Note: This API calls are shared between DOS and Win16 personality.
DOSX is a specialized version of DPMI. Windows standard and extended mode kernel is a DPMI client app. Standard and extended mode kernel differs minimally and shares common codebase. Standard mode is just DPMI client, exnhanced mode is DPMI client running under Virtual Machime Manager. Both modes shares DPMI interface for kernel communication. The OS/2 virtual DOS Protected Mode Interface (VDPMI) device driver provides Version 0.9 DPMI support for virtual DOS machines. Win16 provides Version 1.0 DPMI support, but reported as 0.9.
Int 31H, AH=07H, AL=03H
Discard Page Contents
AX = 0703h BX:CX = starting linear address of pages to discard SI:DI = size of region to discard (bytes)
if function successful Carry flag = clear if function unsuccessful Carry flag = set AX = error code 8025H invalid linear address (range unallocated)
Discards the entire contents of a given linear memory range. This function is used when a memory object (such as a data structure) that occupies a given area of memory is no longer needed, so that the area will not be paged to disk unnecessarily. The contents of the discarded region will be undefined.
Partial pages and locked pages will not be discarded.
Text based on http://www.delorie.com/djgpp/doc/dpmi/