[futurebasic] Handles & Pointers

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From: Stewart <stharris@...>
Date: Fri, 25 Jun 1999 15:28:23 -0400
I hae always been a bit uncertain about handles and how they are
dereferenced,
so I made up the following chart.
I would appreciate any comments changed, added or deleted.Thanks in
advance.

Stewart

   Data% =   "12,300"

     Relocatable
  Non Relocatable   of Data
  Handle Pointer  Address

Location  "1,234,567" "3,126,594"  "7,183,546"

Contents  "3,126,594" "7,183,546"  "12,300"


  Handle & Pointer locations never move

  & Data locations are moved by the system when more space is needed.
  The handle content is automatically updated


PEEK LONG  4-Bytes "[1,234,567]"  "=3,126,594"  The Handle contents
(Pointer Address)

PEEK LONG  4-Bytes "[3,126,594]"  "=7,183,546"  The Pointer contents
(Data address)

PEEK LONG  4-Bytes "[7,183,546]"  "=12,300"  What you want

PEEK LONG  4-Bytes "[[1,234,567]]"  "=7,183,546"

PEEK WORD  2-Bytes "{[[1,234,567]]}"  "=12,300"  "The contents of
7,183,546"

 "If Data$ = 98,765"
  4-Bytes "[[[1,234,567]]]"  "= 98,765"

 "If Data$ = ""Hello Joe, whadaya know?""!""  "
  X Bytes "{7,183,546}    ="  H
   "{7,183,546}+1 ="  e  etc.

   @Data% =   "7,183,546"  Address of Data