Run multiple commands at once in the same terminal

This bash script is for N parallel threads. Each argument is a command.

trap will kill all subprocesses when SIGINT is catched.
wait $PID_LIST is waiting each process to complete.
When all processes have completed, the program exits.

#!/bin/bash

for cmd in "$@"; do {
  echo "Process \"$cmd\" started";
  $cmd & pid=$!
  PID_LIST+=" $pid";
} done

trap "kill $PID_LIST" SIGINT

echo "Parallel processes have started";

wait $PID_LIST

echo
echo "All processes have completed";

Save this script as parallel_commands and make it executable.
This is how to use this script:

parallel_commands "cmd arg0 arg1 arg2" "other_cmd arg0 arg2 arg3"

Example:

parallel_commands "sleep 1" "sleep 2" "sleep 3" "sleep 4"

Start 4 parallel sleep and waits until “sleep 4” finishes.

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