In DOS, many standard system commands were provided for common tasks such as listing files on a disk or moving files. Some commands were built into the command interpreter, others existed as external commands on disk. Over the several generations of DOS, commands were added for the additional functions of the operating system. In the current Microsoft Windows operating system, a text-mode command prompt window, cmd.exe, can still be used.
The command interpreter for DOS runs when no application programs are running. When an application exits, if the transient portion of the command interpreter in memory was overwritten, DOS will reload it from disk. Some commands are internal — built into COMMAND.COM; others are external commands stored on disk. When the user types a line of text at the operating system command prompt, COMMAND.COM will parse the line and attempt to match a command name to a built-in command or to the name of an executable program file or batch file on disk. If no match is found, an error message is printed, and the command prompt is refreshed.
External commands were too large to keep in the command processor, or were less frequently used. Such utility programs would be stored on disk and loaded just like regular application programs but were distributed with the operating system. Copies of these utility command programs had to be on an accessible disk, either on the current drive or on the command path set in the command interpreter.
In the list below, commands that can accept more than one file name, or a filename including wildcards (* and ?), are said to accept a filespec (file specification) parameter. Commands that can accept only a single file name are said to accept a filename parameter. Additionally, command line switches, or other parameter strings, can be supplied on the command line. Spaces and symbols such as a "/" or a "-" may be used to allow the command processor to parse the command line into filenames, file specifications, and other options.
The command interpreter preserves the case of whatever parameters are passed to commands, but the command names themselves and file names are case-insensitive.
Many commands are the same across many DOS systems, but some differ in command syntax or name.
A partial list of the most common commands for MS-DOS follows below.
Sets the path to be searched for data files or displays the current search path. The APPEND command is similar to the PATH command that tells DOS where to search for program files (files with a .COM, . EXE, or .BAT file name extension).
The command redirects requests for disk operations on one drive to a different drive. It can also display drive assignments or reset all drive letters to their original assignments. The command is available in MS-DOS 5.00.
Attrib changes or views the attributes of one or more files. It defaults to display the attributes of all files in the current directory. The file attributes available include read-only, archive, system, and hidden attributes. The command has the capability to process whole folders and subfolders of files and also process all files
These are commands to backup and restore files from an external disk. These appeared in version 2, and continued to PC DOS 5 and MS-DOS 6 (PC DOS 7 had a deversioned check). In DOS 6, these were replaced by commercial programs (CPBACKUP, MSBACKUP), which allowed files to be restored to different locations.
An implementation of the BASIC programming language for PCs. Implementing BASIC in this way was very common in operating systems on 8- and 16-bit machines made in the 1980s.
IBM computers had BASIC 1.1 in ROM, and IBM's versions of BASIC used code in this ROM-BASIC, which allowed for extra memory in the code area. BASICA last appeared in IBM PC DOS 5.02, and in OS/2 (2.0 and later), the version had ROM-BASIC moved into the program code.
Microsoft released GW-BASIC for machines with no ROM-BASIC. Some OEM releases had basic.com and basica.com as loaders for GW-BASIC.EXE.
BASIC was dropped after MS-DOS 4, and PC DOS 5.02. OS/2 (which uses PC DOS 5), has it, while MS-DOS 5 does not.
Starts a batch file from within another batch file and returns when that one ends.
The CHDIR (or the alternative name CD) command either displays or changes the current working directory.
CHKDSK verifies a storage volume (for example, a hard disk, disk partition or floppy disk) for file system integrity. The command has the ability to fix errors on a volume and recover information from defective disk sectors of a volume.
The CHOICE command is used in batch files to prompt the user to select one item from a set of single-character choices. Choice was introduced as an external command with MS-DOS 6.0; Novell DOS 7 and PC DOS 7.0. Earlier versions of DR DOS supported this function with the built-in switch command (for numeric choices) or by beginning a command with a question mark. This command was formerly called ync (yes-no-cancel).
The CLS or CLRSCR command clears the terminal screen.
Start a new instance of the command interpreter.
Show differences between any two files, or any two sets of files.
