year=2000|publisher=Microsoft Press|location=Redmond, Washington|isbn=978-0-7356-1021-7|chapter=Chapter 12 – File Systems|quote=The Windows 2000 UDF file system implementation is ISO 13346-compliant and supports UDF versions 1.02 and 1.5. ... the Windows 2000 UDF driver (Udfs.sys) provides read-only support.}}</ref><ref name="winint4">{{cite book|last1=Russinovich|first1=M. E.|last2=Solomon|first2=D. A.|title=Microsoft Windows Internals, Fourth Edition: Microsoft Windows Server 2003, Windows XP, and Windows 2000|url=https://books.google.com/books?id=I2vjPx-6qK0C|edition=Fourth|year=2005|publisher=Microsoft Press|location=Redmond, Washington|isbn=0-7356-1917-4|page=691|chapter=Chapter 12 – File Systems|quote=The UDF driver supports UDF versions 1.02, version 1.5 on Windows 2000, and versions 2.0 and 2.01 on Windows XP and Windows Server 2003. ... the Windows UDF driver (Udfs.sys) provides read-only support. Windows does not implement support for other UDF features, including named streams, access control lists, or extended attributes.}}</ref><ref name="locfswin">{{cite report|id=WinHEC 2004 Version|date=May 5, 2004|section-url=http://download.microsoft.com/download/5/b/5/5b5bec17-ea71-4653-9539-204a672f11cf/locfilesys.doc|title=Local File Systems for Windows|publisher=Microsoft Corporation|pages=6–8|chapter=2.3 About the UDF File System|chapter-format=doc}}</ref><ref name="msfscc" />
| {{partial|read only}}
| {{no}}
| {{no}}
| {{no}}
| {{no}}
| {{no}}
| Additional read/write support via third party utilities{{efn|name="win3rd"}}
|-
| [[Windows XP]]/[[Windows Server 2003|Server 2003]]
| {{partial|read only}}<ref name="winint4" /><ref name="locfswin" /><ref name="msfscc" />
| {{partial|read only}}
| {{partial|read only}}
| {{no}}
| {{no}}
| {{yes}}
| {{yes}}{{efn|Service Pack 3 required}}
| Additional read/write support via third party utilities{{efn|name="win3rd"}}
|-
| [[Windows Vista]]
| {{yes}}<ref name="winint5">{{cite book|last1=Russinovich|first1=M. E.|last2=Solomon|first2=D. A.|last3=Ionescu|first3=A.|title=Windows Internals, 5th Edition: Windows Vista and Windows Server 2008|edition=5th|year=2009|publisher=Microsoft Press|location=Redmond, Washington|isbn=978-0-7356-3796-2
|page=981|chapter=Chapter 12 – File Systems|url=https://books.google.com/books?id=VgjAQjsc6g8C|quote=The UDF driver supports UDF versions up to 2.60. The Windows UDF driver (Udfs.sys) provides read-write support ... when using UDF 2.50 and read-only support when using UDF 2.60. However, Windows does not implement support for certain UDF features such as named streams and access control lists.}}</ref><ref name="winint6">{{cite book |last1=Russinovich |first1=M. E.|last2=Solomon |first2=D. A. |last3=Ionescu 
|first3=A. |title=Windows Internals, Part 2, 6th Edition: Windows 7 and Windows Server 2008 R2|edition=6th |year=2012 |publisher=Microsoft Press |location=Redmond, Washington |isbn=978-0-7356-6587-3
|page=393 |chapter=Chapter 12 – File Systems |url=https://books.google.com/books?id=_Y2WiG6WfGkC|quote=The UDF driver supports UDF versions up to 2.60. The Windows UDF driver (Udfs.sys) provides read-write support ... when using UDF 2.50 and read-only support when using UDF 2.60. However, Windows does not implement support for certain UDF features such as named streams and access control lists.}}</ref><ref name="locfswin" /><ref name="msfscc" />
| {{yes}}
| {{yes}}
| {{yes}}
| {{partial|read only}}<ref name="winint5" /><ref name="winint6" /><ref name="locfswin" /><ref name="msfscc" />
| {{yes}}
| {{yes}}
| Referred to by Microsoft as [[Live File System]]. Requires fake MBR partition on non-optical devices.
|-
| [[Windows 7]] and newer
| {{yes}}<ref name="msfscc" />
| {{yes}}
| {{yes}}
| {{yes}}
| {{yes}}
| {{yes}}
| {{yes}}
| 
|-
! Operating system
! 1.02
! 1.50
! 2.0x
! 2.50
! 2.60
! VAT
! Sparing tables
! Note
|-
!
! colspan="5" | UDF revision (read + write)
! colspan="2" | Non-plain
!
|}