Chicken Scheme bindings for the lightweight ZMQ-alternative, nanomsg. There exists Chicken ZMQ bindings, but this turned out to be a little troublesome with zmq_poll blocking other srfi-18 threads.

Nanomsg is smaller, written in C, has a simplified API (sockets are simple ints), no multipart messages, and has explicit support for poll on a socket's recv file-descriptor.

This egg requires nanomsg-0.4-beta. Not tested on nanomsg-0.5-beta.

These bindings are incomplete. All protocols and transport types should be supported. However, socket options (nn_setsockopt and nn_getsockopt) aren't supported with the exception of nn-subscribe. If you're missing something, please create github issues!

Currently supported:

• nn-socket records types with finalizer
• nn-bind and nn-connect
• nn-send and nn-recv
• non-blocking nn-recv with (thread-wait-for-i/o!)
• nn-subscribe for (nn-socket 'sub) sockets

Favored TODO's:

• support socket options
• bundle nanomsg itself?

All of nanomsg's protocols are supported:

• Request/reply protocol (req rep)
• Publish/subscribe protocol (pub sub)
• Survey protocol (survey respondent)
• Pipeline protocol (push pull)
• One-to-one protocol (pair)
• Message bus protocol (bus)

;; test.scm
(use nanomsg)

(define s (nn-socket 'rep))
(nn-bind s "tcp://127.0.0.1:22022")

(let loop ((n 0))
  (nn-send s (conc (nn-recv s) " " n))
  (loop (add1 n)))

(nn-close s)

then test with the brilliant nanocat util that comes with nanomsg:

$ csi -s test.scm &
$ nanocat --req -l22022 -D"bottles of beer:" -A --interval 1