Makes copies of existing files.
Defines the terminal device (for example, COM1) to use for input and output.
A disk compression utility supplied with MS-DOS starting from version 6.0 in 1993.
A very primitive assembler and disassambler.
DEL (or the alternative form ERASE) is used to delete one or more files.
Deletes a directory along with all of the files and subdirectories that it contains. Normally, it will ask for confirmation of the potentially dangerous action. Since the RD (RMDIR) command can not delete a directory if the directory is not empty, the DELTREE command can be used to delete the whole directory.
deltree command is included in certain versions of Microsoft Windows and Microsoft DOS Operating Systems. It is specifically available only in versions of MS-DOS 6.0 and higher, and in Microsoft Windows 9x. In Windows NT, the functionality provided exists but is handled by the command rd or rmdir which has slightly different syntax. This command has been deprecated for Windows 7.
The DIR command displays the contents of a directory. The contents comprise the disk's volume label and serial number; one directory or filename per line, including the filename extension, the file size in bytes, and the date and time the file was last modified; and the total number of files listed, their cumulative size, and the free space (in bytes) remaining on the disk. The command is one of the few commands that exist from the first versions of DOS. The command can display files in subdirectories. The resulting directory listing can be sorted by various criteria and filenames can be displayed in a chosen format.
A command for comparing the complete contents of a floppy disk to another one.
A command for copying the complete contents of a diskette to another diskette.
The ECHO command prints its own arguments back out to the DOS equivalent of the standard output stream. (Hence the name, ECHO) Usually, this means directly to the screen, but the output of echo can be redirected, like any other command, to files or devices. Often used in batch files to print text out to the user.
Another important use of the echo command is to toggle echoing of commands on and off in batch files. Traditionally batch files begin with the
@echo off statement. This says to the interpreter that echoing of commands should be off during the whole execution of the batch file, thus resulting in a "tidier" output (the
@ symbol declares that this particular command (echo off) should also be executed without echo.)
EDIT is a full-screen text editor, included with MS-DOS 5 and 6, OS/2 and Windows NT to 4.0 The corresponding program in Windows 95 and later, and W2k and later is Edit v2.0. PC DOS 6 and later use the DOS E Editor and DR-DOS used editor up to version 7.
DOS line-editor. It can be used with a script file, like debug, this makes it of some use even today. The absence of a console editor in MS-DOS/PC DOS 1-4 created an after-market for third-party editors.
In DOS 5, an extra command "?" was added to give the user much-needed help.
DOS 6 was the last version to contain EDLIN; for MS-DOS 6, it's on the supplemental disks, while PC DOS 6 had it in the base install. Windows NT 32-bit, and OS/2 have Edlin.
Exits the current command processor. If the exit is used at the primary command, it has no effect unless in a DOS window under Microsoft Windows, in which case the window is closed and the user returns to the desktop.
Provides information for MS-DOS commands.
A command that provides accelerated access to frequently-used files and directories.
Show differences between any two files, or any two sets of files.
The FDISK command manipulates hard disk partition tables. The name derives from IBM's habit of calling hard drives fixed disks. FDISK has the ability to display information about, create, and delete DOS partitions or logical DOS drive. It can also install a standard master boot record on the hard drive.
The FOR loop can be used to parse a file or the output of a command.
Deletes the FAT entries and the root directory of the drive/partition, and reformats it for MS-DOS. In most cases, this should only be used on floppy drives or other removable media. This command can potentially erase everything on a computer's drive.
A TSR program to enable the sending of graphical screen dump to printer by pressing <Print Screen>.
Gives help about DOS commands.
Evaluate the condition, and only if it is true, then it execute the remainder of the command line Otherwise, it skips the remainder of the line and continues with next command line.
Used in Batch files.
In MS-DOS; filelink in DR-DOS.
Network PCs using a null modem cable or LapLink cable. The server-side version of InterLnk, it also immobilizes the machine it's running on as it is an active app (As opposed to a TSR app) which must be running for any transfer to take place. DR-DOS' filelink is executed on both the client and server.
