Ben Warai Otoko

CLI Tricks & Power User Commands

3 min read

Summary

Essential command-line tricks, shortcuts, and productivity enhancers for working efficiently in the terminal. These techniques help reduce typing, improve workflow speed, and leverage the full power of the shell.

Key concepts

  • History manipulation: Quickly recall and reuse previous commands
  • Keyboard shortcuts: Navigate and edit command lines efficiently
  • Piping and redirection: Chain commands and control output flow
  • Process management: Control running processes and background jobs
  • Text processing: Manipulate text streams with built-in tools

Details

History manipulation

Command history navigation:

  • !! - Repeat last command
  • !$ - Last argument of previous command
  • !* - All arguments of previous command
  • !n - Execute command number n from history
  • !string - Execute most recent command starting with “string”
  • ^old^new - Replace “old” with “new” in previous command

History search:

  • Ctrl+R - Reverse search through command history
  • Ctrl+R again - Cycle through matches
  • history | grep keyword - Search command history

Keyboard shortcuts

Navigation:

  • Ctrl+A - Jump to beginning of line
  • Ctrl+E - Jump to end of line
  • Ctrl+U - Clear line before cursor
  • Ctrl+K - Clear line after cursor
  • Alt+B - Move back one word
  • Alt+F - Move forward one word

Editing:

  • Ctrl+W - Delete word before cursor
  • Alt+D - Delete word after cursor
  • Ctrl+Y - Paste previously deleted text
  • Ctrl+L - Clear screen (same as clear)
  • Ctrl+C - Cancel current command
  • Ctrl+Z - Suspend current process

Piping and redirection

Output control:

  • command > file.txt - Redirect output, overwrite file
  • command >> file.txt - Redirect output, append to file
  • command 2> error.log - Redirect stderr only
  • command &> all.log - Redirect both stdout and stderr
  • command 2>&1 - Redirect stderr to stdout

Piping:

  • cmd1 | cmd2 - Pipe output of cmd1 to input of cmd2
  • cmd1 | tee file.txt - Show output and save to file
  • cmd1 && cmd2 - Run cmd2 only if cmd1 succeeds
  • cmd1 || cmd2 - Run cmd2 only if cmd1 fails
  • cmd1; cmd2 - Run both commands sequentially

Process management

Background jobs:

  • command & - Run command in background
  • jobs - List background jobs
  • fg %n - Bring job n to foreground
  • bg %n - Resume job n in background
  • disown %n - Detach job from current shell

Process control:

  • ps aux | grep process_name - Find process by name
  • pgrep process_name - Get PID by process name
  • pkill process_name - Kill process by name
  • kill -9 PID - Force kill process
  • top or htop - Interactive process viewer

Text processing

Quick text manipulation:

  • grep pattern file - Search for pattern in file
  • sed 's/old/new/g' file - Replace text in file
  • awk '{print $1}' file - Print first column
  • cut -d',' -f1 file.csv - Extract first field from CSV
  • sort file | uniq - Sort and remove duplicates
  • wc -l file - Count lines in file

Examples

Navigate to previous directory:

cd -

Create directory and enter it:

mkdir new-project && cd $_

Download file and show progress:

wget -c URL  # or
curl -O URL

Find and replace in multiple files:

grep -rl "old_text" . | xargs sed -i 's/old_text/new_text/g'

Monitor log file in real-time:

tail -f /var/log/syslog

Disk usage of directories, sorted:

du -h --max-depth=1 | sort -hr

Find large files:

find / -type f -size +100M 2>/dev/null

Extract, transform, load pattern:

cat data.txt | grep "ERROR" | awk '{print $3}' | sort | uniq -c

Quick backup of file before editing:

cp config.yml{,.backup}
# Creates config.yml.backup

Run command with timeout:

timeout 10s command

Resources

Graph View

Backlinks

Recent Notes