runsvinit/README.md

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# runsvinit
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If you have a Docker container that's a collection of runit-supervised daemons,
this process is suitable for use as the ENTRYPOINT.
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See [the example](https://github.com/peterbourgon/runsvinit/tree/master/example).
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**Why not just exec runsvdir?**
`docker stop` issues SIGTERM (or, in a future version of Docker, perhaps another custom signal)
but if runsvdir receives a signal,
it doesn't wait for its supervised processes to exit before returning.
If you don't care about graceful shutdown of your daemons, no problem, you don't need this tool.
**Why not wrap runsvdir in a simple shell script?**
This works great:
```sh
#!/bin/sh
sv_stop() {
for s in $(ls -d /etc/service/*)
do
/sbin/sv stop $s
done
}
trap "sv_stop; exit" SIGTERM
/sbin/runsvdir /etc/service &
wait
```
...except it doesn't [reap orphaned child processes](https://blog.phusion.nl/2015/01/20/docker-and-the-pid-1-zombie-reaping-problem/)
and is therefore unsuitable for being PID 1.
**Why not use my_init from phusion/baseimage-docker?**
That works great — if you're willing to add python3 to your Docker images :)
**So this is just a stripped-down my_init in Go?**
Basically, yes.