[zeromq-dev] REQ / REP and inproc sockets

gonzalo diethelm gdiethelm at dcv.cl
Wed Aug 25 23:34:55 CEST 2010

> And yes, I am an ass.

On this high note, allow me two more questions.

1. I use a PUB socket (connects) in my server to publish every five
seconds a heartbeat. From a monitor process I use a SUB socket (binds)
to receive these heartbeats and show them on the console. The weird
thing is this: if I start the server and leave it running for one
minute, it shows it has sent 12 messages over the PUB socket. After that
minute, when I bring up the console, it prints right away the 12
heartbeat messages, and then it goes onto printing the heartbeat
received every five seconds. But I understood the PUB socket operated as
a radio, without saving for later any messages already sent over them.
How is the monitor getting those 12 messages, sent before it was
running? Am I going nuts?

2. What does everyone think about the possibility of compiling 0MQ with
a flag, or maybe passing the socket a setsockopt flag at runtime, so
that it will check that the socket is being used from the same thread as
where it was created from? This could help debugging weird looking
problems, like the one I had been experiencing today.

Gonzalo Diethelm

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