Fundamental command-line commands (0)

By Hongyu Xiao
# NAVIGATION AND DIRECTORY MANAGEMENT
# Print Working Directory
pwd

# List directory contents
ls
ls -l        # Detailed list view
ls -a        # Show hidden files
ls -lh       # Human-readable file sizes

# Change Directory
cd /path/to/directory
cd ..        # Move up one directory
cd ~         # Go to home directory

# CREATE AND MANAGE FILES/DIRECTORIES
# Create directory
mkdir my_folder

# Create empty file
touch newfile.txt

# Remove file
rm file.txt

# Remove directory
rm -r directory_with_contents

# Copy files
cp source.txt destination.txt

# Move/Rename files
mv oldname.txt newname.txt
mv file.txt /path/to/directory/

# VIEW FILE CONTENTS
# Display file contents
cat filename.txt

# View file contents page by page
less filename.txt

# Show first/last lines
head filename.txt
tail filename.txt

# SYSTEM INFORMATION
# Current user
whoami

# System information
uname -a

# Disk space
df -h

# Memory usage
free -h

# PROCESS MANAGEMENT
# List running processes
ps aux

# Search for a process
ps aux | grep process_name

# PERMISSIONS
# Change file permissions
chmod 755 filename
# 755 means:
# 7 (owner): read, write, execute
# 5 (group): read, execute
# 5 (others): read, execute

# SEARCHING
# Find files
find /path -name "filename"

# Search file contents
grep "search_term" filename.txt

# COMPRESSED FILES
# Extract .tar.gz
tar -xzvf file.tar.gz

# Extract .zip
unzip file.zip

# Compress directory
tar -czvf archive.tar.gz directory_name

# COMMAND HELP
# Get help for a command
man command_name
command --help