PRODUCT  :  Borland C++                            NUMBER  :  660
  VERSION  :  All
       OS  :  PC DOS
     DATE  :  October 19, 1993                         PAGE  :  1/1

    TITLE  :  Dynamically Allocating >64K in Windows 3.0





  In Windows the pointer returned by malloc() is really a selector.
  When you malloc()  more than 64k, Windows will  set  up  multiple
  selectors.  To use  the  pointer you need to increment the offset
  until it reaches 0x0000 again (it always starts at 0x0000).   You
  then need to add a constant value to the segment (Petzold  says 8
  for  protected  mode, 0x1000 for real mode.    See  page  295  of
  Windows  3.0  Power  Programming.),  which  will  give  the  next
  selector!  For example:

  /* Must be far... huge pointers do not work */
  char far *pfoo;

  /* 'pfoo' points to first 64k */
  pfoo = (char far *) farmalloc (1000000ul);

  /* Advance to next segment */
  while (FP_OFF (pfoo) != 0x0000) pfoo++;

  /* Now points to second 64K */
  pfoo = MK_FP (FP_SEG (pfoo) + 8, 0x0000);

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