Overview of Shell Bash

Bash, or "Bourne Again SHell," is a popular command-line interpreter for Unix and Unix-like operating systems. It is essential for automating tasks, managing system processes, and executing scripts. For a comprehensive guide, visit the Bash Beginner's Guide.

Key Features of Bash:

Command Line Editing: Edit commands using Emacs or vi modes.
Job Control: Suspend and resume processes efficiently.
Shell Functions: Group commands using user-defined functions.
History: Keep a history of executed commands for easy reuse.

Basic Syntax

Bash commands can be executed directly in the terminal or saved in a script file. Here’s a simple example:

#!/bin/bash
    echo "Hello, Bash!"

Basic Bash Examples:

Here are some common examples of Bash commands:

1. Variables

name="Alice"
    echo "Name: $name"

2. Conditional Statements

age=20
    
    if [ $age -ge 18 ]; then
        echo "You are an adult."
    else
        echo "You are a minor."
    fi

Learn more about conditional statements in Bash at The Linux Documentation Project.

3. Loops

for i in {1..5}; do
        echo "Iteration: $i"
    done

For an in-depth look at loops, visit Shell Scripting Loops.

4. Functions

function greet {
        local name=$1
        echo "Hello, $name!"
    }
    
    greet "Alice"

Explore functions further with Shell Script Functions.

Common Bash Commands

Here are some frequently used Bash commands:

ls: Lists files and directories.
cd: Changes the current directory.
cp: Copies files and directories.
mv: Moves or renames files and directories.
rm: Removes files or directories.

For a comprehensive list of commands, refer to Codecademy Command Line Commands.

File Permissions

Bash allows you to manage file permissions using the chmod command:

chmod +x script.sh

Best Practices

Here are some best practices for writing Bash scripts:

Use set -e at the beginning to exit on errors.
Comment your code to explain complex logic.
Double-quote variable expansions to prevent word splitting.
Test scripts in a safe environment before production.

Learning Resources

Here are some great resources to learn Bash:

Input

Output