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/ohp:[-]size            Overlay stash in EMS 4.0, expanded memory.  
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 Syntax:

 Use - to leave memory free.  Size is the size of the overlay stash in
 kilobytes.  It can range from 0 to 16383.

 Description:

 This option stashes the overlay file to EMS memory at runtime. 

 The overlays are stashed as they are  loaded for the first time in the
 overlay pool, as memory allows.  Thereafter, if the  overlay  must be
 reloaded, it will be brought in from EMS memory rather than from disk.
 Stashing can increase speed in the executing program substantially.
 Partial stashing of some overlays in the overlay file may occur if 
 there is not enough memory to stash all of them.  Overlays are placed
 in EMS on a first loaded, first stashed-as-fits, basis.  All EMS memory 
 allocated for use by /ohp is automatically freed at program termination.

 /ohp overlay file stashing will not occur if the overlay manager detects
 less than 80K free EMS or an EMS driver is not present.

 You should use a multiple of 16K to specify size because EMS pages are
 allocated in 16K pages. Odd amounts are rounded up. For example, /ohp:120 
 is the same as /ohp:128.  A minus sign means leave the amount free.  For 
 example, /ohp:-1024 means leave 1024K free (1M) for the executing program
 and use the rest for stashing overlays, (up to the space required).  The
 overlay manager will not take more EMS memory than it needs even if you
 specify more with the /ohp option. For example, if you specify /ohp:4096
 and the overlay manager only needs 640K to stash the entire overlay file, 
 the overlay manager will allocate only 640K of EMS.

 /ohp detects EMS 4.0 automatically and uses an enhanced stashing algorithm
 if EMS 4 (supporting direct lower memory mapping) is available. The direct
 memory mapping algorithm is more speed efficient than the EMS 3.0 algorithm
 of copy-to-page map-out-page and map-in-page copy-from-page.

 /ohp is more useful than /orp in a generic sense, but both can be used
 simultaneously.  /orp will stash an exact image of a swapped-out, active
 overlay for return swap-in, thus eliminating the need for the overlay
 manager to process and fix up overlay offsets when the active overlay is
 brought back in. Typically, you will find a much greater speed increase
 with /ohp stashing, but /orp can also speed up a program if there are
 many active overlay swap-outs.  /ohp allocates EMS after /orp does its
 128K fixed allocation.  If you have a small amount of EMS, it is
 recommended that you use /ohp rather than /orp.

 Use of the EMS page frame for the overlay pool (/ox) prevents EMS 3.0
 overlay file stashing via the /ohp option.  The /ox option automatically
 shuts off such stashing because EMS 3.0 routines must map into the
 EMS page frame that /ox uses to hold the overlay pool that the stashed
 overlay is being copied to. If you use /ohp and /ox, and the /ohp
 routines detect EMS 3.0 usage, then stashing an overlay file to EMS will
 be automatically shut off at runtime.  Note that it is always safe to
 specify both the /ox and /ohp options.  If the WarpLink overlay manager
 detects EMS 4.0 support, then simultaneous use of the EMS page frame
 for the overlay pool and stashing of the overlays to EMS occurs.  If it
 does not detect EMS 4.0 support, then only the EMS page frame for the
 overlay pool will be used.

 The /ohp option has lower priority than the /oht option if both are used. 
 If you specify both the /oht and /ohp options, XMS overlay stashing will
 be used unless at least 80K of free XMS is not available, at which time
 the WarpLink overlay manager will attempt to use EMS for overlay
 stashing.  You may wish to specify both options if your program will be
 operating on a mix of machines that may have either EMS or XMS
 memory.

 Clipper User Notes:

 An initial setting of /ohp:-512  for Clipper programs is recommended.
 This guarantees 512K of EMS remains for your program, plus whatever
 may be left over from stashing the overlay file.  In particular, it is not
 recommended that a Clipper 5 program have no EMS available to it
 during execution. If your program has no need for EMS, then use a
 large /ohp setting to stash the entire overlay file. For example, use a
 setting of /ohp:9000.

 If you use the /ohp option, the Clipper 5 debugger CLD.EXE will not
 function with your program.  Use WarpMod to turn this option off and
 on quickly, if necessary.