local variable is changed when changing global variable inside procedure - pl1

"Bjørn Solbrå" <bjs@privat.vps.no> wrote in message
news:dthv0j$hb9$1@bat-news01.banetele.basefarm.net...
>A procedure call
>
> CALL OVERFØR_PKU_PKI(DCLV012223.VNR_ISO,' ',
> DCLV012223.AKS_BEV_AKSJEBEH);
>
> to the following procedure
>
> OVERFØR_PKU_PKI: PROC(VNR,TYPE,SUM);
> DCL VNR CHAR(12);
> PUT SKIP LIST('VNR '!!VNR);
> DCL TYPE CHAR(3);
> DCL SUM FIXED DEC(15);
> TELLER = TELLER + 1;
> DCLV012223 = '';
> .
> PUT SKIP LIST('VNR1 '!!VNR);
>
> gives a result that indicates that the
>
> DCLV012223 = '';
>
> statement has also blanked the VNR variable

Of course. PL/I uses 'call by reference'.

> How can this be possible? I would have expected that a change of a
> global variable inside i procedure should not influate on the local
> variable

If you want to do a 'call by value', enclose it in parentheses on the
call, ie

CALL OVERFØR_PKU_PKI((DCLV012223.VNR_ISO),' ',
DCLV012223.AKS_BEV_AKSJEBEH);

Robert
--
Robert AH Prins
prino at prino dot plus dot com