Package Managers & Software Management

Your terminal (apt install git)
        ↓
Local package index (knows what's available)
        ↓
Download from Ubuntu/Debian repository servers
        ↓
Verify signature (prevents tampered packages)
        ↓
Extract files to correct system locations
        ↓
Register package in local database

sudo apt update

# Install a single package
sudo apt install git

# Install multiple packages at once
sudo apt install git python3 python3-pip cmake ninja-build

# Install without confirmation prompt
sudo apt install -y build-essential gcc g++ make

# Typical embedded development setup in one command
sudo apt install -y \
  git \
  cmake \
  ninja-build \
  python3 \
  python3-pip \
  python3-venv \
  build-essential \
  gcc \
  libusb-1.0-0-dev \
  openocd \
  gdb-multiarch \
  minicom \
  screen

apt search cmake              # Search by keyword
apt show cmake                # Detailed info about a package
apt list --installed          # List all installed packages
apt list --installed | grep python   # Filter installed packages

sudo apt upgrade              # Upgrade all packages to their latest version
sudo apt full-upgrade         # Upgrade with dependency changes (more aggressive)
sudo apt dist-upgrade         # Distribution upgrade — adds/removes packages as needed

sudo apt remove git           # Remove the program (keep config files)
sudo apt purge git            # Remove program AND its config files
sudo apt autoremove           # Remove packages that were installed as dependencies
                              # but are no longer needed
sudo apt clean                # Delete downloaded .deb files from cache
sudo apt autoclean            # Delete only outdated cached .deb files

# Example: Add a newer version of GCC
sudo add-apt-repository ppa:ubuntu-toolchain-r/test
sudo apt update
sudo apt install gcc-13 g++-13

# Example: Add Node.js repository
curl -fsSL https://deb.nodesource.com/setup_20.x | sudo -E bash -
sudo apt install nodejs

# Remove a PPA
sudo add-apt-repository --remove ppa:ubuntu-toolchain-r/test

# Install a package
pip install numpy

# Install a specific version
pip install tensorflow==2.15.0

# Install from a requirements file
pip install -r requirements.txt

# List installed packages
pip list

# Show detailed info about a package
pip show numpy

# Upgrade a package
pip install --upgrade numpy

# Uninstall a package
pip uninstall numpy

# Search (deprecated in newer pip — use pypi.org instead)
pip install esptool            # ESP32 flashing tool
pip install pyserial           # Serial communication
pip install scikit-learn pandas matplotlib

# Create a virtual environment in the current directory
python3 -m venv .venv

# Activate it
source .venv/bin/activate       # Linux / macOS
# .venv\Scripts\activate        # Windows PowerShell

# Your prompt changes to show the active env:
# (.venv) rajath@ubuntu:~/projects$

# Install packages inside the env (no sudo needed)
pip install numpy pandas scikit-learn

# Save all installed packages to a file
pip freeze > requirements.txt

# Install from requirements on another machine
pip install -r requirements.txt

# Deactivate when done
deactivate

# Search for a snap package
snap find code

# Install Visual Studio Code (the professional way on Ubuntu)
sudo snap install code --classic

# Install other tools
sudo snap install arduino                 # Arduino IDE
sudo snap install cmake --classic

# List installed snaps
snap list

# Remove a snap
sudo snap remove code

# Check snap service status
snap services

# Install a downloaded .deb file
sudo dpkg -i package_name.deb

# Fix broken dependencies after dpkg install
sudo apt install -f

# List all installed packages
dpkg -l

# Check if a specific package is installed
dpkg -l | grep cmake

# Show files installed by a package
dpkg -L cmake

# Show which package owns a file
dpkg -S /usr/bin/gcc

# 1. Download source code
git clone https://github.com/someproject/tool.git
cd tool

# 2. Check dependencies (read the README!)
sudo apt install -y libssl-dev libffi-dev

# 3. Configure — generates a Makefile for your system
./configure --prefix=/usr/local

# 4. Build (use -j$(nproc) to use all CPU cores)
make -j$(nproc)

# 5. Install system-wide
sudo make install

# 6. Verify
which tool
tool --version

# Download a file
wget https://example.com/tool-v1.0.tar.gz

# Download and show progress
wget -c https://example.com/large_file.iso   # -c = resume if interrupted

# Run an install script directly (verify the source first!)
curl -fsSL https://get.docker.com | sudo sh

# Download a file with curl
curl -o filename.tar.gz https://example.com/file.tar.gz

# Fetch a URL and print output to terminal
curl https://api.example.com/status

# Extract .tar.gz
tar -xzf archive.tar.gz

# Extract .tar.xz
tar -xJf archive.tar.xz

# Extract to a specific directory
tar -xzf archive.tar.gz -C /opt/

# List archive contents without extracting
tar -tzf archive.tar.gz

# Create an archive
tar -czf my_project.tar.gz ./my_project/

# Core development tools
sudo apt install -y git build-essential gcc g++ make cmake ninja-build pkg-config

# Python ecosystem
sudo apt install -y python3 python3-pip python3-venv python3-dev

# Serial communication and flashing
sudo apt install -y minicom screen picocom
pip install esptool pyserial

# Debugging
sudo apt install -y gdb gdb-multiarch openocd

# USB and device management
sudo apt install -y libusb-1.0-0 libusb-1.0-0-dev usbutils

# Version control
sudo apt install -y git git-lfs

# Compression
sudo apt install -y unzip p7zip-full

# System monitoring
sudo apt install -y htop iotop nethogs