New in PC DOS 5.02, MS-DOS 6.0
Changes the label on a logical drive, such as a hard disk partition or a floppy disk.
Loads a program above the first 64K of memory, and runs the program. The command is included only in MS-DOS/PC DOS. DR-DOS used memmax, which opened or closed lower, upper, and video memory access, to block the lower 64K of memory.
A command that loads a program into the upper memory area.
The command is called hiload in DR-DOS.
Makes a new directory. The parent of the directory specified will be created if it does not already exist.
Displays memory usage. It is capable of displaying program size and status, memory in use, and internal drivers.It is internal command.
Starting with version 6, MS-DOS included the external program MemMaker which was used to free system memory (especially Conventional memory) by automatically reconfiguring the AUTOEXEC.BAT and CONFIG.SYS files. This was usually done by moving TSR programs and device drivers to the upper memory. The whole process required two system restarts. Before the first restart the user was asked whether he/she wanted to enable EMS Memory, since use of expanded memory required a reserved 64KiB region in upper memory. The first restart inserted the SIZER.EXE program which gauged the memory needed by each TSR or Driver. MemMaker would then calculate the optimal Driver and TSR placement in upper memory and modify the AUTOEXEC.BAT and CONFIG.SYS accordingly, and reboot the second time.
MEMMAKER.EXE and SIZER.EXE were developed for Microsoft by Helix Software Company and were eliminated starting in MS DOS 7 / Windows 95. PC DOS uses another program RamBoost to optimize memory, working either with PC DOS's HIMEM/EMM386 or a third-party memory manager. RamBoost was licensed to IBM by Central Point Software.
The MORE command paginates text, so that one can view files containing more than one screen of text. More may also be used as a filter. While viewing MORE text, the return key displays the next line, the space bar displays the next page.
Moves files or renames directories. DR-DOS used a separate command for renaming directories,
The MSD command provides detailed technical information about the computer's hardware and software. MSD was new in MS-DOS 6; the PC DOS version of this command is QCONFIG. The command appeared first in Word2, and then in Windows 3.10.
Displays or sets a search path for executable files.
Suspends processing of a batch program and displays the message 'Press any key to continue. . .', if not given other text to display.
The PRINT command adds or removes files in the print queue. This command was introduced in MS-DOS version 2. Before that there was no built-in support for background printing files. The user would usually use the copy command to copy files to LPT1.
The PROMPT command allows the user to change the prompt in the command screen. The default prompt (in Windows 10) is $p (i.e. prompt $p), which displays the drive and current path as the prompt, but can be changed to anything. 'Prompt $d', displays the current system date as the prompt. Type 'prompt /?' in the cmd screen for help on this function.
Remove a directory (delete a directory); by default the directories must be empty of files for the command to succeed. The deltree command in some versions of MS-DOS and all versions of Windows 9x removes non-empty directories.
A primitive filesystem error recovery utility included in MS-DOS / IBM PC DOS.
Remark (comment) command, normally used within a batch file, and for DR-DOS, PC/MS-DOS 6 and above, in CONFIG.SYS. This command is processed by the command processor. Thus, its output can be redirected to create a zero-byte file. REM is useful in logged sessions or screen-captures. One might add comments by way of labels, usually starting with double-colon (::). These are not processed by the command processor.
The REN command renames a file. Unlike the
move command, this command cannot be used to rename subdirectories, or rename files across drives. Mass renames can be accomplished by the use of the wildcards characters asterisk (*) and question mark (?).
See: BACKUP and RESTORE
Disk diagnostic utility. Scandisk was a replacement for the
chkdsk utility, starting with later versions of MS-DOS. Its primary advantages over
chkdsk is that it is more reliable and has the ability to run a surface scan which finds and marks bad clusters on the disk. It also provided mouse point-and-click TUI, allowing for interactive session to complement command-line batch run.
chkdsk had surface scan and bad cluster detection functionality included, and was used again on Windows NT based operating systems.
Sets environment variables. cmd.exe in Windows NT 2000, 4DOS, 4OS2, 4NT, and a number of third-party solutions allow direct entry of environment variables from the command prompt. From at least Windows 2000, the
set command allows for the evaluation of strings into variables, thus providing inter alia a means of performing integer arithmetic.
