Comparison of command shells

Template:Short description Script error: No such module "labelled list hatnote". Template:More citations needed Template:Use dmy dates

File:Bash screenshot.png

Screen shot of a terminal showing various Bash commands and resulting output.

This article catalogs comparable aspects of notable operating system shells.

General characteristics

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Shell	Usual environmentScript error: No such module "Check for unknown parameters".	Usually invokedScript error: No such module "Check for unknown parameters".	IntroducedScript error: No such module "Check for unknown parameters".	Platform-independentScript error: No such module "Check for unknown parameters".	Default login shell inScript error: No such module "Check for unknown parameters".	Default script shell inScript error: No such module "Check for unknown parameters".	LicenseScript error: No such module "Check for unknown parameters".	Source code availabilityScript error: No such module "Check for unknown parameters".	User interfaceScript error: No such module "Check for unknown parameters".	Mouse supportScript error: No such module "Check for unknown parameters".	Unicode supportScript error: No such module "Check for unknown parameters".	ISO 8601 supportScript error: No such module "Check for unknown parameters".	Console redirectionScript error: No such module "Check for unknown parameters".	Stream redirectionScript error: No such module "Check for unknown parameters".	ConfigurabilityScript error: No such module "Check for unknown parameters".	Startup/shutdown scriptsScript error: No such module "Check for unknown parameters".	Batch scriptsScript error: No such module "Check for unknown parameters".	LoggingScript error: No such module "Check for unknown parameters".	Available as statically linked, independent single file executableScript error: No such module "Check for unknown parameters".
Thompson shell	UNIX	sh	1971	Template:N/A	UNIX	UNIX	Template:N/A	Yes	Text-based CLI	No	No	Template:N/A	Yes	Template:N/A	Template:N/A	Template:N/A	Template:N/A	Template:N/A	Template:N/A
Bourne shell 1977 version	7th Ed. UNIX	sh	1977	Yes^[1]	7th Ed. UNIX	7th Ed. UNIX,	Template:Proprietary	Yes	Text-based CLI	No	No	Template:N/A	Yes	Yes (Template:Citation needed span)Script error: No such module "Check for unknown parameters".	Yes (via variables and options)Script error: No such module "Check for unknown parameters".	Yes (Template:Mono)Script error: No such module "Check for unknown parameters".	Yes (Unix feature)Script error: No such module "Check for unknown parameters".	No	Yes
Bourne shell current version	Various UNIX	sh	1977	Yes^[2]	SunOS-5.x, FreeBSD^[3]	SunOS-5.x	CDDL^[4]Template:Better source needed	Yes	Text-based CLI	No	Yes^{[nb 1]}Template:Better source needed	Template:N/A	Yes	Yes (Template:Citation needed span)Script error: No such module "Check for unknown parameters".	Yes (via variables and options)Script error: No such module "Check for unknown parameters".	Yes (Template:Mono)Script error: No such module "Check for unknown parameters".	Yes (Unix feature)Script error: No such module "Check for unknown parameters".	Yes^{[nb 2]}	Yes
POSIX shell^[5]	POSIX	sh	1992^[6]	Template:N/A	Template:N/A	POSIX	Template:N/A	Template:N/A	Text-based CLI	No	Yes if used by configured localeScript error: No such module "Check for unknown parameters".	Template:N/A	Yes	Yes (Template:Citation needed span)Script error: No such module "Check for unknown parameters".	Yes (via variables and options)Script error: No such module "Check for unknown parameters".	Unspecified (Template:Mono given as an example)	Yes (Unix feature)Script error: No such module "Check for unknown parameters".	Yes	Template:N/A
bash (v4)	POSIX	bash, sh	1989^[7]	Yes	GNU, Linux (default for root), macOS 10.3–10.14	GNU, Linux, Haiku, macOS 10.3–10.14	GPL	Yes	Text-based CLI	No	Yes^[8]Template:Better source needed	Yes (Template:Mono builtin)Script error: No such module "Check for unknown parameters".	Yes	Yes (Template:Citation needed span)Script error: No such module "Check for unknown parameters".	Yes (via variables and options)Script error: No such module "Check for unknown parameters".	Yes (Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	Yes (Unix feature)Script error: No such module "Check for unknown parameters".	Yes	Yes
csh	POSIX	csh	1978	Yes	SunOS	?	BSD	Yes	Text-based CLI	No	No	?	Yes	Yes (Template:Mono, Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	Yes (via variables and options)Script error: No such module "Check for unknown parameters".	Yes (Template:Mono, Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	Yes (Unix feature)Script error: No such module "Check for unknown parameters".	Yes	Yes
tcsh	POSIX	tcsh, csh	1983^[9]	Yes	FreeBSD (former default for root),^[10] formerly Mac OS X	?	BSD	Yes	Text-based CLI	No	Yes	?	Yes	Yes (Template:Mono, Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	Yes (via variables and options)Script error: No such module "Check for unknown parameters".	Yes (Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	Yes (Unix feature)Script error: No such module "Check for unknown parameters".	Yes	Yes
Hamilton C shell	Win32, OS/2	csh	1988^[11]	Yes (OS/2 version no longer maintained)Script error: No such module "Check for unknown parameters".	Optional	Optional	Template:Proprietary	No	Text-based CLI	No	No	Yes (-t timestamp operator)Script error: No such module "Check for unknown parameters".	Yes	Yes (Template:Mono, Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	Yes (via variables and options)Script error: No such module "Check for unknown parameters".	Yes (via login.csh, startup.csh and logout.csh)Script error: No such module "Check for unknown parameters".	Yes (command line option)Script error: No such module "Check for unknown parameters".	Yes	Yes
Scsh	POSIX	scsh	1994	Yes	?	?	BSD-style	Yes	?	?	?	?	?	Yes	?	?	?	?	Yes
ksh (ksh93t+)	POSIX	ksh	1983^[12]^[13]	Yes	AIX, HP-UX	OpenSolaris	Common Public License	Yes	Text-based CLI	No	Yes	Yes (Template:Mono builtin with Template:Mono^[14])Script error: No such module "Check for unknown parameters".	Yes	Yes (Template:Mono up to 9)^[14]Script error: No such module "Check for unknown parameters".	Yes (via variables and options)Script error: No such module "Check for unknown parameters".	Yes (system and user's Template:Mono and Template:Mono)Script error: No such module "Check for unknown parameters".	Yes (Unix feature)Script error: No such module "Check for unknown parameters".	Yes	Yes
pdksh	POSIX	ksh, sh	1989?	Yes	OpenBSD^[15]	OpenBSD^[15]	Public domain	Yes	Text-based CLI	No	No	Template:N/A	Yes	Yes (Template:Citation needed span)Script error: No such module "Check for unknown parameters".	Yes (via variables and options)Script error: No such module "Check for unknown parameters".	Yes (Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	Yes (Unix feature)Script error: No such module "Check for unknown parameters".	Yes	Yes
zsh	POSIX	zsh	1990	Yes	Deepin, GoboLinux, Grml, macOS 10.15+, Kali 2020.4+	Grml, macOS 10.15+	MIT-style	Yes	Text-based CLI	Yes via additional code^[16]Script error: No such module "Check for unknown parameters".	Yes	Yes (various internal features involving the date, by using the Template:Mono Template:Mono format^[17] and the Template:Mono option for the Template:Mono builtin^[18])Script error: No such module "Check for unknown parameters".	Yes	Yes (Template:Mono up to 9)^[19]Script error: No such module "Check for unknown parameters".	Yes (via variables, options, functions, styles, etc.)Script error: No such module "Check for unknown parameters".	Yes (system and user's Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	Yes (Unix feature)Script error: No such module "Check for unknown parameters".	Yes	Yes
