ncdu: The Lazy Admin’s Disk-Space Detective

ncdu (NCurses Disk Usage) is a command-line tool that turns disk-space sleuthing into a breeze.

ncdu 是一款命令行下的磁盘分析工具，使用交互界面，查询系统中的大文件。

Installation

sudo apt install ncdu        # Debian/Ubuntu
sudo yum install ncdu        # CentOS/RHEL
brew install ncdu            # macOS (via Homebrew)

Basic usage

1. Scan your system:

   ncdu /                  # Scan root (use sudo for system directories)
   ncdu ~/Downloads        # Target a specific folder
   

2. Navigate:

3. ↑/↓: Move between items.
4. Enter: Open a directory.
5. ←: Go back.
6. d: Delete selected file/dir (double-check before hitting this!).

7. ?: Toggle help menu.

8. Quit: Press q or Ctrl+C.

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Pro tips

• Limit scan depth to save time:

  ncdu --max-depth=3 /   # Scan only 3 subdirectory levels
  

• Exclude folders (e.g., external drives):

  ncdu --exclude /mnt /
  

• Export/Reload results:

  ncdu -o scan_result.txt /path   # Save scan
  ncdu -f scan_result.txt         # Reopen later