dir, short for ''directory'', is a

shell Shell may refer to: Architecture and design * Shell (structure), a thin structure ** Concrete shell, a thin shell of concrete, usually with no interior columns or exterior buttresses Science Biology * Seashell, a hard outer layer of a marine ani ...

command Command may refer to: Computing * Command (computing), a statement in a computer language * command (Unix), a Unix command * COMMAND.COM, the default operating system shell and command-line interpreter for DOS * Command key, a modifier key on A ...

for listing file system contents;

files File or filing may refer to: Mechanical tools and processes * File (tool), a tool used to remove fine amounts of material from a workpiece. **Filing (metalworking), a material removal process in manufacturing ** Nail file, a tool used to gentl ...

and directories. Arguably, the command provides the same essential functionality as the ls command, but typically the two commands are described as notably separate concepts, possibly since is implemented from a

codebase In software development, a codebase (or code base) is a collection of source code used to build a particular software system, application, or software component. Typically, a codebase includes only human-written source code system files; thu ...

that shares more history than many implementations. The command is often implemented as internal in the

operating system An operating system (OS) is system software that manages computer hardware and software resources, and provides common daemon (computing), services for computer programs. Time-sharing operating systems scheduler (computing), schedule tasks for ...

instead of as a separate application as many other commands are.

Implementations

Although syntax, semantics and implementations vary, a command is available in the

command-line interface A command-line interface (CLI) is a means of interacting with software via command (computing), commands each formatted as a line of text. Command-line interfaces emerged in the mid-1960s, on computer terminals, as an interactive and more user ...

(CLI) of the

Digital Research Digital Research, Inc. (DR or DRI) was a privately held American software company created by Gary Kildall to market and develop his CP/M operating system and related 8-bit, 16-bit and 32-bit systems like MP/M, Concurrent DOS, FlexOS, Multiuser ...

CP/M CP/M, originally standing for Control Program/Monitor and later Control Program for Microcomputers, is a mass-market operating system created in 1974 for Intel 8080/Intel 8085, 85-based microcomputers by Gary Kildall of Digital Research, Dig ...

MP/M MP/M (Multi-Programming Monitor Control Program) is a discontinued multi-user version of the CP/M operating system, created by Digital Research developer Tom Rolander in 1979. It allowed multiple users to connect to a single computer, each u ...

Intel Intel Corporation is an American multinational corporation and technology company headquartered in Santa Clara, California, and Delaware General Corporation Law, incorporated in Delaware. Intel designs, manufactures, and sells computer compo ...

ISIS-II, iRMX 86,

Cromemco Cromemco, Inc. was a Mountain View, California microcomputer company known for its high-end Z80-based S-100 bus computers and peripherals in the early days of the personal computer revolution. The company began as a partnership in 1974 between ...

CDOS,

MetaComCo MetaComCo (MCC) was a computer systems software company started in 1981 and based in Bristol, England by Peter Mackeonis and Derek Budge. A division of Tenchstar, Ltd. MetaComCo's first product was an MBASIC compatible interpreter for IBM PCs, ...

TRIPOS TRIPOS (''TRIvial Portable Operating System'') is a computer operating system. Development started in 1976 at the Computer Laboratory of Cambridge University and it was headed by Dr. Martin Richards. The first version appeared in January 1978 a ...

DOS DOS (, ) is a family of disk-based operating systems for IBM PC compatible computers. The DOS family primarily consists of IBM PC DOS and a rebranded version, Microsoft's MS-DOS, both of which were introduced in 1981. Later compatible syste ...

IBM International Business Machines Corporation (using the trademark IBM), nicknamed Big Blue, is an American Multinational corporation, multinational technology company headquartered in Armonk, New York, and present in over 175 countries. It is ...

Toshiba is a Japanese multinational electronics company headquartered in Minato, Tokyo. Its diversified products and services include power, industrial and social infrastructure systems, elevators and escalators, electronic components, semiconductors ...