ash	POSIX	sh	1989	Yes	Minix, BusyBox based systems	NetBSD, Minix, BusyBox based systems	BSD-style	Yes	Text-based CLI	No	Partial (for BusyBox, supported in command-line editing, but not in string handling^[20])Script error: No such module "Check for unknown parameters".	Template:N/A	Yes	Yes (Template:Citation needed span)Script error: No such module "Check for unknown parameters".	Yes (via variables and options)Script error: No such module "Check for unknown parameters".	Yes (Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	Yes (Unix feature)Script error: No such module "Check for unknown parameters".	Yes	Yes
CCP	CP/M, MP/M	(CCP)	1976 (1974)	No	CP/M (no login), MP/M	CP/M, MP/M	Template:Proprietary	Yes (originally closed-source)	Text-based CLI	No	No	No	No	No	No	Yes (automatic via Template:Mono)	Partial (only via external Template:Mono command to update Template:Mono)Script error: No such module "Check for unknown parameters".	No	Yes
COMMAND.COM	DOS	COMMAND	1980	No (3rd party implementations, not bound to a specific DOS vendor or version, available)Script error: No such module "Check for unknown parameters".	DOS, Windows 95, 98, SE, ME	DOS, Windows 95, 98, SE, ME	vendor specific, f.e. MS-EULA,^{[nb 3]} or BSD/GPL (free clones)	No (except for OpenDOS, DR-DOS, PTS/DOS and FreeDOS)	Text-based CLI	No	No	No (except for DR-DOS)	Yes (via Template:Mono or Template:Mono)	Yes (Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	Yes (via startup parameters and environment variables, DR-DOS also supports Template:Mono user-default switch command)	Yes (automatic Template:Mono for primary shell, or explicitly via Template:Mono, Template:Mono or Template:Mono startup options)	Yes (via Template:Mono command or Template:Mono and Template:Mono startup options)	No	Yes
OS/2 CMD.EXE	OS/2, eComStation, ArcaOS	CMD	1987	No	OS/2, eComStation, ArcaOS	OS/2, eComStation, ArcaOS	Template:Proprietary^{[nb 4]}	No	Text-based CLI	No	No	No	No	Yes (Template:Mono, Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	?	Partial (only via Template:Mono startup option)	Yes (via Template:Mono command or Template:Mono and Template:Mono startup options)	No	Yes
Windows CMD.EXE^{[nb 5]}	Win32	CMD	1993	No	Windows NT, 2000, XP, Server 2003, Vista	Windows NT, 2000, XP, Server 2003, Vista	Template:Proprietary^{[nb 6]}	No	Text-based CLI	No	Partial (Template:Mono for UTF-8, but program arguments are still encoded in local codepage)	No	No	Yes	Yes (via registry, startup parameters, and environment variables)	Yes (automatic via registry, or explicitly via Template:Mono startup option)	Yes (via Template:Mono command or Template:Mono and Template:Mono startup options)	No	Yes
4DOS, NDOS	DOS, Windows 95, 98, SE, ME	4DOS, NDOS	1989 (1986)	No (not bound to a specific OS vendor or version)Script error: No such module "Check for unknown parameters".	Optional	Optional	MIT License, with restrictions	Yes	Text-based CLI with TUI extensions	Yes (popups, help system, Template:Mono internal variable, Template:Mono command)	No	Yes	Yes (via Template:Mono, except for Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono commands and file / directory coloring)	Yes (Template:Mono, Template:Mono, Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	Yes (via Template:Mono/Template:Mono file, startup parameters, environment variables, Template:Mono command)	Yes (automatic Template:Mono for primary shell and Template:Mono/Template:Mono as well as Template:Mono/Template:Mono for any shell, or explicitly via Template:Mono, Template:Mono or Template:Mono startup options)	Yes (via Template:Mono command or Template:Mono and Template:Mono startup options)	Yes	Yes
4OS2	OS/2, eComStation, ArcaOS	4OS2	1992	No (not bound to specific OS/2 versions)Script error: No such module "Check for unknown parameters".	Optional (but bundled with ArcaOS)	Optional	Template:Proprietary	Yes	Text-based CLI	No	No	No	No	Yes (Template:Mono, Template:Mono, Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	Yes (via Template:Mono file, startup parameters, environment variables, Template:Mono command)	Yes (automatic via Template:Mono/Template:Mono as well as Template:Mono/Template:Mono files, or explicitly via Template:Mono option)	Yes (via Template:Mono command or Template:Mono and Template:Mono startup options)	Yes	?
TCC (formerly 4NT)	Win32	TCC	1993	No (not bound to specific NT versions)Script error: No such module "Check for unknown parameters".	optional	optional	Template:Proprietary	No	Text-based CLI (Take Command: GUI)	Yes (console mouse, popups, help system, Template:Mono, Template:Mono internal variables, Template:Mono command)Script error: No such module "Check for unknown parameters".	Yes	Yes	No	Yes (Template:Mono, Template:Mono, Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	Yes (via registry, Template:Mono/Template:Mono file, startup parameters, environment variables, Template:Mono command)Script error: No such module "Check for unknown parameters".	Yes (automatic via registry and Template:Mono/Template:Mono as well as Template:Mono/Template:Mono, or explicitly via Template:Mono startup option)Script error: No such module "Check for unknown parameters".	Yes (via Template:Mono command or Template:Mono and Template:Mono startup options)Script error: No such module "Check for unknown parameters".	Yes	No
VMS DCL^[21]	OpenVMS	Automatically for login/interactive processScript error: No such module "Check for unknown parameters".	1977?	Yes	VMS	VMS	Proprietary, bundled in VMS	by special license only	Text-based CLI	with DECwindows/Motif	Yes	Yes, at least to 1988 standard	Yes	Yes (Template:Mono, Template:Mono assignment)Script error: No such module "Check for unknown parameters".	Yes (via symbols, logical names, and options)Script error: No such module "Check for unknown parameters".	Yes (SYS$MANAGER:SYLOGIN.COM and user defined LOGIN.COM)Script error: No such module "Check for unknown parameters".	Yes	Yes	No
PowerShell	.NET, .NET Framework	PowerShell	2006	Yes	Windows 10, 8, Server 2008, 7^{[nb 7]}	Windows 10, 8, Server 2008, 7	MIT-style	Yes	Graphical CLI	Yes	Yes	Yes	Yes	Yes	Yes (via variables and options)Script error: No such module "Check for unknown parameters".	Yes (%USERPROFILE%\Documents \WindowsPowerShell\Microsoft.PowerShell_profile.ps1)Script error: No such module "Check for unknown parameters".	Yes (PowerShell feature)Script error: No such module "Check for unknown parameters".	Yes	No
rc	Plan 9, POSIX	rc	1989	Yes	Plan 9, Version 10 Unix	Plan 9, Version 10 Unix	MIT License^[22]	Yes	Text-based CLI	?	Yes	Yes	?	Yes	Yes (via options)Script error: No such module "Check for unknown parameters".	Yes (Template:Mono)Script error: No such module "Check for unknown parameters".	Yes	?	Yes
BeanShell	Java	?	2005	Yes	?	?	LGPL	?	?	?	Yes	?	?	Yes	?	?	?	?	No
fish	POSIX	fish	2005^[23]	Yes	GhostBSD	?	GPL	Yes	Text-based CLI	?	Yes	?	?	Yes (Template:Citation needed span)Script error: No such module "Check for unknown parameters".	Yes (through environment variables and via web interface through Template:Mono)Script error: No such module "Check for unknown parameters".	Yes (Template:Mono and Template:Mono)Script error: No such module "Check for unknown parameters".	Yes (Unix feature)Script error: No such module "Check for unknown parameters".	Yes (Template:Mono)Script error: No such module "Check for unknown parameters".	?
Ion	Redox, Linux	ion	2015^[24]	Yes	Redox	Redox	MIT	Yes	Text-based CLI	?	Yes	Yes	?	Yes (Template:Citation needed span)Script error: No such module "Check for unknown parameters".	Yes (follows the XDG Base Directory spec)Script error: No such module "Check for unknown parameters".	Yes (Template:Mono)Script error: No such module "Check for unknown parameters".	Yes	Yes (Template:Mono)Script error: No such module "Check for unknown parameters".	Partial (not distributed as a standalone executable, but it can be built as one)
Shell	Usual environment	Usually invoked	Introduced	Platform-independent	Default login shell in	Default script shell in	License	Source code availability	User interface	Mouse support	Unicode support	ISO 8601 support	Console redirection	Stream redirection	Configurability	Startup/shutdown scripts	Batch scripts	Logging	Available as statically linked, independent single file executable

