[quote="arunava_nag, post:5, topic:1391"] So how do we have call backs from our publisher or subscriber? [/quote] You can have one callback per subscription, I don't know why you'd have a callback for a publisher. We might have callbacks for events like when a subscription is matched on a publisher or something like that, but in typical use cases you'd never have a callback on a publisher... [quote="arunava_nag, post:5, topic:1391"] Has multiple call backs been enabled? [/quote] No, but as I said above, you can have your own list of callbacks which you call in your subscriptions single callback. --- [Visit Topic](https://discourse.ros.org/t/maximum-amount-of-publisher-subscriptions-per-node/1391/6) or reply to this email to respond. If you do not want to receive messages from ros-users please use the unsubscribe link below. If you use the one above, you will stop all of ros-users from receiving updates. ______________________________________________________________________________ ros-users mailing list ros-users@lists.ros.org http://lists.ros.org/mailman/listinfo/ros-users Unsubscribe: