RE: Help... %Len initializing field ?

Hi Jon,

The why behind this...

The C-function I'm talking about is recv() and is used to receive bytes from
a sockets connection.  All this is buffered internally in my program by
means of a variable length field.  Now instead of passing another buffer to
the recv() function, and concatenating this afterwards to the varying field,
I wanted to avoid moving buffers around (string manipulation in RPG is way
to costly).

Since I don't know in advance how many bytes I will be receiving (this is
the result of the C-function), and since the destination is not the
beginning of the varying length field, I just calculated a pointer to the
correct offset in the varying field (in the test example I gave I had a
based buffer, but this was only for demonstration).  Once the recv()
function completed, I could then do a %Len(Var) = %Len(Var) + rc ... but
this went wrong.

Anyway, solved it via a based of a 5U 0 field on the varying length field.

Kind regards,
Paul

-----Original Message-----
From: Jon Paris [mailto:Jon.Paris@partner400.com]
Sent: 03 June, 2002 23:42
To: rpg400-l@midrange.com
Subject: Help... %Len initializing field ?

...

Paul - the other answers you received are correct in that you need to set
the length before you start.  My question to you is why one earth do you
want to do this much work?

If you need to pass a string pointer to a C function use the
Options(*String) on the proto and the compiler does the work for you.  If
(as seems to be the case here) you are simply passing a pointer and the
function places a string in that location, then all you need to do is use
%Str to de-reference the pointer and you can load the data into a fixed or
variable length field.

In your case:

 Buffer = %Str(pFixed);

appears to be what you need.  Is there a reason why this won't work for you?



Jon Paris
Partner400


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