INT 21 U - DOS 4.0+ - COMMIT FILE                                               
	AH = 6Ah
	BX = file handle
Return: CF clear if successful
	    AH = 68h
	CF set on error
	    AX = error code (06h) (see #01680 at AH=59h/BX=0000h)
Note:	identical to AH=68h in DOS 5.0-6.0; not known whether this is the case
	  in DOS 4.x
SeeAlso: AH=68h