SetVer is a TSR program designed to return a different value to the version of DOS that is running. This allows programs that look for a specific version of DOS to run under a different DOS.
Setver appeared in version 4, and has been in every version of DOS, OS/2 and Windows NT since.
Installs support for file sharing and locking capabilities.
A command that changes the position of replaceable parameters in a batch file.
A utility to make a volume bootable. Sys rewrites the Volume Boot Code (the first sector of the partition that SYS is acting on) so that the code, when executed, will look for IO.SYS. SYS also copies the core DOS system files, IO.SYS, MSDOS.SYS, and COMMAND.COM, to the volume. SYS does not rewrite the Master Boot Record, contrary to widely held belief.
Enables a user to change the title of their MS-DOS window.
It is an external command, graphically displays the path of each directory and sub-directories on the specified drive.
The TRUENAME command will expand the name of a file, directory, or drive, and display the result. It will expand an abbreviated form which the command processor can recognise into its full form. It can see through SUBST and JOIN to find the actual directory.
MS-DOS can find files and directories given their names, without full path information, if the search object is on a path specified by the environment variable PATH. For example, if PATH includes C:\PROGRAMS, and file MYPROG.EXE is on this directory, then if
MYPROG is typed at the command prompt, the command processor will execute
C:\PROGRAMS\MYPROG.EXE. In this case,
This command displays the UNC pathnames of mapped network or local CD drives. This command is an undocumented DOS command. The help switch "/?" defines it as a "Reserved command name". It is available in MS-DOS 5.00.0. This command is similar to the which command, which, given an executable found in $PATH, would give a full path and name. The C library function
realpath performs this function. The Microsoft Windows command processors do not support this command.
Displays a file. The more command is frequently used in conjunction with this command, e.g. type long-text-file | more. TYPE can be used to concatenate files (type file1 file2 > file3); however this won't work for large files—use copy command instead.
Restores file previously deleted with del. By default all recoverable files in the working directory are restored; options are used to change this behavior. If the MS-DOS mirror TSR program is used, then deletion tracking files are created and can be used by undelete.
An internal DOS command, that reports the DOS version presently running, and since MS-DOS 5, whether DOS is loaded high.
Enables or disables the feature to determine if files have been correctly written to disk. If no parameter is provided, the command will display the current setting.
An internal command that displays the disk volume label and serial number.
A TSR program that continuously monitors the computer for viruses.
Copy entire directory trees. Xcopy is a version of the copy command that can move files and directories from one location to another.
There are several guides to DOS commands available that are licensed under the GNU Free Documentation License:
In computing, ATTRIB is a command in ISIS-II, DOS, OS/2, Microsoft Windows and ReactOS that allows the user to change various characteristics, or "attributes" of a computer file or directory. The command is also available in the EFI shell.Choice (command)
In computing, choice is a command that allows for batch files to prompt the user to select one item from a set of single-character choices.Comp (command)
In computing, comp is a command used on OS/8, DOS, FlexOS, OS/2, Microsoft Windows and related computer operating systems such as ReactOS. It is used to perform comparisons of multiple computer files to show the differences between them.
In DOS, the comp command first appeared in PC DOS 1.0 and has been included in most versions of MS-DOS and PC DOS. A newer command, fc was added in DOS 3.3 which allows for line comparisons in addition to binary comparisons.
The FreeDOS version was developed by Paul Vojta.The command is also available in the EFI shell.Del (command)
In computing, del (or erase) is a command in command-line interpreters (shells) such as COMMAND.COM, cmd.exe, 4DOS, NDOS, 4OS2, 4NT and Windows PowerShell. It is used to delete one or more files or directories from a file system.Dir (command)
In computing, dir (directory) is a command used for computer file and directory listing.Echo (command)
In computing, echo is a command that outputs the strings it is being passed as arguments. It is a command typically used in shell scripts and batch files to output status text to the screen or a computer file, or as a source part of a pipeline.Exe2bin
The command-line tool exe2bin is a post-compilation utility program available on MS-DOS and other operating systems.Exit (command)
In computing, exit is a command used in many operating system command-line shells and scripting languages.
