بعض الفوائد من هذا الجدول هو معرفة الطول المسموح بكتابته لأسم الملف في أي نظام ملفات على أي نظام تشغيل ، ومعرفة أي الحروف والرموز المسموح بها والتي يمكن كتابتها لأي ملف أو مجلد على أي نظام تشغيل ، ومعرفة أكبر حجم ممكن لأي ملف ، ومعرفة إمكانيات عمل تقسيمات للقرص الصلب أو أي مخزنات بأكبر حجم مسموح به (Partition Size)، معرفة أكبر طول للمسار لأي ملف أو مجلد كمثال المسار في ويندوز لفيل إكسبلورر File Explorer يكون كالتالي (C:\Users\Default\AppData\Roaming\Microsoft\Internet Explorer\Quick Launch) وهذا الطول له سماحيات أيضا في نظم الملفات المختلفة، الخ .
البيانات الوصفية metadata هي بيانات تقنية (تكنولوجية) مهمة نفيد في نواحي كثيرة مثل السماحيات Permissions لأي ملف أو مجلد ، لأعطاء معلومات عن آخر وقت تم فيه قراءة أو تغير للملف (أو المجلد) وما فيه ، وآخر وقت تم فيه عملية أرشفة للملف ، وهل نظام الملفات لديه القدرة على تصحيح الخطأ (ECC) الخ .
هذا الجدول يوضح بيانات مهمة أيضا مثل هل يستطيع نظام الملفات أن يقوم بعمل وصلات الاختصارات Symbolic links ، وقدرة عمل وصلات صلبة Hard Links وهل لنظام الملفات القدرة على عمل صحائف journaling وهي مفيدة في نظام التشغيل (مثال الذاكرة الإفتراضية في ويندوز Virtual memory وفي لينكس هي المبدل Swap وكلاهما يساعد نظام التشغيل على زيادة قدرات التعامل مع البرامج الكثيرة والمفيدة في حالات الذاكرة RAM القليلة) إلخ .
^آي بي إم introduced JFS with the initial release of آي بي إم إيه آي إكس Version 3.1 in 1990. This file system now called JFS1. The new JFS, on which the Linux port was based, was first shipped in أو إس/2 Warp Server for e-Business in 1999. The same sourcebase was also used for release JFS2 on AIX 5L.
^ميكروسوفت first introduced FAT32 in ويندوز 95 OSR2 (OEM Service Release 2) and then later in ويندوز 98. NT-based Windows did not have any support for FAT32 up to Windows NT4; Windows 2000 was the first NT-based Windows OS that received the ability to work with it.
^ ابجدهFor filesystems that have variable allocation unit (block/cluster) sizes, a range of size are given, indicating the maximum volume sizes for the minimum and the maximum possible allocation unit sizes of the filesystem (e.g. 512 بايت and 128 كيبيبايت for FAT — which is the cluster size range allowed by the on-disk data structures, although some Installable File System drivers and نظام تشغيلs do not support cluster sizes larger than 32 كيبيبايت).
^ ابجدهوزحطDepends on whether the FAT12, FAT16, and FAT32 implementation has support for LFNs. Where it does not, as in أو إس/2، إم إس-دوس، ويندوز 95، ويندوز 98 in DOS-only mode and the Linux "msdos" driver, file names are limited to 8.3 format of 8-bit characters (space padded in both the basename and extension parts) and may not contain NUL (end-of-directory marker) or character 5 (replacement for character 229 which itself is used as deleted-file marker). Short names also do not normally contain lowercase letters. Also note that a few special names (CON, NUL, LPT1) should be avoided, as some operating systems (notably DOS and windows) effectively reserve them.
^ ابجدهوزحطييايبيجيديهيويزيحيطككاكبكجكدكهكوكزكحكطللالبلجIn these filesystems the directory entries named "." and ".." have special status. Directory entries with these names are not prohibited, and indeed exist as normal directory entries in the on-disk data structures. However, they are mandatory directory entries, with mandatory values, that are automatically created in each directory when it is created; and directories without them are considered corrupt.
^ ابجدهوزحطييايبيجيديهيويزيحيطككاكبكجكدكهكوكزكحكطللالبلجلدلهلوThe on-disk structures have no inherent limit. Particular Installable File System drivers and نظام تشغيلs may impose limits of their own, however. MS-DOS does not support full pathnames longer than 260 بايت for FAT12 and FAT16. Windows NT does not support full pathnames longer than 32,767 بايت for NTFS. Linux has a pathname limit of 4,096.
^The actual maximum was 8,847,360 بايت ، with 7 singly-indirect blocks and 1 doubly-indirect block; PWB/UNIX 1.0's variant had 8 singly-indirect blocks, making the maximum 524,288 بايت or half a مبيبايت.
