How to get return value of every spawn process iteration

[nanxiao]

Hi all,



Greeting from me! I am a newbie of newLISP, and want to implement a simple feature which launches processes according to CPU number:  

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(import "libc.so" "sysconf")

(constant '_SC_NPROCESSORS_ONLN 503)

(define (report pid)
    (println "process: " pid " has returned"))

(define cpu-num (sysconf _SC_NPROCESSORS_ONLN))

(set 'result-array cpu-num)

(dotimes (i cpu-num)
(spawn 'p (println i)))

(until (true? (sync 10 report)))

(exit)


I know following code will let p gets only one result:

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(dotimes (i cpu-num)
(spawn 'p (println i)))


I want to use an array to hold every process's return value, but following code is not invalid:

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(set 'result-array cpu-num)

(dotimes (i cpu-num)
(spawn (result-array i) (println i)))


So how can I get return value of every spawn process iteration in for-loop? Thanks very much in advance!



Best Regards

Nan Xiao

[rrq]

You could do something like this

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(dotimes (i cpu-num)
   (spawn (last (push (sym (string "ret" i)) returns -1)) (println i)))
That'd make returns be a list of the return symbols, letting you do

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(eval (returns k)) to obtain the return value of the k:th sub process.



Or, you may want an association list, as with the following

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(dotimes (i cpu-num)
    (let ((p (sym (string "ret" i))))
        (push (list (spawn p (println i)) p) returns -1)))
Then you'd get the return value via

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(eval (lookup pid returns))

It goes without saying, that the return values won't be set until the sub processes have finished.

[nanxiao]

@ralph.ronnquist:



Thanks very much for your help!