2   How much memory do 5.0 applications require?
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     The size of the executable (.EXE) file is only indirectly related
     to the amount of free memory required to successfully run the
     application.

     The amount of memory needed to successfully run a particular
     application depends primarily on its load size and fixed-memory
     requirements.  A general rule of thumb is that an application will
     require from 100K to 200K in addition to the load size reported by
     .RTLink.  For large applications that use most of the features of
     Clipper, the 100K figure is usually a bare minimum; execution may be
     slow due to heavy swapping activity by the VMM unless Expanded Memory
     is available.

     The memory requirements of a Clipper 5.0 application can be roughly
     divided into three categories:

     .  Load Size

        This is the memory needed to initially read the application's
        executable image into memory.  The load size is determined at link
        time; it is always the same for a given .EXE.  .RTLink displays the
        load size in parentheses at the end of every link.  Example:
        (203K).  Load size is affected only slightly by the amount of
        compiled Clipper code in the application (this is because, by
        default, all compiled Clipper code is dynamically overlayed, see
        above).

        However, load size is significantly affected by the amount of
        non-Clipper (C and Assembler) code being used.  This includes
        Clipper support code and third party library code.  Linking with a
        pre-linked library (.PLL) can unnecessarily increase load size if
        your application is not actually using all of the code in the .PLL.

        For information on statically overlaying C and assembler code and
        building various configurations of pre-linked libraries refer to
        Chapter 4 of your Programming and Utilities Guide.

     .  Fixed-Memory Allocations

        Fixed-memory is the memory allocated for system tables and other
        non-virtualized data.  Memory allocated by C or Assembler functions
        (for example, Summer '87 versions of third party libraries or
        overlay managers) is usually fixed memory.  The fixed-memory
        requirement depends on which features of the system are being used.
        For most Clipper applications it ranges from 16K to 64K.  Third
        party libraries or overlay managers which allocate fixed memory may
        increase this requirement, as may certain Clipper programming
        practices.

     .  Swap Space

        Swap space is the memory used by the Virtual Memory Manager (VMM) to
        swap virtualized data in and out of main memory.  By default,
        the VMM uses all available memory as swap space; fixed allocations
        decrease the amount of swap space available.