hi Mike,

I recommend using record batches along with io::MemoryMappedFile. You
can write the table with ipc::FileWriter:

https://github.com/apache/arrow/blob/master/cpp/src/arrow/ipc/writer.h#L111

and then read it with ipc::FileReader. If you use MemoryMappedFile,
then the read will be zero-copy (no memory allocated), so ideal for a
multiple-process shared memory setting. You can use one large record
batch or multiple smaller record batches. Let us know if you run into
issues.

Thanks
Wes

On Wed, May 10, 2017 at 7:06 PM, Katelman, Michael
<michael.katel...@cubistsystematic.com> wrote:
> Great!
>
> What I'd like to do is create a table that can be shared among multiple 
> processes. I see, e.g., this in the comments where RecordBatch is defined:
>
>  // A record batch is a simpler and more rigid table data structure intended 
> for
> // use primarily in shared memory IPC. It contains a schema (metadata) and a
> // corresponding sequence of equal-length Arrow arrays
> class ARROW_EXPORT RecordBatch {
>
> But I wasn't entirely sure what the author had in mind.
>
> -Mike
>
> -----Original Message-----
> From: Jason Altekruse [mailto:altekruseja...@gmail.com]
> Sent: Wednesday, May 10, 2017 17:59
> To: dev@arrow.apache.org
> Subject: Re: list scope question
>
> I think we opted to not create a user list yet, as using arrow is likely 
> going to require some willingness to poke around in the library until we can 
> fill out the docs and some more complete example usages. So as far as I know 
> this is the place to ask, what were you looking to do?
>
> On Wed, May 10, 2017 at 2:28 PM, Katelman, Michael < 
> michael.katel...@cubistsystematic.com> wrote:
>
>> Is there a good place for user-oriented arrow questions and discussions?
>> (my apologies in advance if this isn't the appropriate venue)
>>
>> -Mike
>>
>>
>>
>>
>>
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