Hi,
I am using cilk api, one parent process sends one message to 5 child processes. But each child process receives the message many times. Why?
Following is my code:
(load "args.lsp")
(parse-args)
(setq process-number (int (ArgsTree "--process-number")))
(define (child-process)
(setq ppid (sys-info 6)) ; get parent pid
(setq cur-pid (sys-info 7))
(while true
(until (receive ppid msg)
(append-file (string cur-pid ".log") (string msg "n"))
(sleep 1000)
)
)
)
; parent starts child processes
(dotimes (i process-number)
(spawn 'result (child-process) true)
)
;; parent send one msg to each child process
(setf child-process-list (sync))
(println "child-process-list: " child-process-list)
(dolist (cpid child-process-list)
(println "child process: " cpid)
(send cpid "test msg")
)
;; quit in 10 seconds
(sleep 10000)
(abort)
(exit)
to spawn 5 child processes, use this command
./run-task.lsp --process-number=5
Then in five child process log files, I have these
Quote
nil
test msg
test msg
test msg
test msg
test msg
test msg
test msg
test msg
test msg
My questions are:
1. why get nil message
2. why get one message repeatedly
3. why receive function needs parent process id(sender id) instead of child process id(receiver id)
1 and 2: The printout happens in the
3. I suppose it's to identify the sender; the child process could have its own children sending to it.
Thanks, ralph.
After replace until with if, it works.
(define (child-process)
(setq ppid (sys-info 6)) ; get parent pid
(setq cur-pid (sys-info 7))
(while true
(if (receive ppid msg)
(begin
;; get new message from queue
(append-file (string cur-pid ".log") (string msg "n"))
)
(begin
;; get nothing from queue, sleep 1 second
(sleep 1000)
)
)
)
)