[zeromq-dev] [PATCH] zmq::msg_t::const_data for const correctness?
sustrik at 250bpm.com
Fri May 27 10:16:52 CEST 2011
On 05/27/2011 10:05 AM, Ilja Golshtein wrote:
> Yes, it was discussed here
> Attaching the patch (again)
> It suggests two overloaded data() methods. The new one is const and
> returns const void*.
Yes. This is a better approach but still doesn't deliver consistent
Implementing CoW behaviour to get the semantics consistent in
std::string way is probably not that good an idea because of the
performance impact of message copying.
One solution that comes to mind is changing the zmq_msg_copy function in
such a way that it closes the original non-const message and produces
two const messages.
That way the user can't shoot himself in the leg by copying a message
object (which makes the buffer shared) and overwriting the data in one
instance behind other instance's back.
int zmq_msg_copy (const zmq_msg_t *src, const zmq_msg_t **dest1,
const zmq_msg_t **dest2);
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