Re: LVLCHK(*NO)

[Vernon Hamberg <vhamberg@xxxxxxxxxxxxxxx>]

Hi Dave

I'll jump in where angels fear to tread, perhaps.

Your program knows nothing about the new fields - it uses a buffer that 
contains only the other fields it already knows about.

My understanding is, the data in the new fields is not brought into 
memory in any meaningful way - your program won't change them even by 
accident.

Now does the new program use those fields? Probably not. I think there 
will be no ill effects.

Now although I generally support checking the format level, as we use 
SQL more and more, that becomes less used - SQL functions know nothing 
about format level checks.

Anyhow, I'm happy to be found incorrect. Learning happens every day, I hope.

Cheers
Vern

On 1/29/2021 7:11 AM, Dave wrote:
> Hi,
>
>
>
> I was rather surprised to discover that in my current shop, it is a regular
> practice to use files in this way, thus avoiding (sometimes) the need to
> recompile some of the programs sources where they are declared.
>
> I’ve just modified such a file, placing a couple of new fields at the end
> of the DDS. The program seems to function normally. But what happens
> exactly when the program reads the file ? Surely, the memory pointing to
> the new data somewhere is modified. Where is it and how can one be sure
> there can be no ill effects ?
>
>
>
> Thanks !