Data Area Issue

[RPower@xxxxxxxxxx]

I've searched the archives, but can't quite find an answer to my question 
that I'm looking for.  I have the following piece of code:
     ?* set receipt number
     c     *lock         in        rec#dta
     c                   eval      rec#dta = rec#dta + 1
     c                   eval      precpt# = rec#dta
     c                   out       rec#dta 
There can be mulitple versions of this program at any given time (cash 
receipts) and it seems that if both programs hit this the exact same time, 
one blows up.  My questions are:
1. On the OUT opcode, does it automatically release the locks?  Or should 
I be using the UNLOCK opcode as well?
2. Can I use lock logic here like record lock logic that RPG has?

Thanks,

Ron Power
Programmer
Information Services
City Of St. John's, NL
P.O. Box 908
St. John's, NL
A1C 5M2
Tel: 709-576-8132
Email: rpower@xxxxxxxxxx
Website: http://www.stjohns.ca/
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