bash: manage background tasks and terminate them all on Ctrl+C

Run multiple background tasks in bash and gather every task exit code:

declare -A process
declare -A result

for host in $hosts; do

ssh -o ConnectTimeout=10 "$host" /bin/task &
process["$host"]=$!

done

# Get results
for host in $hosts; do
    wait ${process["$host"]}
    result["$host"]=$?
    [ ${result["$host"]} -eq 0 ] && echo "OK: $host" || echo "ERROR: $host"
done

Yes, you can use associative arrays in bash >= 4.0.

Terminate all background tasks if main script was interrupted by Ctrl+C:

function term_all_processes() {
	echo "Sending SIGTERM to all background jobs..."
	for proc in $(jobs -lp); do
		echo "PID $proc"
		kill -15 $proc
	done
	exit 1
}
trap term_all_processes SIGINT

Bash has trap built-in that allows to create custom handlers for recieved signals. Ctrl+C actually is terminal escape sequence that generates SIGINT.

License: