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From: jik@athena.mit.edu (Jonathan I. Kamens)
Newsgroups: comp.unix.questions
Subject: Re: Does a zombie have a "valid pid"
Message-ID: <1990May25.181610.2342@athena.mit.edu>
Date: 25 May 90 18:16:10 GMT
References: <639@mecky.UUCP> <1990May25.001614.23294@athena.mit.edu> <14276:May2508:53:0790@stealth.acf.nyu.edu>
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Reply-To: jik@athena.mit.edu (Jonathan I. Kamens)
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In article <14276:May2508:53:0790@stealth.acf.nyu.edu>,
brnstnd@stealth.acf.nyu.edu writes:
|> In article <1990May25.001614.23294@athena.mit.edu> jik@athena.mit.edu 
|> (Jonathan I. Kamens) writes:
|> >   Yes.  A zombie process is still a process, even if it's in a weird
|> > state.  As long as that's true, it's still going to have a PID
|> > associated with it, and therefore signals sent to it are going to work.
|> 
|> You're correct up to the last phrase. Signals sent to it aren't going to
|> ``work,'' in the sense that they won't invoke the usual signal handler;
|> QUIT won't dump a zombie. They'll be delivered, but they won't work.

  It's a matter of semantics; I stand by what I said, because I meant
the same thing you did.

  The original poster said that he thought a kill(2) sent to a zombie
process should return -1 (meaning that it "shouldn't work").  I replied
that that's incorrect -- signals sent to a zombie process will "work",
at least from the sender's point of view.

  Perhaps I should have said, "... and therefore sending signals to it
is still going to work."

Jonathan Kamens			              USnail:
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