Red ZeroMQ from Red(not Red/System)

test-server.red

Red [
  Title: "Red Jupyter kernel implementation"
  Author: "Intey"
  File: "%kernel.red"
  Tabs: 4
  License: "MIT"
  ; Needs: ['json 'zeromq] ;; waiting for 0.8.0
]

#system [
  #define ZMQ_ASSERT(r) [
    if r < 0 [print-line ["ZMQ [" zmq/errno "]: " zmq/strerror zmq/errno ]]
  ]
  #include %ZeroMQ/ZeroMQ.reds
]

start-server: routine [
  /local
    ctx
    responder
    r 
    buffer
    bytes
][
  ctx: zmq/ctx_new
  responder: zmq/socket ctx ZMQ_REP
  print-line ["ZMQ Context:   " ctx]
  print-line ["ZMQ Responder: " responder]
  r: zmq/bind responder "tcp://*:5556"
  ZMQ_ASSERT(r)
  if r <> 0 [
    print-line  "ZMQ bind failed!"
    quit -1
  ]
  r: zmq/setsockopt responder ZMQ_SUB as byte-ptr! "" 0
  ZMQ_ASSERT(r)

  buffer: allocate 256
  bytes: 0
  forever [
    print-line "Waiting for request..."
    bytes: zmq/recv responder buffer 255 0
    ZMQ_ASSERT(bytes)
    if bytes >= 0 [
      if bytes > 255 [bytes: 255]
      bytes: bytes + 1
      buffer/bytes: #"^@" ;to create valid c-string ending just in case
    ]
    print-line ["Received request: " as c-string! buffer]
    r: zmq/send responder as byte-ptr! "World" 5 0
    ZMQ_ASSERT(r)
  ]
]

start-server