BEGINAREA                     Specify start of dynamic overlay area
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 Purpose  : Specify the start of a dynamic overlay area

 Syntax   : BEGINAREA

 The BEGINAREA command is used to specify to the linker the start of an
 overlay area in the output file. Each BEGINAREA should have a corresponding
 ENDAREA to indicate the end of the overlay area.

 With static overlays BEGINAREAs, and therefore overlay areas, may be nested
 within one another so long as there is a corresponding ENDAREA for each
 BEGINAREA. This allows the developer to create a structure of overlays
 within an area to use the minimum amount of memory for the maximum number of
 overlay routines.

 With Blinker dynamic overlays, as opposed to static overlays, the mutual
 dependency of each overlay procedure or file is unimportant. Also, the
 multiple nested overlay areas associated with static overlays are no longer
 necessary, although multiple overlay areas may be helpful in ordering the
 included libraries. The BEGINAREA and ENDAREA commands are simply treated as
 markers to the beginning and end of code which is to be overlaid.

 For most compilers, the .OBJ files listed between a BEGINAREA and ENDAREA
 are managed at runtime on a segment basis, i.e. the whole CODE segment for
 each .OBJ is loaded into memory whenever any function or procedure within
 that .OBJ file is called.

 For more details on how functions and procedures may be kept in separate
 segments to reduce the overlay unit size, please refer to the appropriate
 compiler manual for the language being used.

 Note for CA-Clipper:

 All CA-Clipper Summer '87 .OBJ files listed between a BEGINAREA and ENDAREA
 are managed at runtime on a procedure or function basis, no matter how many
 procedures or functions are present in the .OBJ file. Therefore excessively
 large procedures and functions should be avoided. The CA-Clipper 5.x dynamic
 paging system automatically breaks procedures down into 1kb pages for
 improved execution speed, so this is not a concern.