in reply to waitpid returns -1 for still running child (Windows)

I cannot reproduce your results with either 5.8.9 or 5.10.1: 

c:\test>\perl32\bin\perl.exe -wle"print $$, ':',  $p=system 1, 'perl -
+le\"print qq[??$$]; sleep 10; print q[exiting]\"'; print waitpid $p, 
+1 while sleep 1"
13960:14028
??13984
0
0
0
0
0
0
0
0
0
0
exiting
14028
-1
-1
-1
Terminating on signal SIGINT(2)

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Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
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Re^2: waitpid returns -1 for still running child (Windows)
by rovf (Priest) on Jul 06, 2010 at 12:21 UTC
    I cannot reproduce your results ...
    Neither do I. That's the problem. I would be much happier if I could reproduce it, but in general, it runs well. I have found one case so far, where it failed, but this case is documented well. It seems to be a rare case, so I hoped someone with good Windows knowledge would know of some exotic circumstance where this problem might show up on Windows.

    -- 
    Ronald Fischer <ynnor@mm.st>
[reply]
[d/l]
      I hoped someone with good Windows knowledge would know of some exotic circumstance where this problem might show up on Windows.

      How is the logging done? Ie. Are they simple prints to the respective log files directly from the applications, or are you using some centralised logging mechanism via pipes or sockets?

      How & where are the timestamps added?

      As for tracking it down more thoroughly, I'd start off by creating a simple UDP logging deamon and have both (all) apps send their messages to that. I'd time stamp them at both ends.

      Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
      "Science is about questioning the status quo. Questioning authority".
      In the absence of evidence, opinion is indistinguishable from prejudice.
[reply]
        Logging is done just by print statements, and the timestamps are calculated at the time the print statement is executed. On the master process, the log entry is printed after waitpid has been received, and on the child process, the log entry is printed after the control file is written, so even if there would be some delay, it would aggravate the problem instead of explain it :-(

        -- 
        Ronald Fischer <ynnor@mm.st>
[reply]
[d/l]

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