How to kill all subprocesses of shell?

Question

I'm writing bash script, which does several thing.

In the beginning it starts several monitor scripts, each of them runs some other tools.

At the end of my main script, I would like to kill all things that spawned from my shell.

So, it might looks like this:

#!/bin/bash

some_monitor1.sh &
some_monitor2.sh &
some_monitor3.sh &

do_some_work
...

kill_subprocesses

The thing is that most of these monitors spawn their own subprocesses, so doing (for example): killall some_monitor1.sh will not always help.

Any other way to handle this situation?

Answer 1

After starting each child process, you can get its id with

ID=$!

Then you can use the stored PIDs to find and kill all grandchild etc. processes as described here or here.

Answer 2

kill $(jobs -p)

Answer 3

If you use a negative PID with kill it will kill a process group.

Answer 4

pkill with optioin "-P" should help:

pkill -P $(pgrep some_monitor1.sh)

from man page:

   -P ppid,...
          Only match processes whose parent process ID is listed.

There are some discussions on linuxquests.org, please check:

http://www.linuxquestions.org/questions/programming-9/use-only-one-kill-to-kill-father-and-child-processes-665753/