![]() The MS-DOS FORMAT command | |
Written in | MS-DOS: x86 assembly language FreeDOS: C |
---|---|
Operating system | RT-11, 86-DOS, MS-DOS, PC DOS, OS/2, eComStation, ArcaOS, ISIS-II, iRMX 86, TRIPOS, AmigaDOS, Z80-RIO, OS-9, MSX-DOS, FlexOS, PC-MOS, SpartaDOS X, DR DOS, ROM-DOS, 4690 OS, FreeDOS, PTS-DOS, SISNE plus, Windows, ReactOS |
Platform | Cross-platform |
Type | Command |
License | MS-DOS: MIT PC-MOS: GPLv3 FreeDOS: GPLv2 ReactOS: LGPL-2.0-or-later |
In computing, format
is a command-line utility that carries out disk formatting. It is a component of various operating systems, including 86-DOS, MS-DOS, IBM PC DOS and OS/2, Microsoft Windows and ReactOS.
The command performs the following actions by default on a floppy disk, hard disk drive, solid state (USB), or other magnetic medium (it will not perform these actions on optical media):
Any storage device must have its medium structured to be useful. This process is referred to as "creating a filesystem" in Unix, Linux, or BSD.[4] Under these systems different commands are used. The commands can create many kinds of file systems, including those used by DOS, Windows, and OS/2.
FORMAT.COM
, among several other commands, in IBM PC DOS 1.0.FORMAT.CMD
in CP/M-86The command is also available in Intel ISIS-II,[5] iRMX 86,[6] MetaComCo TRIPOS,[7] AmigaDOS,[8] Zilog Z80-RIO,[9] Microware OS-9,[10] DR FlexOS,[11] TSL PC-MOS,[12] SpartaDOS X,[13] Datalight ROM-DOS,[14] IBM/Toshiba 4690 OS,[15] PTS-DOS,[16] SISNE plus,[17] and in the DEC RT-11[18] operating system.
On MS-DOS, the command is available in versions 1 and later.[19]
Optionally (by adding the /S, for "system" switch), format
can also install a Volume Boot Record. With this option, Format writes bootstrap code to the first sector of the volume (and possibly elsewhere as well). Format always writes a BIOS Parameter Block to the first sector, with or without the /S option.
Another option (/Q) allows for what Microsoft calls "Quick Format". With this option the command will not perform steps 2 and 3 above.[citation needed] Format /Q
does not alter data previously written to the media.
Typing "format" with no parameters in MS-DOS 3.2 or earlier would automatically, without prompting the user, format the current drive; however in MS-DOS 3.3 and later it would simply produce the error: "required parameter missing".[citation needed]
DR DOS 6.0 includes an implementation of the format
command.[20]
The FreeDOS version was developed by Brian E. Reifsnyder and is licensed under the GPL.[21]
format
command on ReactOSThe ReactOS implementation is based on a free clone developed by Mark Russinovich for Sysinternals in 1998. It is licensed under the GPL.[22] It was adapted to ReactOS by Emanuele Aliberti in 1999 and supports FAT, FAT32, FATX, EXT2, and BtrFS filesystems.