#!/bin/ksh

exposed_tcp_in=$(netstat -l -n -finet -ptcp |\
  awk '$4 !~ /^127\.0\.0\.1.*$/ && $1 == "tcp" {print $4}')

output=""
if [ ! -z "$exposed_tcp_in" ]; then 
    output=$output"[ "
    for i in $exposed_tcp_in; do
        port="${i##*.}"
        output="$output\"$port\","
    done
    output=${output%?}" ]"
fi
echo $output