Shell
A shell is Article description::a command-line interpreter that offers a text-based interface to users. It can be used as command-line interface (CLI) on a terminal emulator or as a script interpreter running in the background.
Typically the shell is the first program started after a user logs in at a terminal. The /etc/passwd file contains information on the default shell for each user on the system.
Available software
| Name | Package | Homepage | Description |
|---|---|---|---|
| bash | app-shells/bash | https://tiswww.case.edu/php/chet/bash/bashtop.html | The Bourne Again Shell, is the default shell on Gentoo. It is used by Portage, Gentoo's default package manager. |
| dash | app-shells/dash | http://gondor.apana.org.au/~herbert/dash/ | The Debian Almquist Shell, a small, fast, and posix-compliant shell suited for startup scripts (as /bin/sh replacement). |
| fish | app-shells/fish | https://fishshell.com/ | The Friendly Interactive SHell. |
| ksh | app-shells/ksh | http://www.kornshell.com/ | The Original Korn Shell, 1993 revision (ksh93). |
| mksh | app-shells/mksh | https://www.mirbsd.org/mksh.htm | An actively developed free implementation of the Korn Shell, and well suited for scripting. |
| tcsh | app-shells/tcsh | http://www.tcsh.org/ | an enhanced version of the Berkeley C Shell (csh). |
| xonsh | dev-python/xonsh | http://xon.sh/ | A Python-based shell that falls back to bash commands. |
| zsh | app-shells/zsh | http://www.zsh.org/ | An advanced shell that is the chosen interactive shell for many users. |
Many shell scripts reference the /bin/sh file; this is generally a symlink to the shell of choice.
For more shell options see the output of the following command (app-portage/eix required):
user $eix -cC app-shellsConfiguration
Changing the default system shell
System administrators can change the default system shell using the eselect utility.
If it is not installed, emerge the app-eselect/eselect-sh package:
root #emerge --ask app-eselect/eselect-shTo list possible shell options use:
root #eselect sh listTo set dash as the default system shell:
root #eselect sh set dashChanging a user's shell
The default shell for users can be changed on an individual basis using the chsh command. To change the default shell for the current user, type chsh and enter a correct path to the new shell. In the example below, a user named Larry the cow (Larry) is changing his default shell from /bin/bash to /bin/dash:
user $chshChanging the login shell for larry Enter the new value, or press ENTER for the default Login Shell [/bin/bash]: /bin/dash
chsh can be used by the super user account to change the default shell for any user.