[zeromq-dev] [PATCH] add zmq::version to C++ API

[Martin Sustrik]

On 03/15/2011 11:20 AM, Hoelzlwimmer Andreas wrote:
> Passing those parameters by reference gives you additional safety for the call.
> Additionally, in C++ lessons given to me, parameters by reference, especially for basic data types such as integers, were a sign for in/out parameters

The problem is that reference is visible only in the prototype of the 
function, not with actual usage:

int i;
fx (i); // is this a reference or pass-by-value?

Thus, 0MQ C++ API uses pointers instead. See how send and recv work:

void send (message_t &msg);
void recv (message_t *msg);

And in actual usage:

zmq::message_t msg;
s.send (msg);

and:

zmq::message_t msg;
s.recv (&msg);

Martin