Bash Shell

old bash shell page (fr)

Types

There exist multiple different types of shells in Linux :

• Bourne Shell (sh)
• C Shell (csh or tcsh)
• Korn Shell (ksh)
• Z Shell (zsh)
• Bourne Again Shell (bash)

All of them serve a common purpose, which is to facilitate communication between the user and the operating system.

To check the shell being used, we have to use the following command:

marijan$ echo $SHELL

/bin/bash

Bash is probably the most popular shell because of these features.

It's possible to change the default shell using the following command :

marijan$ chsh

Enter the new value, or press enter for the default
         Login Shell [/bin/bash]: /bin/sh

Features

Bash has multiple interesting features that make him the most used type of shell. Here is some examples :

• Auto-Completion : When you are typing a command, you don't really need to type in the entire command. Indeed, you can type the beginning of the command or the name of your file or folder, and then press tab to auto-complete. Here is a example with the command ls :

marijan$ ls Docu [PRESS TAB] Documents

• Alias : You can create an alias if you would like to save time or if it's easier for you to remember some commands. For instance, here we have created an alias for the date command :

marijan$ alias dt=date
marijan$ dt
Thu 21 Mar 2024 04:09:44 PM CET

• History : We can view the history of commands by using the following command :

marijan$ History
ls Documents
alias dt=date
dt