)
Call NLCACHE/NWCACHE "sideband function" API entry point with:
	BX = function
	    0000h flush request from server
		Return: CF clear if successful at flushing deferred writes
			    AX = 0000h
			CF set on error
			    AX = error code
	    0001h (NWCACHE only) get cache statistics
		ES:DI -> buffer for statistics (see #04122)
		Return: CF clear if successful
			AX = 0000h
			ES:DI buffer filled
	    other
		Return: CF set
			AX = 0001h (invalid function)