Please explain: trap 'sudo kill -9 -- -$$' EXIT
bash, command, shell, unix
Solution
- `$$` is the process ID of the script itself
- `-$$` means use the process group ID
- `--` signals the end of options
So upon exit the `trap` will kill all subprocesses of the script.
§ Internal Variables
Problem
What is this shell command doing? ``` trap 'sudo kill -9 -- -$$' EXIT ```