DEV Community: Marcio Mendes

Linux: Essential Commands for Software Engineers

Marcio Mendes — Tue, 28 Jan 2025 03:34:02 +0000

Introduction

Hey everyone, how’s it going?

In this article, I’ll cover some simple yet incredibly impactfull Linux commands that every software engineer should know.

Mastering the Linux command line is crucial for developers of all experience levels. The terminal gives you full control over your environment, enabling automation, process management, file handling, and much more.

So, here’s a guide showcasing the most important commands every programmer should know to boost productivity.

Let’s dive in!

1. File and Directory Management

ls – List files and directories with details:

ls -l    # Displays file details, like permissions and ownership
ls -la   # Displays all files, including hidden ones
ls -lh   # Shows file sizes in human-readable format
ls -ltr  # Lists files sorted by modification date

cd – Navigate directories:

cd /path/to/directory  # Access a specific directory
cd ..                 # Move up one directory
cd -                  # Return to the previous directory

pwd – Display the absolute path of the current directory:

pwd

mkdir – Create new directories:

mkdir new_directory
mkdir -p folder1/folder2  # Create nested directories

rm – Remove files and directories:

rm file.txt          # Remove a file
rm -r directory/     # Remove a directory and its contents
rm -f file.txt       # Remove a file without confirmation

2. Everyday Useful Commands

touch – Create empty files or update modification dates:

touch file.txt                    # Create an empty file
touch -t 202401010101 file.txt    # Set modification date to Jan 1, 2024

find – Search for files and directories:

find /home -name "*.txt"         # Find .txt files in /home
find . -type d -name "projects"  # Find directories named "projects"

locate – Quickly find files by name:

locate file.txt

df – Show disk usage:

df -h  # Display disk usage in a readable format

du – Display file and directory sizes:

du -sh folder/  # Show the total size of a directory

3. Reading and Manipulating Text Files

cat – Display file content:

cat file.txt

less – Navigate large files efficiently:

less file.txt

grep – Search and filter patterns in files:

grep "term" file.txt          # Return lines containing "term"
grep -i "term" file.txt       # Ignore case differences
grep -r "error" /var/log/    # Recursively search directories

awk – Process and extract text columns:

awk '{print $1}' file.txt                 # Display the first word of each line
awk -F: '{print $1, $3}' /etc/passwd      # Show user and UID from a password file

sed – Programmatically edit files:

sed 's/old_word/new_word/g' file.txt  # Replace all occurrences in a file
sed -n '2,4p' file.txt                # Show only lines 2 to 4

4. Process Management

ps – List running processes:

ps aux

top / htop – Monitor CPU and memory usage in real-time:

top

kill – Terminate processes by ID:

kill -9 1234  # End process with PID 1234

5. Executing Files and Package Management

Running scripts directly:

./script.sh

Running scripts with a specific interpreter:

bash script.sh
python3 script.py

Making HTTP requests with curl:

curl -X POST -H "Content-Type: application/json" -d '{"key":"value"}' https://api.example.com

Package management with dpkg (Debian-based distros):

dpkg -i package.deb  # Install a package
dpkg -r package      # Remove a package
dpkg -l | grep name  # List installed packages filtered by name

6. User and Permissions Management

Users and superusers:

whoami   # Display the current user
sudo su  # Switch to superuser (root)

Managing permissions:

chmod 755 script.sh  # Grant execution permission to owner and read to others
ls -l script.sh      # Show file permissions as rwxr-xr-x

Using symbols to set permissions:

chmod u+x script.sh       # Add execution permission for owner
chmod go-r file.txt       # Remove read permission for group and others
chmod u+w file.txt        # Add write permission for owner
chmod a+r file.txt        # Grant read permission to everyone

Using numbers to set permissions:

chmod 755 script.sh  # Owner: read/write/execute (7), Group/Others: read/execute (5)
chmod 644 file.txt   # Owner: read/write (6), Group/Others: read (4)
chmod 777 script.sh  # Full permissions for everyone

7. Managing Compressed Files and File Transfers

Creating and handling compressed files:

tar -cvf archive.tar file1.txt file2.txt     # Create a tar archive
tar -czvf archive.tar.gz file1.txt file2.txt  # Create a gzip-compressed tar file
tar -xvf archive.tar                         # Extract tar files
tar -xzvf archive.tar.gz                     # Extract tar.gz files

Compressing and decompressing with gzip and gunzip:

gzip file.txt       # Compress file.txt to file.txt.gz
gunzip file.txt.gz  # Decompress file.txt.gz

Unzipping .zip files:

unzip file.zip                  # Extract the contents of file.zip
unzip file.zip -d /path/to/dir  # Extract to a specific directory
unzip -l file.zip               # List files in a zip archive

Connecting to a remote server with ssh:

ssh user@server.com                # Connect to a remote server
ssh -p 2222 user@server.com        # Connect using a specific port
ssh user@server.com 'ls -l /path'  # Run a command on the remote server

8. Using Aliases to Boost Productivity

Creating an alias:

alias ll='ls -lh'       # Create an alias for detailed and readable file listing
alias gs='git status'   # Create an alias for "git status"

Making aliases permanent:

nano ~/.bashrc  # For Bash
nano ~/.zshrc   # For Zsh
alias ll='ls -lh'  # Add your alias to the file
source ~/.bashrc   # Apply changes for Bash
source ~/.zshrc    # Apply changes for Zsh

Conclusion

Thanks for read this Article, I hope you found this guide helpful.

