Bash run processes in parallel and exit with status code example

parallel.sh

#!/bin/bash

set -eux

declare -a arr=("backend" "frontend")

FAIL=0

for i in "${arr[@]}"
do
  pkgpath="$(pwd)/packages/$i"
  echo "Building $pkgpath"
  (cd $pkgpath && npm run lint) &
done

for job in `jobs -p`
do
echo $job
  wait $job || let "FAIL+=1"
done

if [ "$FAIL" == "0" ];
then
  echo "Complete."
  exit 0
else
  echo "Completed with errors."
  exit 1
fi