in reply to No child processes - system limit?

Normally, you'd get this error (ECHILD) if you wait for a child, but there is no child, e.g. 

$ perl -e 'die $! if wait == -1'
No child processes at -e line 1.

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In other words, I'm not sure if this is (directly) related to some resource limit at all... (though, of course, it might be a follow-up error of some code doing a wait for a child that never had been created, due to a resource limit like memory, or max children per user).

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Re^2: No child processes - system limit?
by clinton (Priest) on Apr 01, 2010 at 14:15 UTC
    Well, the reason I'm thinking resource limit is that this only occurs when busy, and then a couple of seconds later it works fine again.

    The docs for select indicate that this is the select(2) system call, but the docs for that say the following:

    ...On error, -1 is returned, and errno is set appropriately;...

    and lists the following errors:
    • EBADF
      An invalid file descriptor was given in one of the sets. (Perhaps a file descriptor that was already closed, or one on which an error has occurred.)
    • EINTR
      A signal was caught; see signal(7).
    • EINVAL
      nfds is negative or the value contained within timeout is invalid.
    • ENOMEM
      unable to allocate memory for internal tables.
    ... none of which correspond to the no child processes, and leaving me at a bit of a loss
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[d/l]
[select]

      What do you get for 

      $ getconf CHILD_MAX

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      (or getconf -a, just in case...)

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[d/l]
[select]
        for getconf CHILD_MAX i get: 27968

        for getconf -a

        Read more... (13 kB)

        any of these mean anything to you?

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[d/l]
[select]

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