daemonize
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Why this lib doesnt fork twice?
Readed lots of posts, all mention we should fork twice for daemonize a py process, why this lib dont?
@penpen
I am wondering the same...
Double fork is a technique meant to re-parent the daemon process to init. Some investigations show that it does not change its parent, as opposed to what we usually imagine a "daemon" would do.
For example, if you run the usage section of the doc, you may see:
$ ps j $(cat /tmp/test.pid)
PPID PID PGID SID TTY TPGID STAT UID TIME COMMAND
2091 21109 21109 21109 ? -1 Ss 1000 0:00 python3 daemon.py
The number under PPID is the pid of the parent process. On my computer this is the pid of systemd daemon, not init:
$ ps 2091
PID TTY STAT TIME COMMAND
2091 ? Ss 0:00 /lib/systemd/systemd --user
Strictly saying, I don't say the package is "daemonizing" the process. But thinking that it makes my script running in background is acceptable to me.