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Date: Wed, 30 Mar 2011 19:39:31 +0100
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Subject: Re: [Qemu-devel] [PATCHv3] report that QEMU process was killed by a
	signal
From: Peter Maydell <peter.maydell@linaro.org>
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To: Gleb Natapov <gleb@redhat.com>
Cc: qemu-devel@nongnu.org

On 15 March 2011 11:56, Gleb Natapov <gleb@redhat.com> wrote:
> Currently when rogue script kills QEMU process (using TERM/INT/HUP
> signal) it looks indistinguishable from system shutdown. Lets report
> that QEMU was killed and leave some clues about the killer identity.

Unfortunately this patch causes qemu to segfault when killed
via ^C (at least on my Ubuntu maverick system). This is because
it registers a signal handler with sigaction, but then later
the SDL library is initialised and it reinstalls our handler
with plain old signal:

        ohandler = signal(SIGINT, SDL_HandleSIG);
        if ( ohandler != SIG_DFL )
                signal(SIGINT, ohandler);

This is clearly buggy but on the other hand SDL is pretty widely
deployed and it's the default QEMU video output method, so I think
we need to work around it :-(

The most straightforward fix is to get the signal number from
argument one and not to bother printing the PID that killed us.

-- PMM