From mboxrd@z Thu Jan  1 00:00:00 1970
From: Kevin Wolf <kwolf@suse.de>
Subject: Re: [RFC][PATCH] Use ioemu block drivers through blktap
Date: Mon, 31 Mar 2008 11:10:06 +0200
Message-ID: <47F0AA6E.2050909@suse.de>
References: <47D569F6.1010209@suse.de>	<47D91D3D.1000005@suse.de>
	<18413.3411.635161.295233@mariner.uk.xensource.com>
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To: Ian Jackson <Ian.Jackson@eu.citrix.com>
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Ian Jackson schrieb:
> Sorry for picking this up now, but I'm trying to reconcile ioemu with
> qemu and I wondered what the purpose of these changes was:
> 
>> +static void qemu_sighup_handler(int signal)
>> +{
>> +    fprintf(stderr, "Received SIGHUP, terminating.\n");
>> +    exit(0);
>> +}
>> +
> 
>> -    signal(SIGHUP, SIG_DFL);
>> +    signal(SIGHUP, qemu_sighup_handler);

I needed a shutdown handler to properly close the blktap connection and
delete the named pipes associated with the qemu-dm instance. When a
domain is destroyed, qemu-dm receives a SIGHUP. However, with the
default SIGHUP handler no atexit functions are called, so I had to add
this handler which performs a clean exit.

Kevin