hi,

> > cText := SUBSTR(cBuffer,nStart,nStop)
>
> This one is an implemantation error in this sample code.
> The third parameter is is not the "last position" it is
> the number of characters to copy to the new string.

Ok, my Mistake ... must be :

cText := SUBSTR(cBuffer,nStart, nStop-nStart)

now i recognize why RAM Curve is not linear growing

cText := SUBSTR(cBuffer,nStart,nStop) // old "wrong" Code
? nStart, nStop , nStop-nStart ,LEN(cText)

291841 291919 78 220080
291921 291999 78 220000
292001 292079 78 219920
292081 292159 78 219840

LEN(cText) will reach "End" of cBuffer String, so it will get "smaller"

511681 511759 78 240
511761 511839 78 160
511841 511919 78 80

Summe 819.196.800 // LEN(cText)
27,19
6399