Bash FOR loop with batched concurrency

loop.sh

#!/bin/bash

# https://unix.stackexchange.com/questions/103920/parallelize-a-bash-for-loop

NAMES=($(cat names.csv))

BATCH_SIZE=4

for NAME in ${NAMES[@]}; do
  # Increment or reset our counter
  ((i = i % $BATCH_SIZE))
  
  # The 'wait' pauses until all background commands are done
  ((i++ == 0)) && wait

  # The '&' runs the command in background, non-blocking
  some-cmd --some-args &
done