Seeking adivce

I am looking for adivce on a better way to do a program. What I have
is a vendor application that prints a PO. We didn't like that PO and
because of how complicated it was, I just wrote a new program to print
the PO how we wanted it. This vendor program had a work file that put
the PO number and some information like that into it. I made a copy of
that file and renamed it and put the exact same information into my
file (the vendor code puts the information into a new member in the
file then deletes the memeber when it is done processing) so it
doesn't get deleted. I did some fancy footwork to put my file in QTEMP
so that more than one person can use this program at once. However,
once in a blue moon, somehow a person gets other people's POs that
they are printing. We have never been able to duplicate that.

My question is this, is this the best way? Is there a better way? All
I truely care about getting is the PO number(s) that they are printing
so I can pass this information to my program (there could be 1 or
there could be 1000 or more, in theory). I am basically looking for
some ideas on how to make this better so we don't have this problem I
described above.

-- 
Mike Wills
iSeries Programmer/Lawson Administrator
koldark@xxxxxxxxx
http://www.koldark.net
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