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From: Sean McNeil <sean@mcneil.com>
To: Koryn Grant <koryn@endace.com>
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Subject: Re: kill(pid,0) sends a signal or not?
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On Sun, 2004-06-20 at 22:26, Koryn Grant wrote:
> On Sun, 20 Jun 2004, Sean McNeil wrote:
> 
> > Any info on how threads are suppose to behave when a process does a
> > kill(pid,0) would be greatly appreciated.
> 
> The Single Unix Specification speaks thusly about kill():
> 
> "If sig is 0 (the null signal), error checking is performed but no signal is
> actually sent. The null signal can be used to check the validity of pid."

Thanks, Koryn.  It looks like what I'm seeing with the 0 value is how
kse/pthread is waking up another thread through signalcontext.  All
looks legit.  I thought that it was getting there from a kill().

Cheers,
Sean