[thirdparty/man-pages.git] / man5 / filesystems.5

.\" Copyright 1996 Daniel Quinlan (Daniel.Quinlan@linux.org)
.\"
.\" %%%LICENSE_START(GPLv2+_DOC_FULL)
.\" This is free documentation; you can redistribute it and/or
.\" modify it under the terms of the GNU General Public License as
.\" published by the Free Software Foundation; either version 2 of
.\" the License, or (at your option) any later version.
.\"
.\" The GNU General Public License's references to "object code"
.\" and "executables" are to be interpreted as the output of any
.\" document formatting or typesetting system, including
.\" intermediate and printed output.
.\"
.\" This manual is distributed in the hope that it will be useful,
.\" but WITHOUT ANY WARRANTY; without even the implied warranty of
.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
.\" GNU General Public License for more details.
.\"
.\" You should have received a copy of the GNU General Public
.\" License along with this manual; if not, see
.\" <http://www.gnu.org/licenses/>.
.\" %%%LICENSE_END
.\"
.\" 2007-12-14 mtk Added Reiserfs, XFS, JFS.
.\"
.TH FILESYSTEMS 5 2018-04-30 "Linux" "Linux Programmer's Manual"
.nh
.SH NAME
filesystems \- Linux filesystem types: ext, ext2, ext3, ext4, hpfs, iso9660,
JFS, minix, msdos, ncpfs nfs, ntfs, proc, Reiserfs, smb, sysv, umsdos, vfat,
XFS, xiafs,
.SH DESCRIPTION
When, as is customary, the
.B proc
filesystem is mounted on
.IR /proc ,
you can find in the file
.I /proc/filesystems
which filesystems your kernel currently supports;
see
.BR proc (5)
for more details.
There is also a legacy
.BR sysfs (2)
system call (whose availability is controlled by the
.\" commit: 6af9f7bf3c399e0ab1eee048e13572c6d4e15fe9
.B CONFIG_SYSFS_SYSCALL
kernel build configuration option since Linux 3.15)
that enables enumeration of the currently available filesystem types
regardless of
.I /proc
availability and/or sanity.
.PP
If you need a currently unsupported filesystem, insert the corresponding
kernel module or recompile the kernel.
.PP
In order to use a filesystem, you have to
.I mount
it; see
.BR mount (2)
and
.BR mount (8).
.PP
iThe following list provides a
short description of the available or historically available
filesystems in the Linux kernel.
See the kernel documentation for a comprehensive
description of all options and limitations.
.TP 10
.B ext
is an elaborate extension of the
.B minix
filesystem.
It has been completely superseded by the second version
of the extended filesystem
.RB ( ext2 )
and has been removed from the kernel (in 2.1.21).
.TP
.B ext2
is the high performance disk filesystem used by Linux for fixed disks
as well as removable media.
The second extended filesystem was designed as an extension of the
extended filesystem
.RB ( ext ).
See
.BR ext2 (5).
.TP
.B ext3
is a journaling version of the
.B ext2
filesystem.
It is easy to
switch back and forth between
.B ext2
and
.BR ext3 .
See
.BR ext3 (5).
.TP
.B ext4
is a set of upgrades to
.B ext3
including substantial performance and
reliability enhancements,
plus large increases in volume, file, and directory size limits.
See
.BR ext4 (5).
.TP
.B hpfs
is the High Performance Filesystem, used in OS/2.
This filesystem is
read-only under Linux due to the lack of available documentation.
.TP
.B iso9660
is a CD-ROM filesystem type conforming to the ISO 9660 standard.
.RS
.TP
.B "High Sierra"
Linux supports High Sierra, the precursor to the ISO 9660 standard for
CD-ROM filesystems.
It is automatically recognized within the
.B iso9660
filesystem support under Linux.
.TP
.B "Rock Ridge"
Linux also supports the System Use Sharing Protocol records specified
by the Rock Ridge Interchange Protocol.
They are used to further describe the files in the
.B iso9660
filesystem to a UNIX host, and provide information such as long
filenames, UID/GID, POSIX permissions, and devices.
