In
computing, the fdisk
command-line
A command-line interpreter or command-line processor uses a command-line interface (CLI) to receive commands from a user in the form of lines of text. This provides a means of setting parameters for the environment, invoking executables and pro ...
utility provides
disk-partitioning functions, preparatory to defining
file systems.
fdisk
features in the
DOS,
DR FlexOS,
IBM OS/2, and
Microsoft Windows operating systems, and in certain ports of
FreeBSD,
NetBSD,
OpenBSD,
DragonFly BSD and
macOS for compatibility reasons. In versions of the
Windows NT operating-system line from
Windows 2000
Windows 2000 is a major release of the Windows NT operating system developed by Microsoft and oriented towards businesses. It was the direct successor to Windows NT 4.0, and was released to manufacturing on December 15, 1999, and was officially ...
onwards, is replaced by a more advanced tool called
diskpart
In computing, diskpart is a command-line disk partitioning utility included in Windows 2000 and later Microsoft operating systems, replacing its predecessor, fdisk. The command is also available in ReactOS.
Overview
The diskpart is a utility ...
. Similar utilities exist for
Unix-like systems, for example,
BSD disklabel
In BSD-derived computer operating systems (including NetBSD, OpenBSD, FreeBSD and DragonFly BSD) and in related operating systems such as SunOS, a disklabel is a record stored on a data storage device such as a hard disk that contains informati ...
.
Implementations
IBM PC DOS
IBM introduced ,
Fixed Disk
A hard disk drive (HDD), hard disk, hard drive, or fixed disk is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage with one or more rigid rapidly rotating platters coated with magneti ...
Setup Program version 1.00, with the March 1983 release of the
IBM PC/XT, the first PC to store data on a
hard disk
A hard disk drive (HDD), hard disk, hard drive, or fixed disk is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage with one or more rigid rapidly rotating platters coated with magneti ...
, and the
IBM Personal Computer DOS version 2.0. Version 1 could be used to create one
FAT12 DOS partition, delete it, change the
active partition, or display partition data. writes the
master boot record, which supported up to four partitions. The other three were intended for other operating systems such as
CP/M-86
CP/M-86 was a version of the CP/M operating system that Digital Research (DR) made for the Intel 8086 and Intel 8088. The system commands are the same as in CP/M-80. Executable files used the relocatable .CMD file format. Digital Research also ...
and
Xenix
Xenix is a discontinued version of the Unix operating system for various microcomputer platforms, licensed by Microsoft from AT&T Corporation in the late 1970s. The Santa Cruz Operation (SCO) later acquired exclusive rights to the software, and e ...
, which were expected to have their own partitioning utilities as did not support them.
In August 1984, PC DOS 3.0 added
FAT16 partitions to support larger hard disks more efficiently.
In April 1987, PC DOS/fdisk 3.30 added support for
extended partitions, which could hold up to 23 "logical drives" or
volumes
Volume is a measure of occupied three-dimensional space. It is often quantified numerically using SI derived units (such as the cubic metre and litre) or by various imperial or US customary units (such as the gallon, quart, cubic inch). The de ...
.
IBM PC DOS 7.10 contained and utilities.
Microsoft DOS and Windows
The command is available in
MS-DOS
MS-DOS ( ; acronym for Microsoft Disk Operating System, also known as Microsoft DOS) is an operating system for x86-based personal computers mostly developed by Microsoft. Collectively, MS-DOS, its rebranding as IBM PC DOS, and a few oper ...
versions 3.2 and later.
MS-DOS versions 2.0 through 3.10 included OEM specific partitioning tools, which may or may-not be called .
Support for
FAT16B
File Allocation Table (FAT) is a file system developed for personal computers. Originally developed in 1977 for use on floppy disks, it was adapted for use on hard disks and other devices. It is often supported for compatibility reasons by c ...
was added with Compaq MS-DOS 3.31, and later became available with
MS-DOS
MS-DOS ( ; acronym for Microsoft Disk Operating System, also known as Microsoft DOS) is an operating system for x86-based personal computers mostly developed by Microsoft. Collectively, MS-DOS, its rebranding as IBM PC DOS, and a few oper ...
/PC DOS 4.0.
Most
DOS programs, including the program that came with the original
Windows 95
Windows 95 is a consumer-oriented operating system developed by Microsoft as part of its Windows 9x family of operating systems. The first operating system in the 9x family, it is the successor to Windows 3.1x, and was released to manufacturi ...
, are only capable of creating
FAT
In nutrition, biology, and chemistry, fat usually means any ester of fatty acids, or a mixture of such compounds, most commonly those that occur in living beings or in food.
The term often refers specifically to triglycerides (triple est ...
partitions of types FAT12, FAT16 and FAT16B.
A derivative of the MS-DOS was provided with Windows 95,
Windows 98
Windows 98 is a consumer-oriented operating system developed by Microsoft as part of its Windows 9x family of Microsoft Windows operating systems. The second operating system in the 9x line, it is the successor to Windows 95, and was released t ...
, and later
Windows ME
Windows Millennium Edition, or Windows Me (marketed with the pronunciation of the pronoun "me"), is an operating system developed by Microsoft as part of its Windows 9x family of Microsoft Windows operating systems. It is the successor to Win ...
. Only those versions shipping with Windows 95B or later are able to manipulate
FAT32 partitions.
Windows 2000
Windows 2000 is a major release of the Windows NT operating system developed by Microsoft and oriented towards businesses. It was the direct successor to Windows NT 4.0, and was released to manufacturing on December 15, 1999, and was officially ...
and later do not use , they have the
Logical Disk Manager feature, as well as .
Unlike the programs for other operating systems, the programs for DOS and
Windows 9x
Windows 9x is a generic term referring to a series of Microsoft Windows computer operating systems produced from 1995 to 2000, which were based on the Windows 95 kernel and its underlying foundation of MS-DOS, both of which were updated in subs ...