Interactive features

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Shell	Command name completionScript error: No such module "Check for unknown parameters".	Path completionScript error: No such module "Check for unknown parameters".	Command argument completionScript error: No such module "Check for unknown parameters".	Wildcard completionScript error: No such module "Check for unknown parameters".	Command historyScript error: No such module "Check for unknown parameters".	Mandatory argument promptScript error: No such module "Check for unknown parameters".	Automatic suggestionsScript error: No such module "Check for unknown parameters".	Colored directory listingsScript error: No such module "Check for unknown parameters".	Text highlightingScript error: No such module "Check for unknown parameters".	Syntax highlightingScript error: No such module "Check for unknown parameters".	Directory history, stack or similar featuresScript error: No such module "Check for unknown parameters".	Implicit directory changeScript error: No such module "Check for unknown parameters".	AutocorrectionScript error: No such module "Check for unknown parameters".	Integrated environmentScript error: No such module "Check for unknown parameters".	SnippetsScript error: No such module "Check for unknown parameters".	Value promptScript error: No such module "Check for unknown parameters".	Menu/options promptScript error: No such module "Check for unknown parameters".	Progress indicatorScript error: No such module "Check for unknown parameters".	Context sensitive helpScript error: No such module "Check for unknown parameters".
Thompson shell	No	No	No	No	No	No	No	?	?	No	No	No	No	No	No	No	No	No	No
Bourne shell 1977 version	No	No	No	No	No	No	No	?	?	No	No	No	No	No	No	Yes	No	External	No
Bourne shell current version	No	Yes^{[nb 8]}	No	No	Yes^{[nb 8]}	No	No	Yes	Yes	No	Yes (CDPATH, pushd, popd, dirs), CDPATH since SVr4	No	No	No	No	Yes	No	External	No
POSIX shell	No	No	No	No	Yes	No	No	Yes	Yes	No	Yes (Template:Mono)Script error: No such module "Check for unknown parameters".	No	No	No	No	Yes	No	External	No
bash (v4.0)	Yes	Yes	Yes	Yes^{[nb 9]}	Yes	No	No	Yes	Yes	No	Yes (Template:Mono, Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	optional	No	No	No	Yes	Yes	External	No
csh	Yes	Yes	No	No	Yes	No	No	Yes	Yes	No	Yes (Template:Mono, Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	optional	No	No	No	Yes	No	External	No
tcsh	Yes	Yes	when defined	No	Yes	No	No	Yes	Yes	No	Yes (Template:Mono, Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	optional	Yes	No	No	Yes	No	External	No
Hamilton C shell	Yes	Yes	No	Yes	Yes	No	No	Yes	Yes	No	Yes (Template:Mono, Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	No	No	No	No	Yes	No	External	No
Scsh	No	No	No	No	No	No	No	?	?	No	No	No	No	No	No	Yes	No	External	No
ksh (ksh93t+)	Yes (extendable)Script error: No such module "Check for unknown parameters".	Yes (extendable)Script error: No such module "Check for unknown parameters".	No	No	Yes	No	No	Yes	Yes	No	Yes (Template:Mono builtin, Template:Mono, Template:Mono implemented as functions)Script error: No such module "Check for unknown parameters".	No	No	No	No	Yes	Yes	External	No
pdksh	Yes	Yes	No	No	Yes	No	No	Yes	Yes	No	No	No	No	No	No	Yes	Yes	External	No
zsh	Yes	Yes	Yes	Yes^[25]	Yes	Yes^[26]	Yes (via Template:Mono or user-defined^[27])Script error: No such module "Check for unknown parameters".	Yes	Yes	Third-party extension^[28]	Yes	optional	Yes	No	when defined (as ZLE widgets)	Yes	Yes	External	Yes
ash	No	No	No	No	Yes	No	No	Yes	Yes	No	No	No	No	No	No	Yes	Yes	External	No
CCP	No	No	No	No	No	No	No	No	No	No	No	No	No	No	No	No	No	No	No
COMMAND.COM	No	No	No	No	No^{[nb 10]}^{[nb 11]}	No	No	No	No (only in DR-DOS through %$ON%, %$OFF%, %$HEADER%, %$FOOTER%)	No	No	No	No	No (only single-stepping with COMMAND /Y^[29])	No	No	No (only via external Template:Mono command, in DR-DOS also via Template:Mono / Template:Mono internal commands)	No	No
OS/2 CMD.EXE	Yes	Yes	No	No	Yes	No	No	No	No	No	No	No	No	No	No	No	No	No	No
Windows CMD.EXE	partial	partial	No	No	Yes (Template:Mono)Script error: No such module "Check for unknown parameters".	No	No	No	No	No	Yes (Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	No	No	No	No	Yes (via Template:Mono command)	No	No	No
4DOS	Yes	Yes	Yes	Yes	Yes^{[nb 12]}^{[nb 13]}	No	No	Yes	No	No	(via popup, extended directory searches, Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono commands and Template:Mono function)	Yes	No	Yes	No	Yes (via Template:Mono, Template:Mono and Template:Mono commands)	Yes (via Template:Mono function, and indirectly via a combination of Template:Mono, Template:Mono, Template:Mono commands)	No	Yes
4OS2	?	?	?	?	Yes	No	No	Yes	No	No	Yes	Yes	No	?	No	?	?	No	Yes
TCC (formerly 4NT)	Yes	Yes	Yes	Yes	Yes	No	No	Yes	No	Yes	(via popup, extended directory searches, Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono commands and Template:Mono function)	Yes	No	Yes	No	Yes (via Template:Mono, Template:Mono, Template:Mono and Template:Mono commands)	Yes (via Template:Mono function, and indirectly via a combination of Template:Mono, Template:Mono, Template:Mono commands)^{[nb 14]}	No	Yes
PowerShell	Yes	Yes	Yes	Yes	Yes (Template:Mono)Script error: No such module "Check for unknown parameters".	Yes	Yes; via PSReadLine^[30] module (bundled in v5.0^[31]) or in ISE^[32]	Third-party extension^[33]	Yes^[34]	Yes; via PSReadLine^[30] module (bundled in v5.0) or in ISE^[32]	Yes (multiple stacks; multiple location types;^[35] Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	Yes, in PSReadLine^[30] module	Yes, in ISE^[32]	Yes, in ISE^[32]	Yes	Yes^[36]	Yes^[37]	Yes, in ISE^[32]	popup window^[38]
rc	Yes^{[nb 15]}	Yes^{[nb 15]}	No	No	Yes^{[nb 15]}	No	No	No	?	No	No	No	No	No	No	?	No	No	No
BeanShell	Yes	Yes	No	No	No	No	No	?	?	No	No	No	No	No	No	No	No	No	No
VMS DCL	Minimum uniqueness scheme	No	No	No	Yes	Yes	No	?	?	No	No	No	No	No	No	Yes	No	No	No
fish	Yes	Yes	Yes^[39]	Yes^[39]	Yes	No	Yes	Yes	Yes (built-in helper available^[40])Script error: No such module "Check for unknown parameters".	Yes	Yes	Yes	Yes	Yes^{[nb 16]}	Yes, using Template:Mono command	Yes	(via Template:Mono command^[41])	No	No
Shell	Command name completion	Path completion	Command argument completion	Wildcard completion	Command history	Mandatory argument prompt	Automatic suggestions	Colored directory listings	Text highlighting	Syntax highlighting	Directory history, stack or similar features	Implicit directory change	Autocorrection	Integrated environment	Snippets	Value prompt	Menu/options prompt	Progress indicator	Context sensitive help

