A simple batch OS may be described as a set of three processes interacting as follows: You must use P() and V() function. Process BATCH OS semaphore in=out=1, card=line=0, fcard=fline=1; process reader; begin while(1) read record from input device; deposit record in input buffer end; process main; begin while(1) fetch record from input buffer; process record and generate output line; deposit line in output buffer end; process printer; begin while (1) fetch line from output buffer; print line on output device end; end Fill in the blanks if you need using semaphore operations to properly buer the input data flows from the reader to the main function, the output data that flows from main to the printer.