CLOSE #1:CLR :DIM Z$(10):Z$="D1:DOS.SYS"›? "}Write DOS.SYS to which drive?":OPEN #1,4,0,"K:":GET #1,Z:CLOSE #1:IF Z<49 OR Z>56 THEN STOP ›? "śPut Disk in Drive ";Z-48;" and Press RETURN.":Z$(2,2)=STR$(Z-48):OPEN #1,4,0,"K:":GET #1,Z:CLOSE #1›? "śWriting DOS.SYS to Drive ";Z$(2,2);".   ":OPEN #1,8,0,Z$:CLOSE #1›