Re: [protobuf] Can I memcpy protobuf C++ objects if they only contain fixed length fields?

[Yan Yan]

ty

On Sunday, May 15, 2016 at 7:25:07 AM UTC+8, Feng Xiao wrote:
>
> On Sat, May 14, 2016 at 8:13 AM, Yan Yan  
> wrote:
>
>> No strings, no int64, no int32, no repeated fields.
>> Only sfixed64, sfixed32, nested messages.
>> Are there any dynamic allocation?
>>
> Yes.
>  
>
>> Are there any pointers?
>>
> Yes.
>  
>
>> Is there a subset of protobuf datatypes that I can use to make fixed size 
>> objects that works on memcpy?
>>
> No. Even a complete empty protobut message cannot be memcpy.
>  
>
>> Will the sizeof() operator work? Ideally they should work like C structs 
>> of fixed size, and they come with a higher level API. The wire format is 
>> good for cross-language compatibility. Thx.
>>
> Protobuf C++ objects are not POD and you can't memcpy it.
>  
>
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>
>

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Re: [protobuf] Can I memcpy protobuf C++ objects if they only contain fixed length fields?

['Feng Xiao' via Protocol Buffers]

On Sat, May 14, 2016 at 8:13 AM, Yan Yan  wrote:

> No strings, no int64, no int32, no repeated fields.
> Only sfixed64, sfixed32, nested messages.
> Are there any dynamic allocation?
>
Yes.


> Are there any pointers?
>
Yes.


> Is there a subset of protobuf datatypes that I can use to make fixed size
> objects that works on memcpy?
>
No. Even a complete empty protobut message cannot be memcpy.


> Will the sizeof() operator work? Ideally they should work like C structs
> of fixed size, and they come with a higher level API. The wire format is
> good for cross-language compatibility. Thx.
>
Protobuf C++ objects are not POD and you can't memcpy it.


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> For more options, visit https://groups.google.com/d/optout.
>

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