Background execution

Background execution allows a shell to run a command without user interaction in the terminal, freeing the command line for additional work with the shell. POSIX shells and other Unix shells allow background execution by using the & character at the end of command.

Completions

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File:Command-line-completion-example.gif

Command-line completion in Bash.

Completion features assist the user in typing commands at the command line, by looking for and suggesting matching words for incomplete ones. Completion is generally requested by pressing the completion key (often the Template:Keypress key).

Command name completion is the completion of the name of a command. In most shells, a command can be a program in the command path (usually $PATH), a builtin command, a function or alias.

Path completion is the completion of the path to a file, relative or absolute.

Wildcard completion is a generalization of path completion, where an expression matches any number of files, using any supported syntax for file matching.

Variable completion is the completion of the name of a variable name (environment variable or shell variable). Bash, zsh, and fish have completion for all variable names. PowerShell has completions for environment variable names, shell variable names and — from within user-defined functions — parameter names.

Command argument completion is the completion of a specific command's arguments. There are two types of arguments, named and positional: Named arguments, often called options, are identified by their name or letter preceding a value, whereas positional arguments consist only of the value. Some shells allow completion of argument names, but few support completing values.

Bash, zsh and fish offer parameter name completion through a definition external to the command, distributed in a separate completion definition file. For command parameter name/value completions, these shells assume path/filename completion if no completion is defined for the command. Completion can be set up to dynamically suggest completions by calling a shell function.^[42] The fish shell additionally supports parsing of man pages to extract parameter information that can be used to improve completions/suggestions. In PowerShell, all types of commands (cmdlets, functions, script files) inherently expose data about the names, types and valid value ranges/lists for each argument. This metadata is used by PowerShell to automatically support argument name and value completion for built-in commands/functions, user-defined commands/functions as well as for script files. Individual cmdlets can also define dynamic completion of argument values where the completion values are computed dynamically on the running system.

Command history

Template:Main article Users of a shell may find themselves typing something similar to what they have typed before. Support for command history means that a user can recall a previous command into the command-line editor and edit it before issuing the potentially modified command.

Shells that support completion may also be able to directly complete the command from the command history given a partial/initial part of the previous command.

Most modern shells support command history. Shells which support command history in general also support completion from history rather than just recalling commands from the history. In addition to the plain command text, PowerShell also records execution start- and end time and execution status in the command history.

Mandatory argument prompt

Script error: No such module "labelled list hatnote". Mandatory arguments/parameters are arguments/parameters which must be assigned a value upon invocation of the command, function or script file. A shell that can determine ahead of invocation that there are missing mandatory values, can assist the interactive user by prompting for those values instead of letting the command fail. Having the shell prompt for missing values will allow the author of a script, command or function to mark a parameter as mandatory instead of creating script code to either prompt for the missing values (after determining that it is being run interactively) or fail with a message.

Automatic suggestions

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File:Powershell Intellisense example for the Get-Process cmdlet.gif

Command-line completion in PowerShell.

Shells featuring automatic suggestions display optional command-line completions as the user types. The PowerShell and fish shells natively support this feature; pressing the Template:Keypress key inserts the completion.

Implementations of this feature can differ between shells; for example, PowerShell^[43] and zsh^[44] use an external module to provide completions, and fish derives its completions from the user's command history.^[45]

Directory history, stack or similar features

Script error: No such module "labelled list hatnote". Shells may record a history of directories the user has been in and allow for fast switching to any recorded location. This is referred to as a "directory stack". The concept had been realized as early as 1978^[46] in the release of the C shell (csh).

Command line interpreters 4DOS and its graphical successor Take Command Console also feature a directory stack.

Implicit directory change

A directory name can be used directly as a command which implicitly changes the current location to the directory.

This must be distinguished from an unrelated load drive feature supported by Concurrent DOS, Multiuser DOS, System Manager and REAL/32, where the drive letter L: will be implicitly updated to point to the load path of a loaded application, thereby allowing applications to refer to files residing in their load directory under a standardized drive letter instead of under an absolute path.^[47]

Autocorrection

File:Zsh autocompletion and autocorrection demo.gif

Zsh autocompletion and autocorrection demo for a telnet program.

When a command line does not match a command or arguments directly, spell checking can automatically correct common typing mistakes (such as case sensitivity, missing letters). There are two approaches to this; the shell can either suggest probable corrections upon command invocation, or this can happen earlier as part of a completion or autosuggestion.

The tcsh and zsh shells feature optional spell checking/correction, upon command invocation.

Fish does the autocorrection upon completion and autosuggestion. The feature is therefore not in the way when typing out the whole command and pressing enter, whereas extensive use of the tab and right-arrow keys makes the shell mostly case insensitive.

The PSReadLine^[30] PowerShell module (which is shipped with version 5.0) provides the option to specify a CommandValidationHandler ScriptBlock which runs before submitting the command. This allows for custom correcting of commonly mistyped commands, and verification before actually running the command.

Progress indicator

A shell script (or job) can report progress of long running tasks to the interactive user.

Unix/Linux systems may offer other tools support using progress indicators from scripts or as standalone-commands, such as the program "pv".^[48] These are not integrated features of the shells, however.

Colored directory listings

JP Software command-line processors provide user-configurable colorization of file and directory names in directory listings based on their file extension and/or attributes through an optionally defined %COLORDIR% environment variable.

For the Unix/Linux shells, this is a feature of the Template:Mono command and the terminal.

Text highlighting

The command line processors in DOS Plus, Multiuser DOS, REAL/32 and in all versions of DR-DOS support a number of optional environment variables to define escape sequences allowing to control text highlighting, reversion or colorization for display or print purposes in commands like TYPE. All mentioned command line processors support %$ON% and %$OFF%. If defined, these sequences will be emitted before and after filenames. A typical sequence for %$ON% would be \033[1m in conjunction with ANSI.SYS, \033p for an ASCII terminal or \016 for an IBM or ESC/P printer. Likewise, typical sequences for %$OFF% would be \033[0m, \033q, \024, respectively. The variables %$HEADER% and %$FOOTER% are only supported by COMMAND.COM in DR-DOS 7.02 and higher to define sequences emitted before and after text blocks in order to control text highlighting, pagination or other formatting options.

For the Unix/Linux shells, this is a feature of the terminal.

