The shell is an interface that helps users to operate the system through different commands, scripts, and utilities provided by Linux and Unix-based operating systems. Shell is the most common way to interact with the system either they are local systems or headless servers.
When comparing Windows command-line with the shell, the Linux shell is more powerful and flexible with the complete set of tools. We can set up multiple shells and switch between the shells when we need to.
Here at LinuxAPT, as part of our Server Management Services, we regularly help our Customers to perform related Linux Shells queries.
In this context, we shall look into the best open-source shells which are maintained along with their own syntax and scripting features in Linux and Unix-based distro.
Shell Scripting is an open-source computer program designed to be run by the Unix/Linux shell. Shell Scripting is a program to write a series of commands for the shell to execute. It can combine lengthy and repetitive sequences of commands into a single and simple script that can be stored and executed anytime which, reduces programming efforts.
1. Bash Shell
Bash shell refers to Bourne Again Shell which can be found as default shell in most of the Linux distro. Bash shell is the most preferable and popular shell that is a replacement and improved version of Bourne Shell(sh). Bash shell supports command line editing which lets you edit the current command line as well as the command in your history list. It provides many features like unlimited array size index which lets you keep the history with no limit, job control mechanism for managing cron jobs, perform integer arithmetic of any base from two to sixty-four, etc. Bash also provides auto-completion support for paths, wildcards and command lines, etc.
To know more about what Bash shell can do, simply run the below Bash Shell Help command:
$ bash --help2. Zsh Shell
Zsh is the advanced and modern-day Linux shell that provides interactive and unique robust features and offers an interactive login shell. Zsh is also known for Z Shell and during zsh shell development it includes many improved features of shells such as bash, ksh, tcsh, etc. It provides a highly functional auto-complete for the file and paths along with an immense command history sharing mechanism. Spelling correction, smart escaping, recursive globbing, smart escaping, and many more interactive features are included in the zsh shell. Users can customize the shell using the community-driven framework oh-my-zsh which features more than 200 themes as well as more than 400 plugins.
To know more about Zsh Shell, Run the Zsh Shell Help command:
$ zsh --help3. Tcsh Shell
Tcsh refers to Tenex C Shell which is an extended version and backward-compatible version of the C shell which is used as an interactive login shell and shell script command processor. Tcsh provides many features like configurable command-line completion, job control, a modernized history mechanism, spellcheck support, a command-line editor, etc. Its syntax is quite similar to c programming so without bash knowledge, the script can be programmed.
Tcsh Shell Help command will show you more about Tcsh Shell:
$ tcsh --help4. Ksh Shell
Ksh refers to Korn Shell that was initially developed by David Korn including many features of C Shell and backward-compatible with Bourne shell. The ksh shell supports different features like floating-point arithmetic, command aliasing, job control, and many more features. Ksh shell allows the user to run jobs either in the background using the bg command or in the foreground using the fg command and terminate the current jobs using the ctrl + z key combo. It provides advanced I/O features alongside notable security mechanisms.
This article covers the most popular shells among Linux users. In fact, Shell is an environment in which we can run our commands, programs, and shell scripts. There are different flavors of a shell, just as there are different flavors of operating systems. Each flavor of shell has its own set of recognized commands and functions. As Linux is flexible we can switch between shells easily without any additional configuration.
What is a Shell Prompt in Linux ?
The prompt, $, which is called the command prompt, is issued by the shell. While the prompt is displayed, you can type a command.
Shell reads your input after you press Enter. It determines the command you want executed by looking at the first word of your input. A word is an unbroken set of characters. Spaces and tabs separate words.
Following is a simple example of the date command, which displays the current date and time:
$date
Thu Jun 25 08:30:19 MST 2021Functions of Linux kernel:
