Nodejs child process and SIGKILL

Question

I am looking for a way to kill all child processes spawned when my parent process die (including by receiving SIGKILL).

PM2 process manager seems to have the key, because sending a SIGKILL to pm2 Daemon causes all child processes to exit (on Linux platform).

So do you know how PM2 achieve this ? how can I reproduce this behavior ?

Thanks !

score 1 · Answer 1 · answered Jun 11 '19 at 08:36

1

'use strict'

const { fork } = require('child_process')

// fork a child process
const child = fork('new_process.js')

// when the main process exits, send the kill signal to the child process
process.on('exit', (code) => {
  console.log(`About to exit with code: ${code}`)
  child.kill(9)
})

Usefull docs

NodeJS - Child Process - kill()

NodeJS - Process - exit event

answered Jun 11 '19 at 08:36

Andrea Franchini

548
4
14

Thanks ! And if my parent process receives a SIGKILL, is there a way to kill child similarly ? – Teajo Jun 11 '19 at 09:28
You can specify `process.on('SIGKILL', () => { child.kill(); process.exit(); }) ` – Andrea Franchini Jun 11 '19 at 09:56
Other info on manageable signals [here](https://nodejs.org/api/process.html#process_signal_events) – Andrea Franchini Jun 11 '19 at 09:58
6

A process can't listen on SIGKILL event – Teajo Jun 11 '19 at 11:14
Interestinf info here https://stackoverflow.com/questions/30708801/node-js-child-processes-being-killed-when-parent-dies - seems that the child will die always with default settings – Andrea Franchini Jun 11 '19 at 13:56
Thanks for the link, I have tested multiple spawn configurations but unfortunately child remains alive when parent is killed with SIGKILL, so I think it is just impossible to achieve what I want – Teajo Jun 11 '19 at 15:12
Is surely possibile, but it depends on the software design and node version – Andrea Franchini Oct 27 '20 at 15:13

Nodejs child process and SIGKILL

1 Answers1