It is automatically recognized within the
.B iso9660
filesystem support under Linux.
.RE
.TP
.B JFS
is a journaling filesystem, developed by IBM,
that was integrated into Linux in kernel 2.4.24.
.TP
.B minix
is the filesystem used in the Minix operating system, the first to run
under Linux.
It has a number of shortcomings, including a 64\ MB partition size
limit, short filenames, and a single timestamp.
It remains useful for floppies and RAM disks.
.TP
.B msdos
is the filesystem used by DOS, Windows, and some OS/2 computers.
.B msdos
filenames can be no longer than 8 characters, followed by an
optional period and 3 character extension.
.TP
.B ncpfs
is a network filesystem that supports the NCP protocol, used by
Novell NetWare.
.IP
To use
.BR ncpfs ,
you need special programs, which can be found at
.UR ftp://linux01.gwdg.de\:/pub\:/ncpfs
.UE .
.TP
.B nfs
is the network filesystem used to access disks located on remote computers.
.TP
.B ntfs
replaces Microsoft Window's FAT filesystems (VFAT, FAT32).
It has reliability, performance, and space-utilization enhancements
plus features like ACLs, journaling, encryption, and so on.
.TP
.B proc
is a pseudo filesystem which is used as an interface to kernel data
structures rather than reading and interpreting
.IR /dev/kmem .
In particular, its files do not take disk space.
See
.BR proc (5).
.TP
.B Reiserfs
is a journaling filesystem, designed by Hans Reiser,
that was integrated into Linux in kernel 2.4.1.
.TP
.B smb
is a network filesystem that supports the SMB protocol, used by
Windows for Workgroups, Windows NT, and Lan Manager.
See
.UR https://www.samba.org\:/samba\:/smbfs/
.UE .
.TP
.B sysv
is an implementation of the SystemV/Coherent filesystem for Linux.
It implements all of Xenix FS, SystemV/386 FS, and Coherent FS.
.TP
.B umsdos
is an extended DOS filesystem used by Linux.
It adds capability for
long filenames, UID/GID, POSIX permissions, and special files
(devices, named pipes, etc.) under the DOS filesystem, without
sacrificing compatibility with DOS.
.TP
.B tmpfs
is a filesystem whose contents reside in virtual memory.
Since the files on such filesystems typically reside in RAM,
file access is extremely fast.
See
.BR tmpfs (5).
.TP
.B vfat
is an extended FAT filesystem used by Microsoft Windows95 and Windows NT.
.B vfat
adds the capability to use long filenames under the MSDOS filesystem.
.TP
.B XFS
is a journaling filesystem, developed by SGI,
that was integrated into Linux in kernel 2.4.20.
.TP
.B xiafs
was designed and implemented to be a stable, safe filesystem by
extending the Minix filesystem code.
It provides the basic most
requested features without undue complexity.
The
.B xiafs
filesystem is no longer actively developed or maintained.
It was removed from the kernel in 2.1.21.
.SH SEE ALSO
.BR fuse (4),
.BR btrfs (5),
.BR ext2 (5),
.BR ext3 (5),
.BR ext4 (5),
.BR nfs (5),
.BR proc (5),
.BR tmpfs (5),
.BR fsck (8),
.BR mkfs (8),
.BR mount (8)
Commit	Line	Data
	1	.\" Copyright 1996 Daniel Quinlan (Daniel.Quinlan@linux.org)
	2	.\"
	3	.\" %%%LICENSE_START(GPLv2+_DOC_FULL)
	4	.\" This is free documentation; you can redistribute it and/or
	5	.\" modify it under the terms of the GNU General Public License as
	6	.\" published by the Free Software Foundation; either version 2 of
	7	.\" the License, or (at your option) any later version.
	8	.\"
	9	.\" The GNU General Public License's references to "object code"
	10	.\" and "executables" are to be interpreted as the output of any
	11	.\" document formatting or typesetting system, including
	12	.\" intermediate and printed output.
	13	.\"
	14	.\" This manual is distributed in the hope that it will be useful,
	15	.\" but WITHOUT ANY WARRANTY; without even the implied warranty of
	16	.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	17	.\" GNU General Public License for more details.
