Sync

Task/Synchronous-concurrency/Icon/synchronous-concurrency.icon

@@ -1,28 +1,19 @@
-procedure main()
-   local prod, cons
-   prod := create producer("input.txt")
-   cons := create consumer(prod)
-   @cons
+procedure main(A)
+    fName := A[1]|"index.txt"
+    p := thread produce(fName)
+    c := thread consume(p)
+    every wait(p | c)
 end
 
-procedure producer(fname)
-   local f
-   f := open(fname) | stop("Unable to open ", fname)
-   # send what we read [read(f)] to the consumer (&source)
-   while read(f) @ &source
-   # send it 'null' which we use as a signal to request count
-   write("count = ", &null @ &source)
+procedure produce(fName)
+    every !open(fName)@>>    # drop messages in p's outbox (blocking whenever box is full)
+    @>>                      # Signal consumer that p is done
+    write("count is ",<<@)   # block until message in p's inbox
 end
 
-procedure consumer(p)
-   local value, i
-   i := 1
-   value := @p
-   while \value do {
-      write("=> ",value)
-      value := @ &source
-      i := i + 1
-   }
-   # send producer our count
-   i @ &source
+procedure consume(p)
+    i := 0
+    while write(\<<@p) do (i+:=1)  # loop until empty message in p's outbox
+                                   #    (blocking until each message arrives)
+    i@>>p                          # put row count into p's inbox
 end