www.delorie.com/djgpp/doc/rbinter/27.html   search  
Table 2766

Call the XMS driver "Request upper memory block" function with:
	AH = 10h
	DX = size of block in paragraphs
Return: AX = status
	    0001h success
		BX = segment address of UMB
		DX = actual size of block
	    0000h failure
		BL = error code (80h,B0h,B1h) (see #02775)
		DX = largest available block
Notes:	Upper Memory consists of non-EMS memory between 640K and 1024K
	the XMS driver need not implement functions 10h through 12h to be
	  considered compliant with the standard
	under DOS 5+, if CONFIG.SYS contains the line DOS=UMB, then no upper
	  memory blocks will be available for allocation because all blocks
	  have been grabbed by MS-DOS while booting
SeeAlso: #02759,#02767,#02785,INT 21/AH=58h"UMB"

  webmaster   donations   bookstore     delorie software   privacy  
  Copyright 2000   by Ralf Brown     Updated Jul 2000