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Date: Fri, 28 Aug 2015 14:35:50 +0100
From: "Daniel P. Berrange" <berrange@redhat.com>
Message-ID: <20150828133550.GQ28526@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH] hw/usb/bus.c: print device ID when 'info
 usb' used
Reply-To: "Daniel P. Berrange" <berrange@redhat.com>
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To: Programmingkid <programmingkidx@gmail.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>, qemu-devel qemu-devel <qemu-devel@nongnu.org>

On Fri, Aug 28, 2015 at 09:08:12AM -0400, Programmingkid wrote:
> 
> On Aug 28, 2015, at 7:50 AM, Gerd Hoffmann wrote:
> 
> > On Mo, 2015-08-24 at 15:13 -0400, Programmingkid wrote:
> >> +            monitor_printf(mon, "  Device %d.%d, Port %s, Speed %s
> >> Mb/s,"
> >> +                                "Product %s, ID %s\n",
> >> +                           bus->busnr, dev->addr, port->path,
> >> +                           usb_speed(dev->speed),
> >> +                           dev->product_desc, dev->qdev.id);
> >> 
> > 
> > dev->qdev.id can be NULL.
> > 
> > cheers,
> >  Gerd
> 
> That isn't a problem. It will just say "null" when it is printed.
> No crash or garbage text.

Handling of '%s' with NULL is undefined by the standard. Linux
glibc prints the string "null", but other implementations can
crash.

Regards,
Daniel
-- 
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