How do you run multiple programs in parallel from a bash script?

Question

I am trying to write a .sh file that runs many programs simultaneously

I tried this

prog1 
prog2

Answer 1

You can use wait:

some_command &
P1=$!
other_command &
P2=$!
wait $P1 $P2

It assigns the background program PIDs to variables ($! is the last launched process' PID), then the wait command waits for them. It is nice because if you kill the script, it kills the processes too!