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Date: Thu, 27 Nov 2008 12:16:15 +0000
From: Jamie Lokier <jamie@shareable.org>
Subject: Re: [Qemu-devel] [PATCH] linux-user: Proper exit code for uncaught
	signals
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To: qemu-devel@nongnu.org
Cc: Riku Voipio <riku.voipio@iki.fi>

> > The proper exit code for dieing from an uncaught signal is -<signal>.
> > The kernel doesn't allow exit() or _exit() to pass a negative value.
> > To get the proper exit code we need to actually die from an uncaught
> > signal.

It's nothing like -<signal>, so the comment should be changed.

The general principle of sending yourself a signal to get the right
exit status is good.

> > +    sigfillset(&act.sa_mask);
> > +    act.sa_handler = SIG_DFL;
> > +    sigaction(host_sig, &act, NULL);

What if the SIG_DFL _host_ behaviour is not to terminate the host
process, but it has terminated the guest process?  Awkward one.



> > +    /* For some reason raise(host_sig) doesn't send the signal when
> > +     * statically linked on x86-64. */
> > +    kill(getpid(), host_sig);

Is getpid() always right here, and should tgkill() or tkill() be used when
clone is supported?

-- Jamie