Editing File-system permissions (section)

==Examples==
File system permissions have been implemented many ways. Some notable examples are described here.<!--ordered somewhat by popularity, but with the classic Mac OS mentioned before macOS to provide some context-->

[[NTFS]] which is in many versions of [[microsoft windows|Windows]] including [[Windows 11|the current]], uses ACL technology to provide permission-based access control; considered powerful yet complex.<ref>{{cite web |url=https://technet.microsoft.com/en-us/library/bb727008.aspx |title=File and Folder Permissions |date=9 December 2009 |publisher=Microsoft}}</ref>

[[Linux]] file systems such as [[ext2]], [[ext3]], [[ext4]], [[Btrfs]] support both POSIX permissions and POSIX.1e ACLs. There is experimental support for NFSv4 ACLs for ext3<ref>{{cite web |url=http://www.suse.de/~agruen/nfs4acl/ |title=Native NFSv4 ACLs on Linux |access-date=May 4, 2010 |url-status=dead |archive-url=https://web.archive.org/web/20081012054117/http://www.suse.de/~agruen/nfs4acl/ |archive-date=October 12, 2008 }}</ref> and ext4 filesystems.

[[FreeBSD]] supports POSIX.1e ACLs on UFS, and NFSv4 ACLs on UFS and ZFS.<ref>{{cite web |url=http://wiki.freebsd.org/NFSv4_ACLs |title=NFSv4_ACLs – FreeBSD Wiki }}</ref><ref>{{cite web |url=http://www.freenas.org/images/resources/freenas9.1.1/freenas9.1.1_guide.pdf |title=FreeNAS 9.1.1 Users Guide |date=2013 |url-status=dead |archive-url=https://web.archive.org/web/20150924015431/http://www.freenas.org/images/resources/freenas9.1.1/freenas9.1.1_guide.pdf |archive-date=September 24, 2015}}</ref>

[[Hierarchical File System (Apple)|HFS]], and its successor [[HFS Plus|HFS+]], as implemented in the [[Classic Mac OS]] operating systems, do not support permissions.

[[macOS]] supports POSIX-compliant permissions, and supports them in both HFS+ and [[APFS]]. Beginning with version 10.4 ("Tiger"), it also supports the use of NFSv4 ACLs in addition to POSIX-compliant permissions. The ''Apple Mac OS X Server version 10.4+ File Services Administration Manual'' recommends using only traditional Unix permissions if possible. macOS also still supports the Classic Mac OS's "Protected"/"Locked" attribute as the "user immutable" flag in [[Chattr#In BSD-like systems (chflags)|the 4.4BSD flags field]].<ref>{{cite web |url=https://www.cyberciti.biz/faq/apple-osx-write-protecting-file-folders-bash-command/ |title=Apple OS X: Write Protect File From Command Line |first=Vivek |last=Gite |date=June 3, 2010}}</ref>

[[File Allocation Table]] (original version) has a per-file read-only attribute that applies to all users.

[[OpenVMS]] defines four access functions: read, write, execute and delete and user selections: system, owner, group, and world where world includes group which in turn includes owner and system selects system users. This design is similar to that of Unix with notable extensions: additional function: delete and additional user selection: system.<ref>{{cite web |url=http://h71000.www7.hp.com/doc/731final/6489/6489pro_025.html#int_prot_code |title=OpenVMS documentation |access-date=June 6, 2009 |archive-url=https://web.archive.org/web/20120305181412/http://h71000.www7.hp.com/doc/731final/6489/6489pro_025.html#int_prot_code |archive-date=March 5, 2012 |url-status=dead}}</ref> ACLs are supported in VMS 4.0 and later.<ref>{{cite web |url=https://www.math-cs.gordon.edu/courses/cs322/slides/file_systems/fs90.html |title=File Systems: Protection |work=CS322 Lecture Slides}}</ref>

[[Solaris (operating system)|Solaris]] ACL support depends on the filesystem being used; older [[Unix File System|UFS]] filesystem supports POSIX.1e ACLs, while [[ZFS]] supports only NFSv4 ACLs.<ref>{{cite web |url=http://docs.oracle.com/cd/E19253-01/819-5461/819-5461.pdf |title=Oracle Solaris ZFS Administration Guide |date=Sep 2010}}</ref>

[[IBM z/OS]] implements file security using RACF (Resource Access Control Facility)<ref>{{cite web |url=http://publib.boulder.ibm.com/infocenter/zos/v1r12/index.jsp?topic=%2Fcom.ibm.zos.r12.e0ze100%2Fracf.htm |archive-url=https://archive.today/20130629123357/http://publib.boulder.ibm.com/infocenter/zos/v1r12/index.jsp?topic=/com.ibm.zos.r12.e0ze100/racf.htm |url-status=dead |archive-date=June 29, 2013 |title=IBM Knowledge Center }}</ref>

[[AmigaDOS|The AmigaOS Filesystem, AmigaDOS]] supports a permissions system relatively advanced for a single-user OS. In AmigaOS 1.x, files had Archive, Read, Write, Execute and Delete (collectively known as ARWED) permissions/flags. In AmigaOS 2.x and higher, additional Hold, Script, and Pure permissions/flags were added.

[[OpenHarmony]] operating system alongside its client side ecosystem in Oniro OS and [[HarmonyOS]] with [[HarmonyOS NEXT]] versions and also [[Linux|Linux-based]] [[EulerOS|openEuler]] server OS natively uses its Harmony Distributed File System (HMDFS) that supports access token manager ([[role-based access control]]) and Core File Kit API capability-based with granular permission management with exception to openEuler.<ref>{{cite web |title=HarmonyOS Distributed File System Development Guide |url=https://livinginharmony.substack.com/p/harmonyos-distributed-file-system |website=Substack |date=13 March 2024 |publisher=LivingInHarmony Blog |access-date=13 March 2024}}</ref>{{failed verification|date=July 2024}}