LAS/start.py

#!/usr/bin/env python3
import subprocess
import os
import sys

PRO_PATH = "/platform/LAS/"
LOGFILE = PRO_PATH + "LAS.log"
PIDFILE = PRO_PATH + "LAS.pid"

def is_running(pid):
    try:
        os.kill(pid, 0)
        return True
    except OSError:
        return False

def start():
    if os.path.exists(PIDFILE):
        with open(PIDFILE, "r") as f:
            pid = int(f.read())
            if is_running(pid):
                print(f"LAS is already running with PID {pid}")
                return
            else:
                print("Found stale PID file. Cleaning up.")
                os.remove(PIDFILE)

    with open(LOGFILE, "a") as log:
        process = subprocess.Popen(
            [sys.executable, "LAS.py"],
            stdout=log,
            stderr=log,
            stdin=subprocess.DEVNULL,
            close_fds=True,
        )
        with open(PIDFILE, "w") as f:
            f.write(str(process.pid))
        print(f"LAS started with PID {process.pid}")

if __name__ == "__main__":
    start()