How to Manage Child Process IDs in Bash Scripts?

Another approach is to use `$!` to capture the PID of each spawned process as you go and store them in an array. Then, you can loop through this array to kill any processes when needed.

If you're open to exploring, there's a command called `coproc` in bash that creates a piped process and gives you a list of PIDs. However, you'd need to handle the I/O since it involves pipes.

Consider adding an argument like `--id=12345` to your scripts and pass a different ID each time you run the main script. This way, when it comes time for cleanup, you can use `pgrep 'id=12345'` to identify the right processes. This method requires minimal changes to your scripts.

One way to manage this is to have each child process write its PID to a common file or communicate through a named pipe. Then you can use `pkill` with the signal option to terminate those processes collectively. Additionally, it might help to name your child processes with a unique identifier to facilitate targeted kills.

You might want to track the PIDs right when you spawn them. This way, you'll have a clear list of processes to clean up later on. If you're looking to persist this list, consider writing it to a file. While it's a bit clunky, it can be effective. Just be aware that if the processes become orphaned, the method of checking parent processes might not work. The suggested approach of utilizing `ps` can help if you can identify the processes reliably.