Screenshot of a sample tcsh session

Unix shell based on and backward compatible with the C shell.

- Tcsh

34 related topics


Command-line interface

A command-line interpreter or command-line processor uses a command-line interface (CLI) to receive commands from a user in the form of lines of text.

Screenshot of a sample Bash session in GNOME Terminal 3, Fedora 15
Screenshot of Windows PowerShell 1.0, running on Windows Vista
A graphical user interface with icons and windows (GEM 1.1 Desktop)
Apple Computer's CommandShell in A/UX 3.0.1
GNU Octave's GUI with command-line interface
Bourne shell interaction on Version 7 Unix
Prompt of a BBC Micro after switch-on or hard reset
An MS-DOS command line, illustrating parsing into command and arguments
The end of the HELP command output from RT-11SJ displayed on a VT100
A Teletype Model 33 ASR teleprinter keyboard with punched tape reader and punch
DEC VT52 terminal

Examples of command-line interpreters include DEC's DIGITAL Command Language (DCL) in OpenVMS and RSX-11, the various Unix shells (sh, ksh, csh, tcsh, zsh, Bash, etc.), CP/M's CCP, DOS' COMMAND.COM, as well as the OS/2 and the Windows CMD.EXE programs, the latter groups being based heavily on DEC's RSX-11 and RSTS CLIs.

C shell

tcsh and sh side-by-side on a Mac OS X desktop
C Shell running on Windows Services for UNIX
64-bit Hamilton C shell on a Windows 7 desktop.

The C shell (csh or the improved version, tcsh) is a Unix shell created by Bill Joy while he was a graduate student at University of California, Berkeley in the late 1970s.

Unix shell

Command-line interpreter or shell that provides a command line user interface for Unix-like operating systems.

tcsh and sh shell windows on a Mac OS X Leopard desktop

On many systems, csh may be a symbolic link or hard link to TENEX C shell (tcsh), an improved version of Joy's original version.

Z shell

Unix shell that can be used as an interactive login shell and as a command interpreter for shell scripting.

Screenshot of a Zsh session
Screenshot of a Zsh session
Z shell's configuration utility for new users
Zsh with Agnoster theme running on Konsole terminal emulator
Oh My Zsh logo

Zsh is an extended Bourne shell with many improvements, including some features of Bash, ksh, and tcsh.

TENEX (operating system)

Operating system developed in 1969 by BBN for the PDP-10, which later formed the basis for Digital Equipment Corporation's TOPS-20 operating system.

BBN Pager, circa 1970

The command line completion and help live on in current CLIs like tcsh.

Command-line completion

Common feature of command-line interpreters, in which the program automatically fills in partially typed commands.

Example of command-line completion in Bash.
Example of command-line completion in PowerShell with Intellisense.

Tcsh offers default file, command, and variable name completion activated using . The 'complete' builtin command provides fully programmable completion. The source code comes with a 'complete.tcsh' file containing many examples of its completion syntax.


Free and open-source Unix-like operating system descended from the Berkeley Software Distribution , which was based on Research Unix.

FreeBSD 13.0 bootloader with ASCII art logo
FreeBSD 13.0 bootloader with ASCII art logo
FreeBSD 13.0 startup with console login prompt
PC-BSD version 10, the operating system that was later known as TrueOS

The default FreeBSD shell is the tcsh shell for root, and the Almquist shell (sh) for regular users.

MacOS Catalina

Sixteenth major release of macOS, Apple Inc.'s desktop operating system for Macintosh computers.

Screenshot of the macOS Catalina desktop in dark mode
Screenshot of the macOS Catalina desktop in dark mode

Bash continues to be available in macOS Catalina, along with other shells such as csh/tcsh and ksh.

List of programming languages by type

List of notable programming languages, grouped by type.

The source code for a simple computer program written in the C programming language. The gray lines are comments that help explain the program to humans in a natural language. When compiled and run, it will give the output "Hello, world!".

csh and tcsh (C-like shell from Bill Joy at UC Berkeley)

Cd (command)

Command-line shell command used to change the current working directory in various operating systems.

The cd command in an rc session running on Plan 9 from Bell Labs
A user's view of the file system in Unix-like systems begins with the home directory (often abbreviated to ~). From there, the tree can spread into more subdirectories and/or files.

This is the case in most of the Unix shells (Bourne shell, tcsh, bash, etc.), on Microsoft Windows NT/2000+ and Windows PowerShell on Windows 7+ and on DOS/ Microsoft Windows 3.x-9x/ME.