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Internal and External Overlays

   You can create two kinds of overlays, internal and external, with
   PLINK86-Plus.  Both types function identically.  They differ only in
   that external overlays are contained in separate files, identified
   with the .OVL extension.

   Internal overlays are created with the SECTION FILE statement.  They
   are included in the .EXE file.  Usually the main load file and all
   (internal) overlays are written to the same output file.  The
   overlays appear at the end of the file and the operating system is
   unaware of their presence when loading the program.  Thus, with
   internal overlays, a directory search is not required to find the
   overlays files and the program executes faster than the same program
   with external overlays.

   However, external overlays may be useful in several cases, such as
   when your application does not fit on a single floppy disk, or when
   you need to determine the actual size of the overlays.  External
   overlays may be transferred on a disk other than the one on which the
   main program file resides.  Overlay files need only be available to
   the program at execution time.

   Overlays are placed in separate files with the SECTION statement's
   INTO option.  To create external overlays rather than internal,
   modify the example RESPONSE (.LNK) FILE file to reflect the
   following:

   BEGINAREA
        SECTION INTO ADD_EDIT.OVL FILE ADD, EDIT
        SECTION INTO RPT.OVL FILE RPT
        SECTION INTO UTILITY.OVL FILE REINDX, B_C
   ENDAREA