File check_mail_queue of Package postfix

#!/bin/bash

nm()
{
    NM=$( /usr/bin/mailq 2> /dev/null | tail -1 | /usr/bin/gawk '{ print $5 }' )
    if [ "$NM" ]
    then
        return 0
    else
        return 1
    fi
}

test -e /var/run/check_mail_queue.pid && exit;
echo $$ > /var/run/check_mail_queue.pid
while( nm )
do
    /etc/init.d/postfix status || /etc/init.d/postfix start
    sleep 10
    /usr/sbin/postfix flush
done
/etc/init.d/postfix status && /etc/init.d/postfix stop
rm /var/run/check_mail_queue.pid