RE: Parameter prototype question

[J.Beckeringh@xxxxxxxxxxxxxxxxxxxxxxxxxx]

David,

There is no such thing as an output parameter. There are input-only 
parameters (CONST and VALUE), input/output parameters and one return 
value. The return value is used for the boolean (success / found, I 
presume), so you can only use an input/output parameter for the display 
field. The way you have coded it, you are passing a 7-byte field 
(DisplayField_myDossier) to a procedure that is going to put 9 bytes 
there. Think of it as buying wine:

D GetWine          PR                 LIKE ( Ref_BottleOfWine)   
D   money                             LIKE ( Ref_Money ) CONST 

In this case you give the money (input parameter) to the merchant and he 
returns a bottle of wine (return value).

D GetWine          PR              N
D   money                             LIKE ( Ref_Money ) CONST 
D   bottle                            LIKE ( Ref_Bottle)

In this case you give the money (input parameter) and an empty bottle 
(input/output parameter) to the merchant and he tells you 'Yes, I have 
wine' or 'No, I am sold out' and if Yes, he fills your bottle with wine. 
If your bottle is to small, it will overflow.

Joep Beckeringh



> David FOXWELL 
>
> One more post before I drop this thread!
>
> Here I want to populate a display field before showing the screen :
>
> IF NOT GetMyDossier ( inputParm : DisplayField_myDossier );
>
> D GetMyDossier     PR              N  
> D inputParm                           LIKE ( Ref_InPutParm ) CONST  
> D myDossier                           LIKE ( Ref_myDossier ) 
>
> DisplayField_myDossier is 7A and Ref_myDossier is 9A so it won't 
> compile like that. Ref_myDossier has been prolonged to 9A in our 
> data dictionary, but the actual length of dossiers is 7A. So, I 
> <want> the parameter that is returned to be truncated. I put VALUE 
> on it so that it will compile. I hope I've done right as I've not 
> used this before.
>
> Still, I find it baffling that the compiler protects me from 
> truncating the output parameter but I not the input parameter that 
> although I have indicated <don't change this parameter> by the use of 
CONST.