Hi Daniel, getState() is telling you the state of the client's current goal, not the state of the server. Hence, if there is no goal, getState is meaningless. This makes sense because a server could have the ability to handle multiple goals in parallel. Hence, there isn't a single state for the server that you can query. I imagine that what you are trying to do is determine if a server that can only handle a single goal is currently busy. I don't think that there is a general answer to that question. Some servers might reject your goal if they are already busy. Others might interrupt the existing goal. Let's see what others have to reply. Blaise On Fri, Oct 22, 2010 at 12:51 AM, Daniel Stonier wrote: > > Just a quick question with regards to the simple action client - why is > using the getState() method considered improper when there is no goal > (action client outputs an ROS_ERROR when you do so). Is there another means > of querying the server to know whether it is currently handling a goal or > not? > Or perhaps, am I mistaken in thinking that I should be needing to? > Regards, > Daniel Stonier. > -- > Phone : +82-10-5400-3296 (010-5400-3296) > Home: http://snorriheim.dnsdojo.com/ > Yujin Robot: http://www.yujinrobot.com/ > Eros: http://www.ros.org/wiki/eros > Embedded Control Libraries: http://snorriheim.dnsdojo.com/redmine/wiki/ecl > > _______________________________________________ > ros-users mailing list > ros-users@code.ros.org > https://code.ros.org/mailman/listinfo/ros-users > >