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2158

Category: DOS kernel

INT 21 - DOS 2.11+ - GET OR SET MEMORY ALLOCATION STRATEGY

	AH = 58h
	AL = subfunction
	    00h get allocation strategy
		Return: AX = current strategy (see #01679)
	    01h set allocation strategy
		BL = new allocation strategy (see #01679)
		BH = 00h (DOS 5+)
Return: CF clear if successful
	CF set on error
	    AX = error code (01h) (see #01680)
Notes:	the Set subfunction accepts any value in BL for DOS 3.x and 4.x;
	  2 or greater means last fit
	the Get subfunction returns the last value set
	setting an allocation strategy involving high memory does not
	  automatically link in the UMB memory chain; this must be done
	  explicitly with AX=5803h in order to actually allocate high memory
	a program which changes the allocation strategy should restore it
	  before terminating
	Toshiba MS-DOS v2.11 supports subfunctions 00h and 01h, as does the
	  TI Professional MS-DOS v2.13
	DR DOS 3.41 reportedly reverses subfunctions 00h and 01h
SeeAlso: AH=48h,AH=49h,AH=4Ah,INT 2F/AX=4310h"XMS",INT 67/AH=3Fh


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