	18	.\"
	19	.\" You should have received a copy of the GNU General Public
	20	.\" License along with this manual; if not, see
	21	.\" <http://www.gnu.org/licenses/>.
	22	.\" %%%LICENSE_END
	23	.\"
	24	.\" 2007-12-14 mtk Added Reiserfs, XFS, JFS.
	25	.\"
	26	.TH FILESYSTEMS 5 2018-04-30 "Linux" "Linux Programmer's Manual"
	27	.nh
	28	.SH NAME
	29	filesystems \- Linux filesystem types: ext, ext2, ext3, ext4, hpfs, iso9660,
	30	JFS, minix, msdos, ncpfs nfs, ntfs, proc, Reiserfs, smb, sysv, umsdos, vfat,
	31	XFS, xiafs,
	32	.SH DESCRIPTION
	33	When, as is customary, the
	34	.B proc
	35	filesystem is mounted on
	36	.IR /proc ,
	37	you can find in the file
	38	.I /proc/filesystems
	39	which filesystems your kernel currently supports;
	40	see
	41	.BR proc (5)
	42	for more details.
	43	There is also a legacy
	44	.BR sysfs (2)
	45	system call (whose availability is controlled by the
	46	.\" commit: 6af9f7bf3c399e0ab1eee048e13572c6d4e15fe9
	47	.B CONFIG_SYSFS_SYSCALL
	48	kernel build configuration option since Linux 3.15)
	49	that enables enumeration of the currently available filesystem types
	50	regardless of
	51	.I /proc
	52	availability and/or sanity.
	53	.PP
	54	If you need a currently unsupported filesystem, insert the corresponding
	55	kernel module or recompile the kernel.
	56	.PP
	57	In order to use a filesystem, you have to
	58	.I mount
	59	it; see
	60	.BR mount (2)
	61	and
	62	.BR mount (8).
	63	.PP
	64	iThe following list provides a
	65	short description of the available or historically available
	66	filesystems in the Linux kernel.
	67	See the kernel documentation for a comprehensive
	68	description of all options and limitations.
	69	.TP 10
	70	.B ext
	71	is an elaborate extension of the
	72	.B minix
	73	filesystem.
	74	It has been completely superseded by the second version
	75	of the extended filesystem
	76	.RB ( ext2 )
	77	and has been removed from the kernel (in 2.1.21).
	78	.TP
	79	.B ext2
	80	is the high performance disk filesystem used by Linux for fixed disks
	81	as well as removable media.
	82	The second extended filesystem was designed as an extension of the
	83	extended filesystem
	84	.RB ( ext ).
	85	See
	86	.BR ext2 (5).
	87	.TP
	88	.B ext3
	89	is a journaling version of the
	90	.B ext2
	91	filesystem.
	92	It is easy to
	93	switch back and forth between
	94	.B ext2
	95	and
	96	.BR ext3 .
	97	See
	98	.BR ext3 (5).
	99	.TP
	100	.B ext4
	101	is a set of upgrades to
	102	.B ext3
	103	including substantial performance and
	104	reliability enhancements,
	105	plus large increases in volume, file, and directory size limits.
	106	See
	107	.BR ext4 (5).
	108	.TP
	109	.B hpfs
	110	is the High Performance Filesystem, used in OS/2.
	111	This filesystem is
	112	read-only under Linux due to the lack of available documentation.
	113	.TP
	114	.B iso9660
	115	is a CD-ROM filesystem type conforming to the ISO 9660 standard.
	116	.RS
	117	.TP
	118	.B "High Sierra"
	119	Linux supports High Sierra, the precursor to the ISO 9660 standard for
	120	CD-ROM filesystems.
	121	It is automatically recognized within the
	122	.B iso9660
	123	filesystem support under Linux.
	124	.TP
	125	.B "Rock Ridge"
	126	Linux also supports the System Use Sharing Protocol records specified
	127	by the Rock Ridge Interchange Protocol.
	128	They are used to further describe the files in the
	129	.B iso9660
	130	filesystem to a UNIX host, and provide information such as long
	131	filenames, UID/GID, POSIX permissions, and devices.
