ZeroMQ

The Socket API

To be perfectly honest, ØMQ does a kind of switch-and-bait on you, for which we don’t apologize. It’s for your own good, and it hurts us more than it hurts you. It presents a familiar socket-based API, which requires great effort for us to hide a bunch of message-processing engines. However, the result will slowly fix your world view about how to design and write distributed software.

Sockets are the de facto standard API for network programming, as well as being useful for stopping your eyes from falling onto your cheeks. One thing that makes ØMQ especially tasty to developers is that it uses sockets and messages instead of some other arbitrary set of concepts. Kudos to Martin Sustrik for pulling this off. It turns “Message Oriented Middleware,” a phrase guaranteed to send the whole room off to Catatonia, into “Extra Spicy Sockets!,” which leaves us with a strange craving for pizza and a desire to know more.

Like a favorite dish, ØMQ sockets are easy to digest. These sockets have a life in four parts, just like BSD sockets:

• We can create and destroy them, which go together to form a karmic circle of socket life (see zmq_socket(), zmq_close()).

• We can configure them by setting options on them and checking them if necessary (see zmq_setsockopt(), zmq_getsockopt()).

• We can plug them into the network topology by creating ØMQ connections to and from them (see zmq_bind(), zmq_connect()).

• We can use them to carry data by writing and receiving messages on them ...