# Python程序Daemon化

python守护进程实现原理：

* 首先守护进程必须将自己与父进程分离开，所以在第一个 `os.fork()`操作完成后立即终结父进程
* 当子进程成为孤儿以后，就调用`os.setsid()`创建一个全新的进程会话，并将子进程设为会话的头领，也就是子进程设置为新的进程组的头领进程，并确保没有任何与之关联的控制终端。

## 参考

* [Python Cookbook：在UNIX上加载守护进程](https://www.amazon.cn/Python-Cookbook-%E4%B8%AD%E6%96%87%E7%89%88-%E7%BE%8E-%E5%A4%A7%E5%8D%AB%C2%B7%E6%AF%94%E6%96%AF%E5%88%A9-%E5%B8%83%E8%8E%B1%E6%81%A9%C2%B7K-%E7%90%BC%E6%96%AF-%E8%91%97/dp/B01N3T8KQS/ref=pd_sim_351_1?ie=UTF8\&psc=1\&refRID=Q3FTP4P4GWBXYVF96TWB)


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