INT 21 P - Phar Lap 386/DOS-Extender VMM - NEW LOAD PROGRAM FOR DEBUG
        AX = 252Ah
        DS:EDX -> ASCIZ program name
        ES:EBX -> parameter block (see AX=2512h)
        ECX = size of LDT buffer in bytes
        ESI = bit flags
            bit 0: allow demand paging rather than loading entire program
            bit 1: demand page from swap file rather than from .EXP
Return: CF clear if successful
            EAX = VMM handle or FFFFFFFFh if none
            ECX = number of descriptors in LDT buffer
        CF set on error
            EAX = error code
                02h file error
                    EBX = file error code (see below)
                    ECX = DOS error code if EBX=1,2,3, or 8
                08h insufficient memory
                    EBX = memory error code (see below)
                80h LDT buffer too small
                87h called twice without intervening call to AX=2531h
SeeAlso: AX=2512h,AX=2517h,AX=2529h,AX=2531h

Values for file error code:
 01h    DOS open error
 02h    DOS seek error
 03h    DOS read error
 04h    not an .EXP or .REX file
 05h    invalid file format
 06h    -OFFSET is not a multiple of 64K
 07h    -NOPAGE incompatible with -REALBREAK/-OFFSET
 08h    DOS error loading .EXE file

Values for memory error code:
 01h    out of physical memory
 02h    out of swap space
 04h    unable to change extended memory allocation
 05h    -MAXPGMMEM exceeded
 06h    insufficient low memory to REALBREAK value
 07h    insufficient low memory for PSP and environment

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