| #!/bin/bashset -utrap '[ ${#PIDS[@]} -gt 0 ] && kill -TERM ${PIDS[@]}' TERMdeclare -a PIDSfor port in $WEB_PORTS; do	echo starting a web server listening on port "$port";	/webserver.py "$port" &	PIDS+=($!)donewait "${PIDS[@]}"trap - TERMwait "${PIDS[@]}"
 |