4690 OS 4690 Operating System (sometimes shortened to 4690 OS or 4690) is a specially designed point of sale (POS) operating system, originally sold by IBM. In 2012, IBM sold its retail business, including this product, to Toshiba, which assumed support. ...

, IBM

OS/2 OS/2 is a Proprietary software, proprietary computer operating system for x86 and PowerPC based personal computers. It was created and initially developed jointly by IBM and Microsoft, under the leadership of IBM software designer Ed Iacobucci, ...

Microsoft Windows Windows is a Product lining, product line of Proprietary software, proprietary graphical user interface, graphical operating systems developed and marketed by Microsoft. It is grouped into families and subfamilies that cater to particular sec ...

, Singularity,

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 its headquarters is in Bothell, W ...

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 its headquarters is in Bothell, ...

ReactOS ReactOS is a Free and open-source software, free and open-source operating system for i586/amd64 personal computers that is intended to be binary-code compatibility, binary-compatible with computer programs and device drivers developed for Wind ...

GNU GNU ( ) is an extensive collection of free software (394 packages ), which can be used as an operating system or can be used in parts with other operating systems. The use of the completed GNU tools led to the family of operating systems popu ...

AROS AROS Research Operating System (AROS, pronounced "AR-OS") is a free and open-source multi media centric implementation of the AmigaOS 3.1 application programming interface (API) which is designed to be portable and flexible. , ports are availab ...

and in the DCL command-line interface used on DEC VMS,

RT-11 RT-11 (Real-time 11) is a discontinued small, low-end, single-user real-time operating system for the full line of Digital Equipment Corporation PDP-11 16-bit computers. RT-11 was first implemented in 1970. It was widely used for real-time compu ...

and

RSX-11 RSX-11 is a discontinued family of multi-user real-time operating systems for PDP-11 computers created by Digital Equipment Corporation. In widespread use through the late 1970s and early 1980s, RSX-11 was influential in the development of later ...

. It is also supplied with

OS/8 OS/8 is the primary operating system used on the Digital Equipment Corporation's PDP-8 minicomputer. PDP-8 operating systems which precede OS/8 include: * R-L Monitor, also referred to as MS/8. * P?S/8, requiring only 4K of memory. * PDP-8 4K ...

as a CUSP (Commonly-Used System Program). The dir command is supported by

Tim Paterson Tim Paterson (born 1 June 1956) is an American computer programmer, best known for creating 86-DOS, an operating system for the Intel 8086. This system emulated the application programming interface (API) of CP/M, which was created by Gary Kilda ...

's SCP

86-DOS 86-DOS (known internally as QDOS, for Quick and Dirty Operating System) is a discontinued operating system developed and marketed by Seattle Computer Products (SCP) for its Intel 8086-based computer kit. 86-DOS shared a few of its commands wi ...

. On

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 op ...

, the command is available in versions 1 and later. It is also available in the

open source Open source is source code that is made freely available for possible modification and redistribution. Products include permission to use and view the source code, design documents, or content of the product. The open source model is a decentrali ...

MS-DOS

emulator In computing, an emulator is Computer hardware, hardware or software that enables one computer system (called the ''host'') to behave like another computer system (called the ''guest''). An emulator typically enables the host system to run sof ...

DOSBox DOSBox is a free and open-source MS-DOS emulator. It supports running programs primarily video games that are otherwise inaccessible since hardware for running a compatible disk operating system (DOS) is obsolete and generally unavailab ...

prompts "

Abort, Retry, Fail? "Abort, Retry, Fail?" (or "Abort, Retry, Ignore?") is an error message found in DOS operating systems, which Command-line interface#Command prompt, prompts the user (computing), end-user for a course of action to follow. Although an improvement ...

" after being commanded to list a directory with no

diskette A floppy disk or floppy diskette (casually referred to as a floppy, a diskette, or a disk) is a type of disk storage composed of a thin and flexible disk of a magnetic storage medium in a square or nearly square plastic enclosure lined with a ...

in the drive. The File Transfer Protocol (

FTP The File Transfer Protocol (FTP) is a standard communication protocol used for the transfer of computer files from a server to a client on a computer network. FTP is built on a client–server model architecture using separate control and dat ...