Syntax highlighting

Template:Main article A defining feature of the fish shell is built-in syntax highlighting, As the user types, text is colored to represent whether the input is a valid command or not (the executable exists and the user has permissions to run it), and valid file paths are underlined.^[49]

An independent project offers syntax highlighting as an add-on to the Z Shell (zsh).^[50] This is not part of the shell, however.

PowerShell provides customizable syntax highlighting on the command line through the PSReadLine^[30] module. This module can be used with PowerShell v3.0+, and is bundled with v5.0 onwards. It is loaded by default in the command line host "powershell.exe" since v5.0.^[51]

Take Command Console (TCC) offers syntax highlighting in the integrated environment.

Context sensitive help

Template:Main article

4DOS, 4OS2, 4NT / Take Command Console and PowerShell (in PowerShell ISE) looks up context-sensitive help information when Template:Keypress is pressed.

Zsh provides various forms of configurable context-sensitive help as part of its Template:Mono widget, Template:Mono command, or in the completion of options for some commands.

The fish shell provides brief descriptions of a command's flags during tab completion.

Programming features

Template:Sort-under

Shell	Functions	Exception handling	Search & replace on variable substitutions	Template:Verth	Template:Verth	Math function library	Linear arrays or lists	Template:Verth	Template:Verth	Template:Verth	Pseudorandom number generation	Bytecode
Bourne shell 1977 version	No	Yes (via Template:Mono)	No	No	No	No	No	No	No	Yes	No	No
Bourne shell current version	Yes since SVR2	Yes (via Template:Mono)	No	Yes^{[nb 8]}	No	No	No	No	No	Yes	No	No
POSIX shell	Yes	Yes (via Template:Mono)	No	Yes	No	No	No	No	No	Yes	No	No
bash (v4.0)	Yes	Yes (via Template:Mono)	Yes (via Template:Mono} syntax)Script error: No such module "Check for unknown parameters".	Yes	No	No	Yes	Yes	No	Yes	Yes (Template:Mono) Script error: No such module "Check for unknown parameters".	No
csh	No	No	Yes (via Template:Mono syntax)Script error: No such module "Check for unknown parameters".	Yes	No	No	Yes	No	No	Yes	No	No
tcsh	Work in progress^[52]	No	Yes (via Template:Mono syntax)Script error: No such module "Check for unknown parameters".	Yes	No	No	Yes	No	No	Yes	No	No
Hamilton C shell	Yes	No	Yes (via Template:Mono syntax)Script error: No such module "Check for unknown parameters".	Yes	Yes	Yes	Yes	No	No	Yes	Yes (random utility)	No
Scsh	Yes	?	Yes (via string functions and regular expressions)Script error: No such module "Check for unknown parameters".	?	?	?	Yes	?	Yes	Yes	Yes (random-integer, random-real)Script error: No such module "Check for unknown parameters".	Yes (compiler is Scheme48 virtual machine, via Template:Mono)Script error: No such module "Check for unknown parameters".
ksh (ksh93t+)	Yes	Yes (via Template:Mono)	Yes (via Template:Mono} syntax and builtin commands)Script error: No such module "Check for unknown parameters".	Yes	Yes	Yes	Yes	Yes	No	Yes	Yes (Template:Mono)Script error: No such module "Check for unknown parameters".	Yes (compiler is called Template:Mono)Script error: No such module "Check for unknown parameters".
pdksh	Yes	Yes (via Template:Mono)	No	Yes	No	No	Yes	No	No	Yes	Yes (Template:Mono)Script error: No such module "Check for unknown parameters".	No
zsh	Yes	Yes	Yes (via Template:Mono} and Template:Mono} syntax)Script error: No such module "Check for unknown parameters".	Yes	Yes	Yes (Template:Mono module)Script error: No such module "Check for unknown parameters".	Yes	Yes	No	Yes	Yes (Template:Mono)Script error: No such module "Check for unknown parameters".	Yes (built-in Template:Mono command)Script error: No such module "Check for unknown parameters".
ash	Yes	Yes (via Template:Mono)	No	Yes (since 1992)^[53]Script error: No such module "Check for unknown parameters".	No	No	No	No	No	Yes	No	No
CCP	No	?	No	No	?	?	No	No	No	No	No	No
COMMAND.COM	No	Partial (only Auto-fail (via Template:Mono (or Template:Mono in some versions of DR-DOS))	No	No	No	No	No	No	No	No	No	No
OS/2 CMD.EXE	No	No	No	?	No	No	?	No	No	No	No	No
Windows CMD.EXE	Yes (via Template:Mono)Script error: No such module "Check for unknown parameters".	No	Yes (via Template:Mono syntax)Script error: No such module "Check for unknown parameters".	Yes (via Template:Mono)^[54]Script error: No such module "Check for unknown parameters".	No	No	Yes (via Template:Mono^[55])Script error: No such module "Check for unknown parameters".	No	No	No	Yes (Template:Mono)Script error: No such module "Check for unknown parameters".	No
4DOS	Yes	Yes (via Template:Mono command, optional Auto-fail via Template:Mono)Script error: No such module "Check for unknown parameters".	Yes (via Template:Mono function)Script error: No such module "Check for unknown parameters".	Yes (via Template:Mono)Script error: No such module "Check for unknown parameters".	?	?	Yes (via ranges, include lists, Template:Monofile lists and Template:Mono command)Script error: No such module "Check for unknown parameters".	No	No	Yes	Yes (Template:Mono function)Script error: No such module "Check for unknown parameters".	Yes (via Template:Mono command)Script error: No such module "Check for unknown parameters".
4OS2	?	?	?	?	?	?	?	?	No	Yes	Yes (Template:Mono function)	?
TCC (formerly 4NT)	Yes	Yes (via Template:Mono and various Template:Mono commands)Script error: No such module "Check for unknown parameters".	Yes (via Template:Mono function)Script error: No such module "Check for unknown parameters".	Yes (via Template:Mono)Script error: No such module "Check for unknown parameters".	?	?	Yes (via ranges, include lists, Template:Monofile lists and Template:Mono command)Script error: No such module "Check for unknown parameters".	?	No	Yes	Yes (Template:Mono function)	Yes (via Template:Mono command)
PowerShell	Yes	Yes (Try-Catch-Finally)	Yes (Template:Mono operator)Script error: No such module "Check for unknown parameters".	Yes	Yes	[Math] class^[56]	Yes	Yes	Yes^[57]	Yes	Yes	Yes, automatic
rc	Yes	Yes	No	Yes	?	?	Yes	?	No	Yes	No	No
BeanShell	Yes	Yes	?	Yes	?	?	Yes	Yes	No	Yes	Yes	Yes
VMS DCL	Yes	Yes	No	Yes	No	yes, for compiled programs	Yes	No	No	No	No	No
fish	Yes	Yes (via Template:Mono)	Yes, via Template:Mono builtin command^[58]	Yes	Yes	Yes	Yes	No	No	Yes	Yes (Template:Mono)Script error: No such module "Check for unknown parameters".	No

