Errata for Page 180

[chihyang]

The third line from the end of page 180 says:

So the first two items, 300 and 205, are printed by the main thread.

But according to the program on page 181:

let buffer = 0
       in let producer = proc (n)
              letrec
                wait4(k) = if zero?(k)
                           then set buffer = n
                           else begin
                                  print(-(k,-200));
                                  (wait4 -(k,1))
                                end
                in (wait4 5)
          in let consumer = proc (d)
                  letrec busywait(k) = if zero?(buffer)
                                       then begin
                                             print(-(k,-100));
                                             (busywait -(k,-1))
                                            end
                                       else buffer
                  in (busywait 0)
              in begin
                  spawn(proc (d) (producer 44));
                  print(300);
                  (consumer 86)
                 end

205 is printed by subthread. So the text on page 180 might be:

So the first two items, 300 and 205, are printed by the main thread and the subthread respectively.

[mwand]

You are right, of course. I will make an entry in the errata. If you send me your name or email, I will credit you.