1.3Navigating the Filesystem

Basic Navigation Commands

# Print current directory
pwd

# List files (basic)
ls

# List files with details (permissions, size, date)
ls -la

# List files sorted by modification time (newest first)
ls -lt

# List files with human-readable sizes
ls -lh

# Change directory
cd /var/log
cd ..           # Go up one level
cd -            # Go to previous directory
cd ~/projects   # Go to projects in home directory

Finding Files

# Find a file by name (recursive search)
find / -name "playwright.config.ts" 2>/dev/null

# Find files modified in the last 24 hours
find /var/log -mtime -1 -type f

# Find files larger than 100MB (hunt for disk space issues)
find / -size +100M -type f 2>/dev/null

# Find all .spec.ts files in the project
find ~/projects/webapp -name "*.spec.ts" -type f

# Faster alternative: locate (uses a pre-built index)
locate playwright.config.ts

Disk Usage

# Disk usage summary
df -h

# Directory size
du -sh /var/log/

# Top 10 largest directories
du -h /var/log/ | sort -rh | head -10

# Check if disk is full (common cause of test failures)
df -h | grep -E "9[0-9]%|100%"