^The actual maximum was 1,082,201,088 بايت ، with 10 direct blocks, 1 singly-indirect block, 1 doubly-indirect block, and 1 triply-indirect block. The 4.0توزيعة برمجيات بيركلي and 4.1توزيعة برمجيات بيركلي versions, and the System V version, used 1,024-byte blocks rather than 512-byte blocks, making the maximum 4,311,812,608 بايت or approximately 4 جيبي بايت.
^While FAT32 تقسيم القرصs this large work fine once created, some software won't allow creation of FAT32 partitions larger than 32 جيبي بايت. This includes, notoriously, the ويندوز إكس بي installation program and the Disk Management console in Windows 2000, XP, 2003 and Vista. Use FDISK from a ويندوز ميلينيوم Emergency Boot Disk to avoid.[4]
^The "." and ".." directory entries in HPFS that are seen by applications programs are a partial fiction created by the Installable File System drivers. The on-disk data structure for a directory does not contain entries by those names, but instead contains a special "start" entry. Whilst on-disk directory entries by those names are not physically prohibited, they cannot be created in normal operation, and a directory containing such entries is corrupt.
^This is the limit of the on-disk structures. The HPFS Installable File System driver for أو إس/2 uses the top 5 bits of the volume sector number for its own use, limiting the volume size that it can handle to 64 جيبي بايت.
^ ابThis is the limit of the on-disk structures. The NTFS driver for ويندوز إن تي limits the volume size that it can handle to 256 تيبي بايت and the file size to 16 تيبي بايت respectively.
^The Mac OS provides two sets of functions to retrieve file names from an HFS Plus volume, one of them returning the full Unicode names, the other shortened names fitting in the older 31 byte limit to accommodate older applications.
^HFS Plus mandates support for an تسلسل الهروب to allow arbitrary Unicode. Users of older software might see the escape sequences instead of the desired characters.
^ ابDepends on kernel version and arch. For 2.4 kernels the max is 2 TiB. For 32-bit 2.6 kernels it is 16 TiB. For 64-bit 2.6 kernels it is 8 EiB.
^ReiserFS has a theoretical maximum file size of 1 اكسبي بايت, but "page cache limits this to 8 Ti on architectures with 32 bit int"[11]
^Note that the filename can be much longer إكس إف إس
^ ابXFS has a limitation under Linux 2.4 of 64 تيبي بايت file size, but Linux 2.4 only supports a maximum block size of 2 تيبي بايت. This limitation is not present under آيركس.
^ ابQFS allows files to exceed the size of disk when used with its integrated HSM, as only part of the file need reside on disk at any one time.
^Varies wildly according to block size and fragmentation of block allocation groups.
^ ابNSS allows files to have multiple names, in separate namespaces.
^Some namespaces had lower name length limits. "LONG" had an 80-byte limit, "NWFS" 80 بايت ، "NFS" 40 بايت and "DOS" imposed اسم ملف 8.3.
^Maximum combined filename/filetype length is 236 بايت ; each component has an individual maximum length of 255 بايت .
^Maximum pathname length is 4,096 بايت ، but quoted limits on individual components add up to 1,664 بايت .
^This restriction might be lifted in newer versions.
^ ابMaximum file size on a VMFS volume depends on the block size for that VMFS volume. The figures here are obtained by using the maximum block size.
^Some FAT implementations, such as in Linux, show file modification timestamp (mtime) in the metadata change timestamp (ctime) field. This timestamp is however, not updated on file metadata change.
^Particular Installable File System drivers and نظام تشغيلs may not support extended attributes on FAT12 and FAT16. The OS/2 and Windows NT filesystem drivers for FAT12 and FAT16 support extended attributes (using a "EA DATA. SF" pseudo-file to reserve the clusters allocated to them). Other filesystem drivers for other operating systems do not.
^The f-node contains a field for a user identifier. This is not used except by أو إس/2, however.
^NTFS قائمة التحكم بالوصولs can express any access policy possible using simple POSIX file permissions (and far more), but use of a POSIX-like interface is not supported without an add-on such as Services for UNIX or سيج وين.
^ ابجدAccess-control lists and MAC labels are layered on top of extended attributes.
^Some operating systems implemented extended attributes as a layer over UFS1 with a parallel backing file (e.g., FreeBSD 4.x).
^ ابجدهوزحطييايبSome Installable File System drivers and نظام تشغيلs may not support extended attributes, access control lists or security labels on these filesystems. Linux kernels prior to 2.6.x may either be missing support for these altogether or require a باتش.
^ ابجدهوThe local time, timezone/توقيت عالمي منسق offset, and date are derived from the time settings of the reference/single timesync source in the NDS tree.
^ ابNovell calls this feature "multiple data streams". Published specifications say that NWFS allows for 16 attributes and 10 data streams, and NSS allows for unlimited quantities of both.
^ ابSome file and directory metadata is stored on the NetWare server irrespective of whether Directory Services is installed or not, like date/time of creation, file size, purge status, etc; and some file and directory metadata is stored in NDS/eDirectory, like file/object permissions, ownership, etc.