/Me not only alter data in the
partition table
Disk partitioning or disk slicing is the creation of one or more regions on secondary storage, so that each region can be managed separately. These regions are called partitions. It is typically the first step of preparing a newly installed disk, ...
, but will also overwrite many sectors of data in the partition itself. (However, to create an
extended partition any
partition editor
A disk editor is a computer program that allows its user to read, edit, and write raw data (at character or hexadecimal, byte-levels) on disk drives (e.g., hard disks, USB flash disks or removable media such as a floppy disks); as such, the ...
must put
extended boot records before each
logical drive
In computer data storage, a volume or logical drive is a single accessible storage area with a single file system, typically (though not necessarily) resident on a single partition of a hard disk. Although a volume might be different from a physi ...
on the disk.) Users must be sure the correct disk/partition has been chosen before using a DOS/Windows for partitioning. The switch is undocumented but well known for repairing the
master boot record.
The supplied with Windows 95 does not report the correct size of a hard disk that is larger than 64 GB. An updated is available from Microsoft that corrects this. Microsoft named the replacement "263044usa8" and is Version 4.72.2811.0. Signature May 23, 2000. The original Windows 98 program size is smaller than the updated one.
cannot create partitions larger than 512 GB, despite that the maximal FAT32 partition size is 2 TB. This limitation applies to all versions of supplied with Windows 95 OSR 2.1, Windows 98 and Windows ME.
IBM OS/2
OS/2 shipped with two partition table managers up until version 4.0. These were the
text mode ''fdisk'' and the
GUI-based ''fdiskpm''. The two have identical functionality, and can manipulate both FAT partitions and the more advanced
HPFS partitions.
OS/2 versions 4.5 and higher (including
eComStation and
ArcaOS
ArcaOS is an operating system based on OS/2, developed and marketed by Arca Noae, LLC under license from IBM. It was codenamed Blue Lion during its development. It builds on OS/2 Warp 4.52 by adding support for new hardware, fixing defects and l ...
) can use the
JFS filesystem as well as FAT and HPFS, and replace with the
Logical Volume Manager (LVM).
DR/Novell DOS and FlexOS
DR DOS 6.0[DR DOS 6.0 User Guide Optimisation and Configuration Tips](_blank)
/ref> and FlexOS include an implementation of the command.
ROM-DOS
Datalight
Datalight was a privately held software company specializing in power failsafe and high performance software for preserving data integrity in embedded systems. The company was founded in 1983 by Roy Sherrill, and is headquartered in Bothell, Was ...
ROM-DOS
Datalight was a privately held software company specializing in power failsafe and high performance software for preserving data integrity in embedded systems. The company was founded in 1983 by Roy Sherrill, and is headquartered in Bothell, Was ...
includes an implementation. ROM-DOS was introduced in 1989 as an MS-DOS compatible operating system designed for embedded systems. ROM-DOS 7.1 added support for FAT32 and long file names.
FreeDOS
The implementation of in FreeDOS is free software.
The FreeDOS version was developed by Brian E. Reifsnyder and is licensed under the GNU GPLv2
The GNU General Public License (GNU GPL or simply GPL) is a series of widely used free software licenses that guarantee end users the four freedoms to run, study, share, and modify the software. The license was the first copyleft for general us ...
.
PTS-DOS
Paragon Technology Systems PTS-DOS 2000 Pro includes an implementation.
Mach and 386BSD
for Mach Operating System was written by Robert Baron. It was ported to 386BSD
386BSD (also known as "Jolix") is a discontinued Unix operating system based on the Berkeley Software Distribution (BSD). It was released in 1992 and ran on PC-compatible computer systems based on the 32-bit Intel 80386 microprocessor. 386BSD in ...
by Julian Elischer, and the implementation is being used by FreeBSD,[
*] NetBSD and DragonFly BSD,[
*] all as of 2019, as well as the early versions of OpenBSD between 1995 and 1997 before OpenBSD 2.2.
Tobias Weingartner re-wrote in 1997 before OpenBSD 2.2,[
*] which has subsequently been forked by Apple Computer, Inc in 2002, and is still used as the basis for on macOS as of 2019.
For native partitions, BSD systems traditionally use BSD disklabel
In BSD-derived computer operating systems (including NetBSD, OpenBSD, FreeBSD and DragonFly BSD) and in related operating systems such as SunOS, a disklabel is a record stored on a data storage device such as a hard disk that contains informati ...
, and partitioning is supported only on certain architectures (for compatibility reasons) and only in addition to the BSD disklabel (which is mandatory).
Linux
In Linux, fdisk
is a part of a standard package distributed by the Linux Kernel organization, util-linux
is a standard package distributed by the Linux Kernel Organization for use as part of the Linux operating system. A fork, (with meaning "next generation"), was created when development stalled, but has been renamed back to , and is the offic ...
. The original program was written by Andries E. Brouwer and A. V. Le Blanc and was later rewritten by Karel Zak and Davidlohr Bueso when they forked the util-linux
package in 2006.
See also
* List of disk partitioning software
* format (command)
* cfdisk
* GUID Partition Table
The GUID Partition Table (GPT) is a standard for the layout of partition tables of a physical computer storage device, such as a hard disk drive or solid-state drive, using universally unique identifiers, which are also known as globally uniqu ...
References
Further reading
*
*
*
External links
Linux Partition HOWTO. Partitioning with fdisk
fdisk from utils-linux-ng
blkid - command-line utility to locate/print block device attributes
.
FreeBSD System Manager's Manual, FDISK(8)
{{Windows commands
External DOS commands
OS/2 commands
Unix file system-related software
Windows administration
Disk partitioning software