BASH Script to Get the Child Process IDs recursively.

#!/bin/bash
function return_child_pid
{
   pd=$1
   count=0
   for p in `ps -ef | awk '$3=="'"$pd"'" {print $2}'`;
   do
      count=$(($count+1))
      return_child_pid $p
   done
   if [ $count == 0 ]; then
     echo $1
     return $1
   fi
}

return_child_pid $1