^Record Management Services (RMS) attributes include record type and size, among many others.
^File permission in 9P are a variation of the traditional Unix permissions with some minor changes, eg. the suid bit is replaced by a new 'exclusive access' bit.
^MAC/Sensitivity labels in the file system are not out of the question as a future compatible change but aren't part of any available version of ZFS.
^Solaris "extended attributes" are really full-blown alternate data streams, in both the Solaris UFS and ZFS.
^System V Release 4, and some other يونكس systems, retrofitted symbolic links to their versions of the نظام يونكس السابع file system, although the original version didn't support them.
^Context based symlinks were supported in GFS, GFS2 only supports standard symlinks since the bind mount feature of the Linux VFS has made context based symlinks obsolete
^As of Windows Vista, NTFS fully supports soft links.[18] NTFS 3.0 (Windows 2000) and higher can create junctions, which allow entire directories (but not individual files) to be mapped to elsewhere in the directory tree of the same partition (file system). These are implemented through reparse points, which allow the normal process of filename resolution to be extended in a flexible manner.
^ ابNTFS stores everything, even the file data, as meta-data, so its log is closer to block journaling.
^While NTFS itself supports case sensitivity, the Win32 environment subsystem cannot create files whose names differ only by case for compatibility reasons. When a file is opened for writing, if there is any existing file whose name is a case-insensitive match for the new file, the existing file is truncated and opened for writing instead of a new file with a different name being created. Other subsystems like e. g. Services for Unix, that operate directly above the kernel and not on top of Win32 can have case-sensitivity.
^NTFS does not internally support snapshots, but in conjunction with the Volume Shadow Copy Service can maintain persistent block differential volume snapshots.
^Metadata-only journaling was introduced in the Mac OS 10.2.2 HFS Plus driver; journaling is enabled by default on Mac OS 10.3 and later.
^Although often believed to be case sensitive, HFS Plus normally is not. The typical default installation is case-preserving only. From Mac OS 10.3 on the command newfs_hfs -s will create a case-sensitive new file system.[19] HFS Plus version 5 optionally supports case-sensitivity. However, since case-sensitivity is fundamentally different from case-insensitivity, a new signature was required so existing HFS Plus utilities would not see case-sensitivity as a file system error that needed to be corrected. Since the new signature is 'HX', it is often believed this is a new filesystem instead of a simply an upgraded version of HFS Plus.[20][21]
^Mac OS Tiger (10.4) and late versions of Panther (10.3) provide file change logging (it's a feature of the file system software, not of the volume format, actually).[22]
^HFS+ does not actually encrypt files: to implement FileVault, OS X creates an HFS+ filesystem in a sparse, encrypted disk image that is automatically mounted over the home directory when the user logs in.
^Particular Installable File System drivers and نظام تشغيلs may not support case sensitivity for JFS. OS/2 does not, and Linux has a mount option for disabling case sensitivity.
^ ابجدCase-sensitivity/Preservation depends on client. Windows, DOS, and OS/2 clients don't see/keep case differences, whereas clients accessing via NFS or AFP may.
^ ابThe file change logs, last entry change timestamps, and other filesystem metadata, are all part of the extensive suite of auditing capabilities built into NDS/eDirectory called NSure Audit.[24]
^VxFS provides an optional feature called "Storage Checkpoints" which allows for advanced file system snapshots.
^ ابZFS is a transactional filesystem using copy-on-write semantics, guaranteeing an always-consistent on-disk state without the use of a traditional journal. However, it does also implement an intent log to provide better performance when synchronous writes are requested.
^ ابVariable block size refers to systems which support different block sizes on a per-file basis. (This is similar to extents but a slightly different implementational choice.) The current implementation in UFS2 is read-only.
^ ابجدOther block:fragment size ratios supported; 8:1 is typical and recommended by most implementations.
^إكس تي 2, a set of باتش providing block-based ضغط بيانات for ext2, has been available since 1997, but has never been merged into the mainline Linux kernel.
^ ابجFragments were planned, but never actually implemented on ext2 and ext3.
^ ابTail packing is technically a special case of block suballocation where the suballocation unit size is always 1 byte.
^Each possible size (in sectors) of file tail has a corresponding suballocation block chain in which all the tails of that size are stored. The overhead of managing suballocation block chains is usually less than the amount of block overhead saved by being able to increase the block size but the process is less efficient if there is not much free disk space.
^See dinode structure on page 355 (FILESYS(5)) of "Unix Programmers Manual"(PDF) (ط. Seventh). Murray Hill, New Jersey: Bell Telephone Laboratories. يناير 1979. مؤرشف من الأصل(PDF) في 2016-04-29. اطلع عليه بتاريخ 2016-02-21.
^ اب"FAQ". Ext2 Installable File System For Windows. مؤرشف من الأصل في 2018-10-15. (Provides kernel level read/write access to Ext2 and Ext3 volumes in Windows NT4, 2000, XP and Vista.)