) client program ftp is using dir command for listing remote directory. The

numerical computing Numerical analysis is the study of algorithms that use numerical approximation (as opposed to symbolic manipulations) for the problems of mathematical analysis (as distinguished from discrete mathematics). It is the study of numerical methods th ...

environments

MATLAB MATLAB (an abbreviation of "MATrix LABoratory") is a proprietary multi-paradigm programming language and numeric computing environment developed by MathWorks. MATLAB allows matrix manipulations, plotting of functions and data, implementat ...

and

GNU Octave GNU Octave is a scientific programming language for scientific computing and numerical computation. Octave helps in solving linear and nonlinear problems numerically, and for performing other numerical experiments using a language that is mostly ...

include a dir function with similar functionality.

Examples

DOS, Windows, ReactOS

List all files and directories in the current

working directory In computing, the working directory of a process is a directory of a hierarchical file system, if any, dynamically associated with the process. It is sometimes called the current working directory (CWD), e.g. the BSD getcwd function, or just c ...

. List any

text file A text file (sometimes spelled textfile; an old alternative name is flat file) is a kind of computer file that is structured as a sequence of lines of electronic text. A text file exists stored as data within a computer file system. In ope ...

s and

batch file A batch file is a Scripting language, script file in DOS, OS/2 and Microsoft Windows. It consists of a series of Command (computing), commands to be executed by the command-line interpreter, stored in a plain text file. A batch file may contain a ...

s (

filename extension A filename extension, file name extension or file extension is a suffix to the name of a computer file (for example, .txt, .mp3, .exe) that indicates a characteristic of the file contents or its intended use. A filename extension is typically d ...

".txt" or ".bat").

Recursively Recursion occurs when the definition of a concept or process depends on a simpler or previous version of itself. Recursion is used in a variety of disciplines ranging from linguistics to logic. The most common application of recursion is in m ...

list all files and directories in the specified directory and any subdirectories, in wide format, pausing after each screen of output. The directory name is enclosed in double-quotes, to prevent it from being interpreted is as two separate

command-line option A command-line interface (CLI) is a means of interacting with software via command (computing), commands each formatted as a line of text. Command-line interfaces emerged in the mid-1960s, on computer terminals, as an interactive and more user ...

s because it contains a

whitespace character A whitespace character is a character data element that represents white space when text is rendered for display by a computer. For example, a ''space'' character (, ASCII 32) represents blank space such as a word divider in a Western scrip ...

. List any

NTFS junction point NTFS links are the abstraction used in the NTFS file system—the default file system for all Microsoft Windows versions belonging to the Windows NT family—to associate pathnames and certain kinds of metadata, with entries in the NTFS Master ...

Unix

Traditionally,

Unix Unix (, ; trademarked as UNIX) is a family of multitasking, multi-user computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, a ...

and

Unix-like A Unix-like (sometimes referred to as UN*X, *nix or *NIX) operating system is one that behaves in a manner similar to a Unix system, although not necessarily conforming to or being certified to any version of the Single UNIX Specification. A Uni ...

systems use the command for the needs that dir satisfies. But, the

GNU operating system GNU ( ) is an extensive collection of free software (394 packages ), which can be used as an operating system or can be used in parts with other operating systems. The use of the completed GNU tools led to the family of operating systems popu ...

, has a dir command that "is equivalent to ls -C -b; that is, by default files are listed in columns, sorted vertically, and special characters are represented by backslash escape sequences". /www.gnu.org/software/coreutils/manual/html_node/dir-invocation.html dir invocation(GNU coreutils) at www.gnu.org Actually, for compatibility reasons, produces device-dependent output. The dir command, on the other hand, produces device-independent output.

References

External links

dir , Microsoft DocsOpen source DIR implementation that comes with MS-DOS v2.0Dir command syntax and examples
{{Windows commands CP/M commands Internal DOS commands Microcomputer software Microsoft free software MSX-DOS commands OS/2 commands ReactOS commands Windows commands Windows administration