How to Pass Arguments to a Bash Script in 2025

With Bash scripting remaining a powerful tool in 2025, knowing how to pass arguments to your scripts is a foundational skill every developer and system administrator should master.

This guide is designed to help you pass arguments effectively, enabling dynamic script executions and reducing redundancy in your scripts.

Introduction

Passing arguments to a Bash script allows you to direct what the script will process. It can make your scripts more versatile and useful, as they can handle various input data and perform different actions without changing the code. In this article, we will explore the methods for passing arguments to a Bash script.

Understanding Script Arguments

In a Bash script, arguments passed from the command line are accessible using special positional variables. These variables are defined as follows:

• $0: The name of the script itself.
• $1, $2, ..., $N: The first, second, ..., Nth command-line argument.
• $@: All the arguments supplied to the script.
• $#: The number of arguments passed to the script.

Passing Arguments to a Bash Script

To pass arguments to your Bash script, simply provide them after the script name in the command line. Here's a basic example:

#!/bin/bash

echo "Script name: $0"
echo "First argument: $1"
echo "Second argument: $2"
echo "All arguments: $@"
echo "Number of arguments: $#"

Running the Script

Save the script above to a file, for example, example.sh. Give it executable permission and run it:

chmod +x example.sh
./example.sh arg1 arg2 arg3

Output:

Script name: ./example.sh
First argument: arg1
Second argument: arg2
All arguments: arg1 arg2 arg3
Number of arguments: 3

Handling Edge Cases

Checking Argument Pattern

Sometimes, you'll need to check if an argument starts with a specific pattern. This can be particularly useful for handling flags or options in your script. Check out this guide on checking argument patterns in bash for more information.

Quoting and Escaping Arguments

When passing arguments containing spaces or special characters, ensure they are properly quoted. Improper quoting can lead to unexpected behavior. For insights on handling quotes effectively, see this article on formatting quotes.

Processing Multiple Arguments

To handle multiple arguments, consider using a loop to iterate through them. This approach can help manage scripts where the input number and order of arguments may vary:

#!/bin/bash

for arg in "$@"
do
   echo "Argument: $arg"
done

Capturing Bash Output

Sometimes, your script needs to interact with external systems or tools, capturing output efficiently. For example, capturing Bash script output over SSH is a common requirement. Learn about capturing Bash output over SSH via Paramiko for advanced scenarios.

Conclusion

Passing arguments to a Bash script is a fundamental aspect that adds flexibility and power to your scripts. Whether you're handling simple values, checking patterns, or managing complex quoting and output scenarios, mastering this skill will enhance how you automate and manage tasks with Bash. As you develop your scripts in 2025, leverage these techniques to create adaptable, efficient, and reliable scripts.