The command causes the shell or program to terminate. If performed within an interactive command shell, the user is logged out of their current session, and/or user's current console or terminal connection is disconnected. Typically an optional exit code can be specified, which is typically a simple integer value that is then returned to the parent process.
Operating systems, shells and scripting languages providing this command include OS/2, FlexOS, MPE/iX
, KolibriOS, SymbOS, cmd.exe, sh, ksh, Perl, AWK, PHP, TCL, PowerShell and others.
The command is also available in the open source MS-DOS emulator DOSBox.
The numerical computing environment MATLAB includes an exit function with similar functionality.File Compare
In computing, fc (File Compare) is a command-line program in DOS, OS/2 and Microsoft Windows operating systems, that compares multiple files and outputs the differences between them. It is similar to the Unix commands comm, cmp and diff.Microsoft ScanDisk
Microsoft ScanDisk (also called ScanDisk), is a diagnostic utility included in MS-DOS and Windows 9x. It checks and repairs file systems errors on a disk drive.Mkdir
The mkdir (make directory) command in the Unix, DOS, FlexOS, OS/2, Microsoft Windows, and ReactOS operating systems is used to make a new directory. It is also available in the EFI shell and in the PHP scripting language. In DOS, OS/2, Windows and ReactOS, the command is often abbreviated to md.
The command is analogous to the OpenVOS create_dir command. TRIPOS and AmigaDOS provide a similar MakeDir command to create new directories. The numerical computing environments MATLAB and GNU Octave include an mkdir
function with similar functionality.Outline of Microsoft
Microsoft Corporation is a multinational corporation based in Redmond, Washington, USA and founded by Bill Gates and Paul Allen that develops, manufactures, licenses, and supports a wide range of products and services predominantly related to computing. Due to the scope and size of the company, it encompasses a broad range of topics mostly revolving around critical analysis and the company's products and services.Recover (command)
In computing, recover was a primitive filesystem error recovery utility included in MS-DOS / IBM PC DOS versions prior to DOS 6.0.Replace (command)
In computing, replace is a command that is used to replace one or more existing computer files or add new files to a target directory.Rmdir
rmdir (or rd) is a command which will remove an empty directory on a Unix (e.g. macOS, Solaris, AIX, HP-UX), Unix-like (e.g. FreeBSD, Linux), DOS, FlexOS, OS/2, Microsoft Windows or ReactOS operating system.
The command is also available in the open source MS-DOS emulator DOSBox. The numerical computing environments MATLAB and GNU Octave include an rmdir
function with similar functionality.TIME (command)
In computing, TIME is a command in DOS, OS/2, Microsoft Windows and ReactOS that is used to display and set the current system time of the operating system. It is included in command-line interpreters (shells) such as COMMAND.COM, CMD.EXE, 4DOS, 4OS2 and 4NT.
The command is also available in the DEC RT-11 operating system and in the EFI shell.
In Unix, the date command displays and sets both the time and date, in a similar manner.TYPE (DOS command)
In computing, type is a command in various command-line interpreters (shells) such as COMMAND.COM, cmd.exe, 4DOS/4NT and Windows PowerShell used to display the contents of specified files on the computer terminal. The analogous Unix command is cat.Tree (command)
In computing, tree is a recursive directory listing command or program that produces a depth-indented listing of files. It is available in Unix and Unix-like systems, as well as MS-DOS, FlexOS, 4690 OS, PTS-DOS, FreeDOS, OS/2, Microsoft Windows, and ReactOS.Vol (command)
In some operating systems (e.g., DOS, FlexOS, 4690 Operating System, OS/2, Microsoft Windows and ReactOS) vol is a command within the command line interpreters (shells) such as COMMAND.COM and cmd.exe. It is used to display the volume label and volume serial number on a logical drive, such as a hard disk partition or a floppy disk, if they exist.
The command is also available in the EFI shell.