V86MMGR_GetPgStatus

include v86mmgr.inc

mov     ebx, VMHandle
mov     ecx, PageNum
VxDcall V86MMGR_GetPgStatus

Gets the status of a page. This service is only available for Windows version 3.1 and later. Uses EAX, Flags.

Returns with one of these values in the EAX register:

V86PS_EMM	Page belongs to EMM driver.
V86PS_MAP	Page belongs to mapper.
V86PS_UMB	Page is part of a UMB.
V86PS_XMS	Page belongs to XMS driver.

The V86PS_XMS value is not necessarily set.

VMHandle: Handle of the virtual machine to get information for. If this parameter is zero, the service retrieves global information.
PageNum: Page number in the virtual 8086-mode address space. Must be in the rage 0 through 110h.

You can use this service to determine various aspects of what a specific page is being used for. This service can be called with any page number in the 0 through 110h range, but it is intended to return useful information only for pages above the last V86 page. One particular use of this service is to determine if a page is part of an imported high-memory UMB.

This service will not work if called during the Sys_Critical_Init message. The service is not valid until the Device_Init message. Calls during Device_Init only return useful information if paging import from a LIMulator/UMBulator is performed. In cases where no paging import exists, the information will not be correct until after the Init_Complete message.