Feel free to suggest other essential commands, and let’s keep learning together.

By the way, if you're interested, check out my other article:
GitHub Repositories Every Software Engineer Should Know.

It's packed with resources to level up your skills!

Thanks again, and see you in the next one!

References

GitHub Repositories Every Software Engineer Should Know

Marcio Mendes — Sun, 30 Jun 2024 18:17:18 +0000

Finally, after a long time, I am realizing my desire to write articles to help other software engineers advance their careers. With this, I intend to help them improve their knowledge while allowing myself to learn and grow during the process.

In my first article, I present to you a compilation of interesting repositories for all software engineers who seek to stay updated and improve their skills whenever possible, regardless of their level or position.

Let's get straight to it, organized by categories:

RoadMaps
Books, Blogs, and Websites
Algorithms
Design Patterns
System Design
Design Resources
Projects, Tutorials, and APIs
Interviews

RoadMaps

In the RoadMaps category, we have two repositories that provide a pathway to follow when you are looking to learn about a language or tool, giving you a direction on the basic knowledge you should acquire or already have.

kamranahmedse / developer-roadmap

Interactive roadmaps, guides and other educational content to help developers grow in their careers.

roadmap.sh

Community driven roadmaps, articles and resources for developers

Roadmaps are now interactive, you can click the nodes to read more about the topics.

View all Roadmaps · Best Practices · Questions

Here is the list of available roadmaps with more being actively worked upon.

Have a look at the get started page that might help you pick up a path.

Creational Design Patterns	Structural Design Patterns	Behavioral Design Patterns
Simple Factory	Adapter	Chain of Responsibility
Factory Method	Bridge	Command
Abstract Factory	Composite	Iterator
Builder	Decorator	Mediator
Prototype	Facade	Memento
Singleton	Flyweight	Observer
Proxy	Visitor
Strategy
State
Template Method

Website	Description
SVG sine waves	Export perfect sine waves as SVG for your front-end projects
UI Design Daily	Awesome UI Components of all types
100 Daily UI

API	Description	Call this API
IP Stack	Locate and Identify Website Visitors by IP Address
Marketstack	Free, easy-to-use REST API interface delivering worldwide stock market data in JSON format
Weatherstack	Retrieve instant, accurate weather information for any location in the world in lightweight JSON format
Numverify	Global Phone Number Validation & Lookup JSON API
Fixer	Fixer is a simple and lightweight API for current and historical foreign exchange (forex) rates.

DEV Community: Marcio Mendes

Linux: Essential Commands for Software Engineers

Introduction

1. File and Directory Management

2. Everyday Useful Commands

3. Reading and Manipulating Text Files

4. Process Management

5. Executing Files and Package Management

6. User and Permissions Management

7. Managing Compressed Files and File Transfers

8. Using Aliases to Boost Productivity

Conclusion

References

GitHub Repositories Every Software Engineer Should Know

RoadMaps

kamranahmedse / developer-roadmap

Interactive roadmaps, guides and other educational content to help developers grow in their careers.

roadmap.sh

View all Roadmaps · Best Practices · Questions

liuchong / awesome-roadmaps

A curated list of roadmaps.

Awesome Roadmaps

Contents

Programming Language

Books, Blogs, and Websites

EbookFoundation / free-programming-books

📚 Freely available programming books

List of Free Learning Resources In Many Languages

Intro

How To Contribute

kilimchoi / engineering-blogs

A curated list of engineering blogs

Software Engineering Blogs

Companies

Individuals/Group Contributors

Products/Technologies

Companies

# companies

A companies

B companies

sdmg15 / Best-websites-a-programmer-should-visit

🔗 Some useful websites for programmers.

Best-websites-a-programmer-should-visit

📖 Index

freeCodeCamp / freeCodeCamp

freeCodeCamp.org's open-source codebase and curriculum. Learn to code for free.

freeCodeCamp.org's open-source codebase and curriculum

Table of Contents

Certifications

Algorithms

The Algorithms · GitHub

arpit20adlakha / Data-Structure-Algorithms-LLD-HLD

A Data Structure Algorithms Low Level Design and High Level Design collection of resources.

Data-Structure-Algorithms-LLD-HLD

Data Structure Resources

Theory with Practice Problems

For Readers

For Video Enthusiasts

Places to Find Interview Experiences

Compensation Related Information

Solving Practice Problems

tayllan / awesome-algorithms

A curated list of awesome places to learn and/or practice algorithms.

Awesome Algorithms

Websites

Design Patterns

kamranahmedse / design-patterns-for-humans

An ultra-simplified explanation to design patterns

Introduction

DovAmir / awesome-design-patterns

A curated list of software and architecture related design patterns.

Awesome Software and Architectural Design Patterns

Contents

Programming Language Design Patterns

System Design

ByteByteGoHq / system-design-101

Explain complex systems using visuals and simple terms. Help you prepare for system design interviews.

System Design 101

Table of Contents

donnemartin / system-design-primer

Please read `contributing guidelines` before submitting new resources.