Hi folks, I'd like my applications to be able to read bagfiles in an offline manner and process them as fast as possible. But they should also be able to run online and receive messages. Currently I'm using nodehandles and subscribers for the online mode. In this case, the messages are instantiated for me, and I just have to implement the appropriate callback functions. For the offline mode, however, I use the bagreader, with a View and an iterator. Then I check the topic of the messages, instantiate them, and do stuff with them. This is very inconvenient, it would be much nicer and less code if I could use the callbacks for the offline mode as well: the bagreader should read the log file, instantiate the messages, and call the callbacks, all in a single thread, so that its executed as fast as possible, and as slow as necessary. Is there a way to do this in ROS? And why wasn't it made that way? Thanks for any hints. Best, Boris -- Boris Lau Albert-Ludwigs-University Freiburg Institute of Computer Science, Autonomous Intelligent Systems Group Georges-Koehler-Allee 079, D-79110 Freiburg, Germany Building 079, Room 1005 Phone: +49 761 203-8012 | Mobile: +49 174 9436758 http://www.informatik.uni-freiburg.de/~lau