Re: Re: Basing a field on an unreferenced field(s) doesn't work

[bmorris@xxxxxxxxxx]

>From: rob@dekko.com
>Date: Fri, 11 Jan 2002 13:40:38 -0500
>
>I can understand fields in separate data structures not being contiguous.
>I wouldn't expect them to be.  But, are you saying, that the compiler
>doesn't treat all fields in a file as contiguous?

Yep, that's what I'm saying.  The compiler knows the I/O buffer itself
is contiguous, but it doesn't require the program fields to be contiguous
in storage, nor attempt to make them contiguous.

>What is the best way to move every field of a file into a data structure?
>Obviously you would want to create the data structure as an external data
>structure with the format of the file.  But then how do you get the fields
>moved?  Surely not one at a time?  Can you move a record format into the
>data structure?  Or do you pitch your RPG I/O out and use SQL's select
>into?

Coding the externally-described data structure won't impact your program
in any way performance-wise (for better or worse).  The fields are still
moved one by one.  There may be better support in the future for doing
I/O to externally-described files directly to/from data structures (like
you already can for program-described files).

Barbara Morris