Here is how you connect to a server (as a client) if your goal is ONLY to PULL data (read).
<?php
$context = new ZMQContext();
$sock = new ZMQSocket($context, ZMQ::SOCKET_PULL);
$sock->connect("tcp://ADDRESS:3000");
while (true)
{
$request = $sock->recv(); # recv is blocking by default, no need to put timers.
printf ("Received: %s;%s", $request, PHP_EOL);
}
?>
if you want to reply, you'll need to use a pair socket (ZMQ::SOCKET_PAIR), then you can use:
$sock->send("data to send");
Also, if instead of you connecting to clients, clients connects to you, use the bind method instead of connect.
EDIT: use the PUSH socket type on the other side if you use the pull here, else, use the pair socket on both sides.