zmq_cpp.txt

zmq_cpp(7)
==========


NAME
----
zmq_cpp - interface between 0MQ and C++ applications


SYNOPSIS
--------
This manual page explains how C++ API maps to underlying C API. To learn about
individual functions and parameters check appropriate C API manual
pages.

For example, to understand 'zmq::socket_t::setsockopt' function check
linkzmq:zmq_setsockopt[3].

All 0MQ constants defined with C API are available with C++ API.


zmq::context_t
--------------
This class encapsulates the functions dealing with initialisation and
termination of 0MQ context. Constructor of the class invokes
linkzmq:zmq_init[3] while destructor calls linkzmq:zmq_term[3].


zmq::socket_t
-------------
This class encapsulates all the functions to deal with 0MQ sockets. Constructor
calls linkzmq:zmq_socket[3], destructor calls linkzmq:zmq_close[3].  Other
functions of the class are mapped to C functions with corresponding names.
'zmq::socket_t::bind' calls linkzmq:zmq_bind[3] etc.


zmq::message_t
--------------
This class encapsulates 'zmq_msg_t' structure and all the C functions that deal
with 0MQ messages.  Constructors of the class invoke corresponding
initialisation functions linkzmq:zmq_msg_init[3], linkzmq:zmq_msg_init_size[3]
and linkzmq:zmq_msg_init_data[3], while destructor invokes
linkzmq:zmq_msg_close[3] function.

Remaining functions are mapped to C functions with corresponding names.
For instance, 'zmq::message_t::copy' is mapped to linkzmq:zmq_msg_copy[3]
etc.

C++ provides an additional function not available with C API.
'zmq::message_t::rebuild' is equivalent to calling linkzmq:zmq_close[3]
followed by linkzmq:zmq_msg_init[3], linkzmq:zmq_msg_init_size[3] or
linkzmq:zmq_msg_init_data[3].  It provides a way to reuse existing
'zmq::message_t' instances to store different message content.


zmq::error_t
------------
All the errors reported using 'errno' mechanism in C API are automatically
converted to exceptions in C++ API.  'zmq::error_t' is derived from
'std::exception' and uses linkzmq:zmq_strerror[3] function to convert the error
code to human-readable string.


zmq::poll
---------
'zmq::poll' function is a namespaced equivalent of raw C linkzmq:zmq_poll[3]
function.


EXAMPLE
-------
----
zmq::context_t ctx (1, 1);
zmq::socket_t s (ctx, ZMQ_PUB);
s.connect ("tcp://192.168.0.115:5555");
zmq::message_t msg (100);
memset (msg.data (), 0, 100);
s.send (msg);
----


SEE ALSO
--------
linkzmq:zmq[7]


AUTHOR
------
Martin Sustrik <sustrik at 250bpm dot com>