INT 21 U - DR DOS 5.0-6.0 - SHARE/HILOAD CONTROL                                
	AX = 4457h
	DH = subfunction
	    00h enable/disable SHARE
		DL = 00h disable
		   = 01h enable
		   else Return: AX = ???
	    01h get HILOAD status
		Return: AX = status
			    0000h off
			    0001h on
	    02h set HILOAD status
		DL = new state (00h off, 01h on)
		Return: AX = ???
	    other
		Return: AX = ???
Note:	This was seen called by COMMAND.COM of DR DOS 6.0; it does not seem
	  to be supported by Novell DOS 7
SeeAlso: AX=4457h/DX=FFFFh