Running a linux script to check on process and if stopped how to make it start the process

however, i was bored... something like:

#!/bin/sh

SUBJECT="blah is more than 5 minutes old!"
EMAIL="email@example.com"
MSG="/tmp/emailmessage"

MOD=`stat --printf=%Y $1`
NOW=`date +%s`
DIFF=$(($NOW-$MOD))
if [ $DIFF > 300 ]; then
    echo "$1 is more than 5 minutes old!" > $MSG
    mail -s "$SUBJECT" "$EMAIL" < $MSG
fi

Use the wait command.

This demo:

#!/bin/bash
echo $SECONDS
sleep 12&
sleep 15&
jobs
wait
echo $SECONDS
echo "jobs are done"

Produces this output:

0
[1]-  Running                 sleep 12 &
[2]+  Running                 sleep 15 &
15
jobs are done

There's a fifteen second pause before the last two lines are output.