Example doesn't compile #332
Description
When trying to compile the provided example:
[bart@samadhi zmqtest]$ g++ --std=c++17 main.cc
main.cc: In function ‘int main()’:
main.cc:9:19: error: ‘buffer’ is not a member of ‘zmq’
sock.send(zmq::buffer(m), zmq::send_flags::dontwait);
^~~~~~
main.cc:9:35: error: ‘zmq::send_flags’ has not been declared
sock.send(zmq::buffer(m), zmq::send_flags::dontwait);