“How To Create Shell Script In Linux: A Beginner’s Guide”

How To Create Shell Script In Linux: A Beginner’s Guide

Linux shell scripting deals with creating and processing the script. The main purpose of shell scripting is to systemize systems. Are you a beginner or an experienced user? Let’s learn about how to create a shell script that can manage your time and make it easier for you. In this guide, let’s learn step-by-step how to write, save, and run a shell script in Linux.

WHAT IS SHELL IN LINUX

 A shell script is a simple text file that contains a series of commands written for Linux scripting, like bash, sh, and zsh. Instead of just typing every command manually, you can save the command in a script and run it all at once, like you would run a command for a program. This helps you to work faster and easier, especially for regular tasks such as file management, system monitoring, software installation, or backups.

 COMPARISON OF POPULAR LINUXS

Comparison of popular Linux shells like bash, Zsh, Fish, Ksh, and Tcsh. Let me brief the command scripting. Bash is a user-friendly shell with great scripting, like cron. Zhs has features like input completion, modules, and user-friendly; it’s popular among developers. Fish is a modern and user-friendly tool that highlights easily. Ksh is a powerful command-line tool mostly used for advanced scripting and also supports older shells. Tcsh is well known to C programmers because it has a C-like syntax.

Shell	Full Form of shell / Meaning	Main Features	Best use
Bash	Bourne Again	Linux systems, great for scripting,	Beginners & scripting
Zsh	Z Shell	Input completion, modules, and user-friendly	Developers & power users
Fish	Friendly Interactive	Modern design, syntax highlighting, suggestions	New users who want ease of use
Ksh	Korn	Strong scripting capabilities, supports older shells	Advanced scripting & legacy systems
Tcsh	TENEX C	C-like syntax, users familiar with C programming	Programmers are used to C syntax

EXECUTE SHELL SCRIPT IN LINUX

Now, let’s start with creating and running a shell script in Linux. In this guide, we’ll learn how to create a workspace, the step-by-step procedure for creating the first script. For Windows, you can use Linux distros like Ubuntu, WSL, or other distros. Here are some basic terminal keys, like (cd, ls, mkdir), and text editors, like nano, VS Code, or nano.

STEP 1: CREATE A FOLDER

First, if you are using Ubuntu desktop or WSL (Windows Subsystem for Linux), just open the terminal ( Ctrl+Alt+T) to create a file.

Create a folder called script in your home directory with the command

[ mkdir -p ~/scripts]. In this [-p] is an option to create a parent folder if it is needed. Then the command moves inside the folder and creates a new file. Use the command [pwd] to make the document folder, and run it, check with the [ls] command to see the new folder.

STEP 2: CREATE A NEW FILE

As we know, some text editors that are mentioned above, like nano, VS Code. For example, let’s use nano because it’s simple.

you can give a name to the script like [myscript.sh]. Click Enter, it creates a new file.

[.sh] is recommended for Linux, it can be known as it’s a script file. You can use other editors like vi, vim, or gedit

STEP 3: ADD THE SHEBANG LINES

Let’s know about shebang, it is the first line in a script; it is a standard shell. Without the lines, Linux may not identify which command-line to use.

This is the shebang line; it tells Linux to use bash to execute the commands in your script.

[#!]  are the shebang symbol and [ /bin/bash] is the interpreter of Linux, that used to run the script.

STEP 4: Write your own command

After the shebang line, try a welcome command that you want to run in the script.

Using the echo command helps to print in the script; it is also interactive and user-friendly. you need to save the file and exit it.

• Press Ctrl + O, then Enter to save.
• Press Ctrl + X to exit.

By clicking exit, it moves back to the terminal

STEP 5: Let’s execute the script

For executing the script, use the command [chomd].

[chomd] is a command that changes file permissions, by adding +x file can be executed.

[chmod] stands for change mode; it’s a Linux command that is used to set file and folder permissions.

STEP 6: Run the script

After executing the script, let’s run the command

The command for running the script is [./myscript sh].

[./] By using this explicitly without a file name, you may get an error.

Run the command by pressing “ENTER”.

It gives your script that you have created, then use [ls] to verify that the folder was created successfully.

TROUBLESHOOT FOR BEGINNERS

Some common problems that you can face from the beginning to the end of this guide, as a beginner. let’s start with some common errors that you can come across.

• Check the application menu for any sort of trouble in the terminal or commands.
• Install nano if the file won’t save or nano is not found.
• Check every command manually in a terminal before using it in shell scripting.

CONCLUSION

Shell scripting is not a tool in Linux; it is a strong tool that takes control of your system. The art of command-line scripting lies in flexibility, which can easily start with very basic commands and adding variables and loops to make your scripts. So, get ready and open the terminal, write your first script today!

FAQ

1. What is a shell script?

A shell script is a text file that contains a series of commands. Instead of typing commands one by one, you can run them all at once in a script.

2. Why should I use shell scripts?

Shell scripts are used to manage time, automate regular tasks, install system management, and reduce human errors.

3. Do I need programming knowledge to write command-line scripts?

 No, you can just start with basic Linux commands like variables, conditions, and loops.

4. What are some common uses of shell scripts?

These common uses are automating backups, monitoring system performance, installing software, scheduling tasks, managing files and directories.

5. Which shell should I use?

Linux systems mostly use bash as a default Unix , but you can also explore other user-friendly shells like Zsh, Ksh.