Day 98: Python OS Module

Today you’ll learn about the os module in Python — a built-in module that lets you interact with the operating system, making it very useful in automation and DevOps scripting.

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🧠 What is the os Module?

The os module provides a way to:

• Work with environment variables

• Handle file and directory paths

• Execute system commands

• Manage processes

This is especially useful in DevOps tasks like:

• Creating automation scripts for deployment

• Reading system info (like environment variables)

• Creating/deleting directories for builds

• Executing shell commands in CI/CD pipelines

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⚙️ Commonly Used Functions

📂 Working with Directories

import os

# Get current working directory
print(os.getcwd())

# List files in current directory
print(os.listdir())

# Create a new directory
os.mkdir("build_dir")

# Remove a directory
os.rmdir("build_dir")

# Change directory
os.chdir("..")

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⚡ Running System Commands

import os

# Run a system command
exit_code = os.system("echo Hello DevOps!")
print("Command exit code:", exit_code)

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🌍 Environment Variables

import os

# Access environment variables
print(os.environ)

# Get a specific variable
print(os.environ.get("HOME"))

# Set a new variable
os.environ["STAGE"] = "production"

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💡 Use Cases in DevOps

• Creating directory structures for builds or deployments

• Reading credentials from environment variables

• Executing shell commands during build scripts

• Cleaning up logs or temp directories automatically