re-use node.js process to

shell.sh

cm_env_exp() {

  rm -rf /tmp/srv-input
  mkfifo /tmp/srv-input

  rm -rf /tmp/srv-output
  mkfifo /tmp/srv-output

  (
   (
    tail -f /tmp/srv-input > >(node -e '
                const fd = fs.openSync("/tmp/srv-output", "w+");
                const s = fs.createWriteStream(null,{fd});
                // s.write("\n");
                process.stdin.resume().on("data", d => {
                    // console.log("d:", String(d));
                    const v = String(d).split("=");
                    if(v === "EOF"){
                       process.exit(0);
                    }
                    s.write(v.shift());
                    s.write(v.join(""));
                   // s.write("\n");
                });
              ') &
  )
  ) &> /dev/null

  node_pid="$!"

  (
#     sleep .15;
    (
      env | grep 'cm_' | grep -v 'BASH_FUNC' | grep -v 'cm_color' | while read line; do
        echo "$line" > /tmp/srv-input
      done;

      echo "EOF" > /tmp/srv-input

    ) &
   ) # &> /dev/null

  (
   export kill_this="$BASHPID"
   cat /tmp/srv-output | while read line; do
      if [[ "$line" == 'EOF' ]]; then
         kill -9 "$kill_this"
         exit 0;
      fi
       echo -e "$line"
    done;
  )
#  echo 'waiting'
#  tail -f /tmp/srv-output
}