String processing and filename matching

Template:Sort-under

Shell	String processing	Alternation (Brace expansion)	Pattern matching (regular expressions built-in)	Pattern matching (filename globbing)	Globbing qualifiers (filename generation based on file attributes)	Recursive globbing (generating files from any level of subdirectories)
Bourne shell 1977 version	?	No	No	Yes (Template:Mono, Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	No	No
Bourne shell recent version	Partial (prefix and suffix stripping in variable expansion)	No	No	Yes (Template:Mono, Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	No	No
POSIX shell	Partial (prefix and suffix stripping in variable expansion)	No	No	Yes (Template:Mono, Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	No	No
bash (v4.0)	Partial (prefix and suffix stripping in variable expansion)	Yes	Yes	Yes (Template:Mono, Template:Mono, Template:Mono, Template:Mono})Script error: No such module "Check for unknown parameters".	No	Yes (Template:Mono)
csh	Yes (:s and other editing operators)Script error: No such module "Check for unknown parameters".	Yes	No	Yes	No	No
tcsh	Yes (:s and other editing operators)Script error: No such module "Check for unknown parameters".	Yes	Yes	Yes	No	No
Hamilton C shell	Yes (:s and other editing operators + substr, strlen, strindex, printf, reverse, upper, lower, concat and other builtin functions)Script error: No such module "Check for unknown parameters".	Yes	No	Yes	No	Yes (via indefinite directory Template:Mono wildcard^[59])Script error: No such module "Check for unknown parameters".
Scsh	?	?	Yes	Yes	No	No
ksh (ksh93t+)	Partial (prefix, suffix stripping and string replacement in variable expansion)	Yes^[60]	Yes	Yes (Template:Mono, Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	No	Yes (with Template:Mono, no following of symlinks)
pdksh	?	Yes^[60]	No	Yes	No	No
zsh	Yes (through variable processing: e.g. substring extraction, various transformations via parameter expansion)	Yes	Yes	Yes (Template:Mono, Template:Mono, Template:Mono, extended globbing^[61])Script error: No such module "Check for unknown parameters".	Yes	Yes (Template:Mono or Template:Mono to follow symlinks)
ash	?	?	No	Yes	No	No
CCP	No	No	No	No	No	No
COMMAND.COM	No	No	No	Yes (Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	No	No
OS/2 CMD.EXE	No	No	No	Yes (Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	Partial (only in Template:Mono command)	No
Windows CMD.EXE	Partial (only through Template:Mono and Template:Mono)	No	No^{[nb 17]}	Yes (Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	Partial (only in Template:Mono command)	Yes (via Template:Mono command, or, where available, indirectly via Template:Mono subdir option)
4DOS	Yes (through variable functions Template:Mono, extended environment variable processing, various string commands and Template:Mono and Template:Mono)	No	No	Yes (Template:Mono, Template:Mono, Template:Mono, extended wildcards, Template:Mono popup command)Script error: No such module "Check for unknown parameters".	Yes (via Template:Mono attribute and Template:Mono description options and Template:Mono size, Template:Mono time, Template:Mono date, and Template:Mono file exclusion ranges)	Yes (via Template:Mono command, or indirectly via Template:Mono command or, where available, Template:Mono subdir option)
4OS2	?	No	No	?	?	?
TCC (formerly 4NT)	Yes (through variable functions Template:Mono, extended environment variable processing, various string commands and Template:Mono and Template:Mono)	No	Yes	Yes (Template:Mono, Template:Mono, Template:Mono, extended wildcards, Template:Mono popup command)Script error: No such module "Check for unknown parameters".	Yes (via Template:Mono attribute and Template:Mono description options and Template:Mono size, Template:Mono time, Template:Mono date, Template:Mono owner, and Template:Mono file exclusion ranges)	Yes (via Template:Mono command, or indirectly via Template:Mono command or, where available, Template:Mono subdir option)
PowerShell	Yes (Concat/Substring/Insert/Remove/Replace, ToLower/ToUpper, Trim/TrimStart/TrimEnd, Compare, Contains/StartsWith/EndWith, Format, IndexOf/LastIndexOf, Pad/PadLeft/PadRight, Split/Join, regular expression functions and other .NET string functions)Script error: No such module "Check for unknown parameters".	Range operator for numbers^[62]	Yes (full regex support)^{[nb 18]}Script error: No such module "Check for unknown parameters".	Yes (Template:Mono, Template:Mono, Template:Mono)Script error: No such module "Check for unknown parameters".	?	?
rc	?	?	No	Yes	No	No
BeanShell	?	?	Yes	?	?	?
VMS DCL	Yes	No	No	Yes	No	Yes (via Template:Mono)
fish	Yes (builtin string function)Script error: No such module "Check for unknown parameters".	Yes	Yes (via builtin Template:Mono and Template:Mono functions)Script error: No such module "Check for unknown parameters".	Yes (Template:Mono, Template:Mono, Template:Mono})Script error: No such module "Check for unknown parameters".	No	Yes (Template:Mono)

Inter-process communication

Shell	Pipes	Command substitution	Process substitution	Subshells	TCP/UDP connections as streams	Keystroke stacking
Bourne shell	bytes concurrent	Yes	No	Yes	No	Template:N/A^{[nb 19]}
POSIX shell	bytes concurrent	Yes	No	Yes	No	Template:N/A^{[nb 19]}
bash (v4.0)	bytes concurrent	Yes	Yes (if system supports Template:Mono or named pipes)Script error: No such module "Check for unknown parameters".	Yes	Yes (client only)Script error: No such module "Check for unknown parameters".	Template:N/A^{[nb 19]}
csh	bytes concurrent	Yes	No	Yes	No	Template:N/A^{[nb 19]}
tcsh	bytes concurrent	Yes	No	Yes	No	Template:N/A^{[nb 19]}
Hamilton C shell	bytes concurrent	Yes	No	Yes	No	?
Scsh	text	?	?	?	Yes	Template:N/A^{[nb 19]}
ksh (ksh93t+)	bytes (may contain serialized objects if Template:Mono is used) concurrent	Yes (Template:Mono and Template:Mono})Script error: No such module "Check for unknown parameters".	Yes (if system supports Template:Mono)Script error: No such module "Check for unknown parameters".	Yes	Yes (and SCTP support, client only)Script error: No such module "Check for unknown parameters".	Template:N/A^{[nb 19]}
pdksh	bytes concurrent	Yes	No	Yes	No	Template:N/A^{[nb 19]}
zsh	bytes concurrent	Yes	Yes	Yes	Yes (client and server, but only TCP)Script error: No such module "Check for unknown parameters".	Template:N/A^{[nb 19]}
ash	bytes concurrent	Yes	No	Yes	No	Template:N/A^{[nb 19]}
CCP	No	No	No	No	No	No
COMMAND.COM	text sequential temporary files	No	No	Partial (only under DR-DOS multitasker via Template:Mono)	No	No
OS/2 CMD.EXE	text concurrent	No	No	?	No	No
Windows CMD.EXE	text concurrent	Yes (via Template:Mono command)Script error: No such module "Check for unknown parameters".	No	Yes (Backtick: Template:Mono in Template:Mono)Script error: No such module "Check for unknown parameters".	No	No
4DOS	text sequential temporary files	Yes (via Template:Mono command)Script error: No such module "Check for unknown parameters".	?	Partial (via Template:Mono and Template:Mono, or via Template:Mono, Template:Mono and Template:Mono and Template:Mono)	No	Yes (via Template:Mono and Template:Mono)^[63]
4OS2	text concurrent	?	?	?	No	Yes (via Template:Mono)
TCC (formerly 4NT)	text concurrent	Yes (via Template:Mono command)Script error: No such module "Check for unknown parameters".	?	Partial (via Template:Mono and Template:Mono)	Yes (via Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono, Template:Mono and Template:Mono, client only)	Yes (via Template:Mono)
PowerShell	objects concurrent	Yes	No	Yes	Yes	?
rc	text concurrent	Yes	Yes (via: Template:Mono} if system supports Template:Mono)Script error: No such module "Check for unknown parameters".	Yes	No	?
BeanShell	not supported	?	?	?	Yes	?
VMS DCL	text (via Template:Mono command)	Yes	No	Yes (spawn)Script error: No such module "Check for unknown parameters".	Yes (server TCP only)Script error: No such module "Check for unknown parameters".	No
fish	bytes concurrent	Yes (Template:Mono)	No (broken)^[64]	No	No	Template:N/A^{[nb 19]}

