Thank you for your suggestion. I incorporated your suggestion by commenting this out... so that there is only one waitpid in the whole script. 
foreach (@all_kids) {
    waitpid ($_, 0);
}

[download]
And using the REAPER subroutine that you gave. But now two things came up. Under normal condition (without pressing ctrl-c), the parent script exits without 'waiting for the children to finish'.

And when I try to put a 'sleep 20' and the end of the main script, this is the output that I am getting. 
Process 1 exited.
Process 1 exited.

[download]

In reply to Re^2: Monitoring Child Process by Anonymous Monk
in thread Monitoring Child Process by Anonymous Monk

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