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Date: Fri, 16 Dec 2011 09:54:38 -0600
From: Anthony Liguori <anthony@codemonkey.ws>
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Subject: Re: [Qemu-devel] [PATCH 1/8] qapi: fix NULL pointer dereference
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: kwolf@redhat.com, qemu-devel@nongnu.org

On 12/16/2011 09:42 AM, Paolo Bonzini wrote:
> On 12/16/2011 04:23 PM, Anthony Liguori wrote:
>> Ok. I think nullable strings are not a good idea simply because it
>> means that a property can have a state that cannot be set.
>
> How is this different from NULL links? (Honest, not trick question :)).

An empty string == NULL for links.

If a pointer is NULL, an empty string is returned.  So get/set is full symmetric.

>> Long term, I want to be able to do something like dump the current
>> device graph to a config file, and then use that config file to recreate
>> the same machine again. A nullable property without a null
>> representation would not allow this.
>
> JSON null is such a representation.

For JSON, but it doesn't map to a config file easily nor does it map to command 
line syntax well.

Regards,

Anthony Liguori

>
> Paolo
>