I have (on Windows) a process started with system(1,...), I have its PID, and I would like to check later whether the process is still running. I can not use waitpid, because this would suspend my program until the process is finished. From the description of the kill function, I thought that sending signal 0 to the process would tell me, whether it is still running: 

sub not_running {
  my $pid=shift;
  0 == kill(0,$pid)
}

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But this always returns true, even though I can see that the process has already finished long time ago. What am I doing wrong?

-- 
Ronald Fischer <ynnor@mm.st>

In reply to Testing whether a process has finished by rovf

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