如何使用Python关闭树莓派（含RPI3）上的程序？

Hey there! Let's walk through how to shut down your Magic Mirror app and even your Raspberry Pi (works for RPi 3 and most other models) using Python. Here's what you need to know:

一、关闭智能魔镜程序 #

Since Magic Mirror typically runs as a Node.js process, we can use the psutil library to locate and terminate it cleanly.

• First, install the psutil library if you haven't already:

  pip install psutil
  

• Python code to stop Magic Mirror:
  This script scans running processes, identifies the Magic Mirror Node.js instance, and tries to shut it down gracefully (with a fallback to force termination if needed):

  import psutil
  
  def stop_magic_mirror():
      # Loop through all active processes
      for proc in psutil.process_iter(['pid', 'name', 'cmdline']):
          try:
              # Check if it's a Node.js process tied to Magic Mirror
              # Adjust the 'MagicMirror' check to match your actual installation path if needed
              if proc.name() == 'node' and any('MagicMirror' in part for part in proc.cmdline()):
                  print(f"Found Magic Mirror process (PID: {proc.pid}) — shutting down...")
                  proc.terminate()  # Try graceful shutdown first
                  
                  # Wait a few seconds to confirm termination; force kill if stuck
                  try:
                      proc.wait(timeout=3)
                      print("Magic Mirror closed successfully!")
                  except psutil.TimeoutExpired:
                      proc.kill()
                      print("Force-closed Magic Mirror successfully.")
                  return
          except (psutil.NoSuchProcess, psutil.AccessDenied, psutil.ZombieProcess):
              continue
      print("No Magic Mirror process found running.")
  
  # Call the function to shut down the app
  stop_magic_mirror()
  

• If you use PM2 to manage Magic Mirror:
  You can skip psutil and call PM2 directly from Python:

  import subprocess
  
  def stop_magic_mirror_pm2():
      try:
          # Replace 'magicmirror' with your actual PM2 process name
          subprocess.run(['pm2', 'stop', 'magicmirror'], check=True)
          print("PM2-managed Magic Mirror has been shut down.")
      except subprocess.CalledProcessError:
          print("Failed to stop Magic Mirror via PM2 — check your process name or PM2 status.")
  
  stop_magic_mirror_pm2()
  

二、关闭树莓派系统 #

Once your Magic Mirror app is closed, you can also trigger a system shutdown directly from Python.

• Python code to shut down the Pi:

  import subprocess
  
  def shutdown_rpi():
      print("Shutting down Raspberry Pi...")
      try:
          # Execute the system shutdown command (requires sudo privileges)
          subprocess.run(['sudo', 'shutdown', '-h', 'now'], check=True)
      except subprocess.CalledProcessError:
          print("Shutdown failed — check if your script has sudo access.")
  
  # Combine app shutdown and system shutdown (optional)
  stop_magic_mirror()
  shutdown_rpi()
  

Important Notes: #

• To avoid entering a sudo password every time, edit the sudoers file:
  Run sudo visudo and add this line (replace pi with your username):

  pi ALL=(ALL) NOPASSWD: /sbin/shutdown
  

• For testing, use sudo shutdown -h +1 instead of now — this gives you 1 minute to cancel with sudo shutdown -c if something goes wrong.

内容的提问来源于stack exchange，提问作者Smith john