Re: Varying fields as parameters on procedure calls.

[Scott Klement <rpg400-l@xxxxxxxxxxxxxxxx>]

Alan,

Can you point to this article you're referring to?  I'd like to 
understand what you're referring to.

There's nothing magic about VARYING data types -- they work the same as 
any other data type.  When you pass by VALUE the variable is copied -- 
the whole thing is copied, so if you had 1000A VARYING, it'd copy 1002 
bytes from the caller to the procedure.   When passed by reference (i.e. 
no VALUE keyword) than a pointer (16 bytes) is passed instead, and it 
shares the same memory as the caller.

Personally, because I often interface with other languages like C, C++, 
SQL, etc I would never pass a character string by value.  Many languages 
don't allow it (or allow it, but make it difficult, for instance in C 
you have to use a data structure to pass a a character string by value.) 
 So I would avoid passing a string by value...  (I only use value for 
numerics)

The article you're referring to may be referring to something like 
return values, maybe?   I would like to see it to understand it...

-SK


On 4/10/2015 6:13 PM, Alan Campin wrote:
> Just a quick question. I was reading on article on the web and it stated
> that if I had a varying fields that what would get passed by VALUE would be
> just the first two digits for the length and the actual length of the data.
>
> It has always been my understanding if I had field that was 64K varying and
> I passed it as a parameter that the 64K plus two (or four) bytes for the
> length is what would be passed even I only had say 10 bytes of data.
>
> Since a statement like InParm = *ALL'*'; is valid even though it would
> never be seen by the caller, I don't see any other way it could work except
> to the pass the entire length.
>
> I can pass as *VARSIZE but only if a CONST or by reference or I can pass as
> *STRING with an optional *TRIM which is what I have been doing lately.