2   Use of LIM 3.2 Expanded Memory (EMM)
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     By default, the Clipper 5.0 VMM uses LIM 3.2 Expanded Memory (EMM) as
     secondary storage.  EMM provides fast access to swapped segments.  Up
     to 8MB of EMM can be used.

     Configuration:  EMM usage can be controlled using the E setting in
     the CLIPPER environment variable.  Valid settings are from 0 to 8192
     (units of 1K).  A setting of 0 disables the use of EMM altogether.

     Caution:  Disabling EMM is highly undesirable under Clipper 5.0.
     Although EMM is not required, it allows increased performance for most
     applications.  In a very few cases, limiting EMM usage may be
     desirable.  See the note below under Disk File Buffering.

     Example:  SET CLIPPER=E:2048

     Configuration:  Some disk caching programs use EMM to cache disk
     sectors.  Certain cache programs may cause conflicts with the Clipper
     5.0 VMM system if they assume that application programs never use EMM.
     The BADCACHE setting in the CLIPPER environment variable causes the VMM
     to preserve and restore the state of the EMM page frame before and
     after every EMM access (the EMM page frame is an area in real address
     space through which EMM data is accessed).  This should make Clipper's
     use of EMM undetectable to any other process using EMM.  (Note: on some
     EMM systems the BADCACHE setting may adversely affect VMM performance.
     It should only be used if you experience disk or file corruption
     because of a conflict with a disk cache or other resident software.)

     Example:  SET CLIPPER=BADCACHE