Re: wait4(2) do not fail with WNOHANG if there is no child

[Robert Elz <kre%munnari.OZ.AU@localhost>]

    Date:        Sun, 6 Nov 2016 09:34:17 +0100
    From:        Nicolas Joly <njoly%pasteur.fr@localhost>
    Message-ID:  <20161106083417.GA6284%issan.sis.pasteur.fr@localhost>

  | Just encountered a case where wait(4) + WNOHANG do not fail with
  | expected ECHILD when there is no process to wait.

See man 2 wait ...

     When the WNOHANG option is specified and no processes wish to report
     status, wait4() returns a process id of 0.

If you specified WNOHANG it is not an error that there are no processes
available, there are just no processes...

kre