Y U NO WORK?!!!!

gistfile1.rb

# here's the dealer socket in one process
require 'ffi-rzmq'

@context = ZMQ::Context.new(1)
@sock = @context.socket(ZMQ::XREQ)
@sock.bind("tcp://*:5550")

count = 0
while true do
  count += 1
  puts count
  @sock.send_string("#{count} messge", 0)
  sleep 1
end

# and here's the REP socket in another process
require 'ffi-rzmq'

@context = ZMQ::Context.new(1)
@socket = @context.socket(ZMQ::REP)
@socket.connect("tcp://localhost:5550")

while true do
  puts "attempting recv_string"
  puts @socket.recv_string
end

# and the output on the Dealer side:
# 1
# 2 
# 3
# ...

# and on the REP side:
# attempting recv_string

# then nothing else. the dealer keeps going, but the REP is just stuck. If I don't start the REP then the 
# dealer just waits after the first message.

Like I said, it's good practice to have the receiver(s) up and running first.

For a setup similar to the one you describe, I always put a QUEUE device in between the producer and consumer. I find it easier to manage having each producer (and each consumer) connect to a single address (the device). The way you describe your setup, each producer would have to know the address of every consumer; I find that to be more fragile in my environment, so I use devices to simplify the topology.

Either way will work. 0mq gives you lots of flexibility.