	132	It is automatically recognized within the
	133	.B iso9660
	134	filesystem support under Linux.
	135	.RE
	136	.TP
	137	.B JFS
	138	is a journaling filesystem, developed by IBM,
	139	that was integrated into Linux in kernel 2.4.24.
	140	.TP
	141	.B minix
	142	is the filesystem used in the Minix operating system, the first to run
	143	under Linux.
	144	It has a number of shortcomings, including a 64\ MB partition size
	145	limit, short filenames, and a single timestamp.
	146	It remains useful for floppies and RAM disks.
	147	.TP
	148	.B msdos
	149	is the filesystem used by DOS, Windows, and some OS/2 computers.
	150	.B msdos
	151	filenames can be no longer than 8 characters, followed by an
	152	optional period and 3 character extension.
	153	.TP
	154	.B ncpfs
	155	is a network filesystem that supports the NCP protocol, used by
	156	Novell NetWare.
	157	.IP
	158	To use
	159	.BR ncpfs ,
	160	you need special programs, which can be found at
	161	.UR ftp://linux01.gwdg.de\:/pub\:/ncpfs
	162	.UE .
	163	.TP
	164	.B nfs
	165	is the network filesystem used to access disks located on remote computers.
	166	.TP
	167	.B ntfs
	168	replaces Microsoft Window's FAT filesystems (VFAT, FAT32).
	169	It has reliability, performance, and space-utilization enhancements
	170	plus features like ACLs, journaling, encryption, and so on.
	171	.TP
	172	.B proc
	173	is a pseudo filesystem which is used as an interface to kernel data
	174	structures rather than reading and interpreting
	175	.IR /dev/kmem .
	176	In particular, its files do not take disk space.
	177	See
	178	.BR proc (5).
	179	.TP
	180	.B Reiserfs
	181	is a journaling filesystem, designed by Hans Reiser,
	182	that was integrated into Linux in kernel 2.4.1.
	183	.TP
	184	.B smb
	185	is a network filesystem that supports the SMB protocol, used by
	186	Windows for Workgroups, Windows NT, and Lan Manager.
	187	See
	188	.UR https://www.samba.org\:/samba\:/smbfs/
	189	.UE .
	190	.TP
	191	.B sysv
	192	is an implementation of the SystemV/Coherent filesystem for Linux.
	193	It implements all of Xenix FS, SystemV/386 FS, and Coherent FS.
	194	.TP
	195	.B umsdos
	196	is an extended DOS filesystem used by Linux.
	197	It adds capability for
	198	long filenames, UID/GID, POSIX permissions, and special files
	199	(devices, named pipes, etc.) under the DOS filesystem, without
	200	sacrificing compatibility with DOS.
	201	.TP
	202	.B tmpfs
	203	is a filesystem whose contents reside in virtual memory.
	204	Since the files on such filesystems typically reside in RAM,
	205	file access is extremely fast.
	206	See
	207	.BR tmpfs (5).
	208	.TP
	209	.B vfat
	210	is an extended FAT filesystem used by Microsoft Windows95 and Windows NT.
	211	.B vfat
	212	adds the capability to use long filenames under the MSDOS filesystem.
	213	.TP
	214	.B XFS
	215	is a journaling filesystem, developed by SGI,
	216	that was integrated into Linux in kernel 2.4.20.
	217	.TP
	218	.B xiafs
	219	was designed and implemented to be a stable, safe filesystem by
	220	extending the Minix filesystem code.
	221	It provides the basic most
	222	requested features without undue complexity.
	223	The
	224	.B xiafs
	225	filesystem is no longer actively developed or maintained.
	226	It was removed from the kernel in 2.1.21.
	227	.SH SEE ALSO
	228	.BR fuse (4),
	229	.BR btrfs (5),
	230	.BR ext2 (5),
	231	.BR ext3 (5),
	232	.BR ext4 (5),
	233	.BR nfs (5),
	234	.BR proc (5),
	235	.BR tmpfs (5),
	236	.BR fsck (8),
	237	.BR mkfs (8),
	238	.BR mount (8)