Keystroke stacking

In anticipation of what a given running application may accept as keyboard input, the user of the shell instructs the shell to generate a sequence of simulated keystrokes, which the application will interpret as a keyboard input from an interactive user. By sending keystroke sequences the user may be able to direct the application to perform actions that would be impossible to achieve through input redirection or would otherwise require an interactive user. For example, if an application acts on keystrokes, which cannot be redirected, distinguishes between normal and extended keys, flushes the queue before accepting new input on startup or under certain conditions, or because it does not read through standard input at all. Keystroke stacking typically also provides means to control the timing of simulated keys being sent or to delay new keys until the queue was flushed etc. It also allows to simulate keys which are not present on a keyboard (because the corresponding keys do not physically exist or because a different keyboard layout is being used) and therefore would be impossible to type by a user.

Security features

Template:Importance section Template:Sort-under

Shell	Secure (password) prompt	File/directory passwords	Execute permission	Restricted shell subset	Safe data subset
Bourne shell	via Template:Mono^{[nb 20]}	?	Template:N/A^{[nb 21]}	Yes	No
POSIX shell	via Template:Mono^{[nb 20]}	?	Template:N/A^{[nb 21]}	No	No
bash (v4.0)	Template:Mono	?	Template:N/A^{[nb 21]}	Yes	No
csh	via Template:Mono^{[nb 20]}	?	Template:N/A^{[nb 21]}	Yes	No
tcsh	via Template:Mono^{[nb 20]}	?	Template:N/A^{[nb 21]}	Yes	No
Hamilton C shell	No	No	No	No	No
Scsh	via Template:Mono^{[nb 20]}	?	Template:N/A^{[nb 21]}	No	No
ksh (ksh93t+)	via Template:Mono^{[nb 20]}	?	Template:N/A^{[nb 21]}	Yes	No
pdksh	via Template:Mono^{[nb 20]}	?	Template:N/A^{[nb 21]}	Yes	No
zsh	Template:Mono	?	Template:N/A^{[nb 21]}^{[nb 22]}	Yes	No
ash	via Template:Mono^{[nb 20]}	?	Template:N/A^{[nb 21]}	Yes	No
CCP	No	No	No	No	No
COMMAND.COM	Partial (only under DR-DOS, prompts for password if file/directory is protected)	Partial (only under DR-DOS via Template:Mono syntax)^{[nb 23]}	Partial (only under DR-DOS, if files are password-protected for read and/or execute permission)^{[nb 24]}	No	No
OS/2 CMD.EXE	No	No	No	No	No
Windows CMD.EXE	No	No	No	No	No
4DOS	Yes (via Template:Mono or Template:Mono)^{[nb 25]}	Partial (only under DR-DOS via Template:Mono syntax)^{[nb 23]}	Partial (only under DR-DOS, if files are password-protected for read and/or execute permission)^{[nb 24]}	No	No
4OS2	?	No	No	No	No
TCC (formerly 4NT)	Yes (via Template:Mono, Template:Mono or Template:Mono)^{[nb 25]}	No	No	No	No
PowerShell	Yes^{[nb 26]}	No	No^{[nb 27]}	Yes^{[nb 28]}	Yes^[65]
rc	via Template:Mono^{[nb 20]}	?	Template:N/A^{[nb 21]}	Yes^[66]	No
BeanShell	?	?	?	?	?
VMS DCL	Yes	No	Yes	Yes	No
fish	Template:Mono	?	Template:N/A^{[nb 21]}^{[nb 22]}	Yes (via Template:Mono)	?

Secure prompt

Some shell scripts need to query the user for sensitive information such as passwords, private digital keys, PIN codes or other confidential information. Sensitive input should not be echoed back to the screen/input device where it could be gleaned by unauthorized persons. Plaintext memory representation of sensitive information should also be avoided as it could allow the information to be compromised, e.g., through swap files, core dumps etc.^[67]

The shells bash, zsh and PowerShell offer this as a specific feature.^[68]^[69] Shells which do not offer this as a specific feature may still be able to turn off echoing through some other means. Shells executing on a Unix/Linux operating system can use the Template:Mono external command to switch off/on echoing of input characters.^[70] In addition to not echoing back the characters, PowerShell's -AsSecureString option also encrypts the input character-by-character during the input process, ensuring that the string is never represented unencrypted in memory where it could be compromised through memory dumps, scanning, transcription etc.

Execute permission

Some operating systems define an execute permission which can be granted to users/groups for a file when the file system itself supports it.

On Unix systems, the execute permission controls access to invoking the file as a program, and applies both to executables and scripts. As the permission is enforced in the program loader, no obligation is needed from the invoking program, nor the invoked program, in enforcing the execute permissionTemplate:Snd this also goes for shells and other interpreter programs. The behaviour is mandated by the POSIX C library that is used for interfacing with the kernel. POSIX specifies that the exec family of functions shall fail with EACCESS (permission denied) if the file denies execution permission (see Template:Man).

The execute permission only applies when the script is run directly. If a script is invoked as an argument to the interpreting shell, it will be executed regardless of whether the user holds the execute permission for that script.

Although Windows also specifies an execute permission, none of the Windows-specific shells block script execution if the permission has not been granted.

Restricted shell subset

Several shells can be started or be configured to start in a mode where only a limited set of commands and actions is available to the user. While not a security boundary (the command accessing a resource is blocked rather than the resource) this is nevertheless typically used to restrict users' actions before logging in.

A restricted mode is part of the POSIX specification for shells, and most of the Linux/Unix shells support such a mode where several of the built-in commands are disabled and only external commands from a certain directory can be invoked.^[71]^[72]

PowerShell supports restricted modes through session configuration files or session configurations. A session configuration file can define visible (available) cmdlets, aliases, functions, path providers and more.^[73]

Safe data subset

Scripts that invoke other scripts can be a security risk as they can potentially execute foreign code in the context of the user who launched the initial script. Scripts will usually be designed to exclusively include scripts from known safe locations; but in some instances, e.g. when offering the user a way to configure the environment or loading localized messages, the script may need to include other scripts/files.^[74] One way to address this risk is for the shell to offer a safe subset of commands which can be executed by an included script.

Notes

Template:Reflist

References

Template:Reflist

External links

Script error: No such module "citation/CS1".
Script error: No such module "citation/CS1".

