how to wait on multiple background processes and check exit status in bash

wait.sh

#!/bin/bash

FAIL=0

echo "starting"

./sleeper 2 0 &
./sleeper 2 1 &
./sleeper 3 0 &
./sleeper 2 0 &

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

echo $FAIL

if [ "$FAIL" == "0" ];
then
    echo "YAY!"
else
    echo "FAIL! ($FAIL)"
fi

but how could you know the first subprocess in loop is the one finished first, if the later ones in loop finished early, what is the return code

that's a nice workaround.. but, using just the wait command (without passing the process ID) would have worked too? So that, it waits for all the background process to get complete.

./sleeper 2 0 &
./sleeper 2 1 &
./sleeper 3 0 &
./sleeper 2 0 &

wait

Please let me know your thoughts.

(I got here from your blog post - http://jeremy.zawodny.com/blog/archives/010717.html)

So nice, thank you! It works in my script.