Bash trap exit kill last process -

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i have following in bash file: (i kill web server once bash script on under circumstances)

python -m simplehttpserver 12345 & trap "kill $!" exit

i wondering how safe/widespread this? when $! evaluated (i pretty sure happens @ place of declaration, still need advice)?

what wrote safe. because you're using double quotes, $! evaluated immediately. if used single quotes evaluated @ time script exits.


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