Template:Unix shells

↑ A platform independent version based on the historical UNIX V7 original source code is available from Geoff Collyer
↑ A platform independent version based on the SVr4/Solaris source code is available from Jörg Schilling
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ As part of IEEE Std.1003.2-1992 (POSIX.2); integrated into IEEE Std.1003.1 with the 2001 revision.
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1"., "Bash now supports the \u and \U Unicode escape."
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "Citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ ^a ^b ksh93(1) man page
↑ ^a ^b Default shell in OpenBSD is ksh (pdksh).
↑ The zsh command line editor is fully configurable and can allow mouse support in various ways such as with Stéphane Chazelas's Template:Mono.
↑ zsh(1) man page and subpages
↑ zshbuiltins(1) man page
↑ Template:Cite mailing list
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ This applies only on reserved words and other syntactic features.
↑ e.g. via 3rd party such as zsh-autosuggestions
↑ zsh does not feature syntax highlighting, but a 3rd party project exists which offers this capability as an add-on: zsh-syntax-highlighting
↑ Cite error: Invalid <ref> tag; no text was provided for refs named Paul_1997_OD-A3
↑ ^a ^b ^c ^d ^e Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ ^a ^b ^c ^d ^e Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Push-Location (with alias pushd) and Pop-Location (with alias popd) allows multiple location types (directories of file systems, organizational units of Active Directory, nodes of Windows Registry etc) to be pushed onto and popped from location stacks.
↑ The $host.ui.PromptForChoice function allows for a menu-style prompt for choices. The prompt works from background jobs as well as from remote sessions, displaying the menu prompt on the console of the controlling session.
↑ The Template:Mono cmdlet writes a progress bar which can indicate percentage, remaining seconds etc. The progress bar messages work from background jobs or remote sessions in addition to interactive scripts, i.e. the progress bar is displayed on the console of the controlling session, not as part of the regular output.
↑ The Template:Mono cmdlet inspects the command definition and opens an interactive windows with a named input field for each parameter/switch
↑ ^a ^b Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Introduce 'function' built-in by Matheus Garcia
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ The .NET System.Math class defines mathematical functions that can be used through the shortcut Template:Mono, e.g. Template:Mono for the sinus function.[1]
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ ^a ^b Script error: No such module "citation/CS1".
↑ Zsh offers a variety of globbing options.
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".
↑ Script error: No such module "citation/CS1".

Cite error: <ref> tags exist for a group named "nb", but no corresponding <references group="nb"/> tag was found

[1] A platform independent version based on the historical UNIX V7 original source code is available from Geoff Collyer

[2] A platform independent version based on the SVr4/Solaris source code is available from Jörg Schilling

[3] Script error: No such module "citation/CS1".

[4] Script error: No such module "citation/CS1".

[7] Script error: No such module "citation/CS1".

[8] As part of IEEE Std.1003.2-1992 (POSIX.2); integrated into IEEE Std.1003.1 with the 2001 revision.

[9] Script error: No such module "citation/CS1".

[10] Script error: No such module "citation/CS1"., "Bash now supports the \u and \U Unicode escape."

[Greer-11] Script error: No such module "citation/CS1".

[12] Script error: No such module "citation/CS1".

[PCWeek-13] Script error: No such module "Citation/CS1".

[Gomes-14] Script error: No such module "citation/CS1".

[Harris-15] Script error: No such module "citation/CS1".

[ksh93-man-page-16] sh93(1) man page

[default_OpenBSD-17] Default shell in OpenBSD is ksh (pdksh).

[18] The zsh command line editor is fully configurable and can allow mouse support in various ways such as with Stéphane Chazelas's Template:Mono.

[19] zsh(1) man page and subpages

[20] zshbuiltins(1) man page

[21] Template:Cite mailing list

[22] Script error: No such module "citation/CS1".

[27] Script error: No such module "citation/CS1".

[29] Script error: No such module "citation/CS1".

[30] Script error: No such module "citation/CS1".

[31] Script error: No such module "citation/CS1".

[34] Script error: No such module "citation/CS1".

[35] This applies only on reserved words and other syntactic features.

[36] .g. via 3rd party such as zsh-autosuggestions

[37] zsh does not feature syntax highlighting, but a 3rd party project exists which offers this capability as an add-on: zsh-syntax-highlighting

[Paul_1997_OD-A3-40] Cite error: Invalid <ref> tag; no text was provided for refs named Paul_1997_OD-A3

[PSReadLine-44] Script error: No such module "citation/CS1".

[45] Script error: No such module "citation/CS1".

[powershell_ise-46] Script error: No such module "citation/CS1".

[47] Script error: No such module "citation/CS1".

[48] Script error: No such module "citation/CS1".

[49] Push-Location (with alias pushd) and Pop-Location (with alias popd) allows multiple location types (directories of file systems, organizational units of Active Directory, nodes of Windows Registry etc) to be pushed onto and popped from location stacks.

[50] The $host.ui.PromptForChoice function allows for a menu-style prompt for choices. The prompt works from background jobs as well as from remote sessions, displaying the menu prompt on the console of the controlling session.

[51] The Template:Mono cmdlet writes a progress bar which can indicate percentage, remaining seconds etc. The progress bar messages work from background jobs or remote sessions in addition to interactive scripts, i.e. the progress bar is displayed on the console of the controlling session, not as part of the regular output.

[52] The Template:Mono cmdlet inspects the command definition and opens an interactive windows with a named input field for each parameter/switch

[fishcompletion-54] Script error: No such module "citation/CS1".

[55] Script error: No such module "citation/CS1".

[57] Script error: No such module "citation/CS1".

[58] Script error: No such module "citation/CS1".

[59] Script error: No such module "citation/CS1".

[60] Script error: No such module "citation/CS1".

[61] Script error: No such module "citation/CS1".

[62] Script error: No such module "citation/CS1".

[DRI_1987_CDOS_User-63] Script error: No such module "citation/CS1".

[64] Script error: No such module "citation/CS1".

[65] Script error: No such module "citation/CS1".

[66] Script error: No such module "citation/CS1".

[67] Script error: No such module "citation/CS1".

[68] Introduce 'function' built-in by Matheus Garcia

[69] Script error: No such module "citation/CS1".

[70] Script error: No such module "citation/CS1".

[71] Script error: No such module "citation/CS1".

[72] The .NET System.Math class defines mathematical functions that can be used through the shortcut Template:Mono, e.g. Template:Mono for the sinus function.[1]

[73] Script error: No such module "citation/CS1".

[74] Script error: No such module "citation/CS1".

[75] Script error: No such module "citation/CS1".

[Apress-76] Script error: No such module "citation/CS1".

[extended_globbing-77] Zsh offers a variety of globbing options.

[79] Script error: No such module "citation/CS1".

[4DOS_8.00_HELP-82] Script error: No such module "citation/CS1".

[83] Script error: No such module "citation/CS1".

[93] Script error: No such module "citation/CS1".

[94] Script error: No such module "citation/CS1".

[encryptmemory-95] Script error: No such module "citation/CS1".

[96] Script error: No such module "citation/CS1".

[97] Script error: No such module "citation/CS1".

[98] Script error: No such module "citation/CS1".

[99] Script error: No such module "citation/CS1".

[100] Script error: No such module "citation/CS1".

[101] Script error: No such module "citation/CS1".

[102] Script error: No such module "citation/CS1".

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Comparison of command shells

Contents

General characteristics

Interactive features

Background execution

Completions

Command history

Mandatory argument prompt

Automatic suggestions

Directory history, stack or similar features

Implicit directory change

Autocorrection

Progress indicator

Colored directory listings

Text highlighting

Syntax highlighting

Context sensitive help

Programming features

String processing and filename matching

Inter-process communication

Keystroke stacking

Security features

Secure prompt

Execute permission

Restricted shell subset

Safe data subset

Notes

References

External links

Navigation menu

Comparison of command shells

General characteristics

Interactive features

Background execution

Completions

Command history

Mandatory argument prompt

Automatic suggestions

Directory history, stack or similar features

Implicit directory change

Autocorrection

Progress indicator

Colored directory listings

Text highlighting

Syntax highlighting

Context sensitive help

Programming features

String processing and filename matching

Inter-process communication

Keystroke stacking

Security features

Secure prompt

Execute permission

Restricted shell subset

Safe data subset

Notes

References

External links

Navigation menu

Search