I've noticed that the unsubscribe callbacks in roscpp, set up with advertise options, don't get called if the publisher doesn't publish any messages before the disconnection.

Specifically:

• Set up publisher with subscribe/unsubscribe callbacks
• Subscribe to topic, subscribe callback gets called
• Don't publish messages
• Unsubscribe to topic, unsubscribe callback doesn't get called

Attached is a modified version of talker.cpp to test this problem. To verify:

• Run modified talker.cpp
  • It won't publish
• Run "rostopic echo chatter", then ctrl-C a few times
• Run "rostopic info chatter" to make sure topic not subscribed to
• Unsubscribe callback never gets hit.

trac data:

• Owner: straszheim
• Reporter: watts
• Reported at: Tue Mar 15 13:41:00 2011
• URL: https://code.ros.org/trac/ros/ticket/3403