Proper Shutdown handling of node
I have problems shutting down my nodes correctly. Se the following minimal example:
int main(int argc, char **argv)
{
ros::init(argc, argv, "mec_sensor_node");
ros::NodeHandle _oNH;
while (ros::ok()) {}
ROS_WARN("Test");
return 0;
}
If I kill the node (CTRL+C or rosnode kill) the node quits immediately without giving me the chance to do any cleanup. So my question is, how can I achieve this functionality? Using signals is a problem, because I need a function callback. So I thought killing the node makes ros::ok() to fail, such that the node finishes, but that isn't the case, as can be seen via the ROS_WARN command. Any odeas?
EDIT 1:
int main(int argc, char **argv)
{
ros::init(argc, argv, "mec_sensor_node");
ros::NodeHandle _oNH;
ros::spinOnce();
ros::Rate _oLoopRate(10);
while (ros::ok())
{
_oLoopRate.sleep();
}
ROS_WARN("Test");
return 0;
}
Why is it an issue to have a function callback ?
This may be a minimal example, but just to note: without a sleep or
ros::Ratein there, this is consuming 100% of your cpu, even when doing nothing.I also don't see a
ros::spinOnce(), so ROS has no way of processing events. That may be the cause of your issues.@Delb: Probably it may not be an issue, but I couldn't make it to pass a pointer to a signal_handler function. Could you provide a minimal example?
@gvdhoorn: I know about the resource problem, just deleted the content to reduce the code, but do you think that this regards my problem directly? However I edited the minimal example, but have the same problem.
I would have provided a similar example as @gvdhoorn 's link I think this is what you are looking for, and as he said if
ros::ok()returnsfalsethe connection to the master are dropped (see #q253661 )@gvdhoorn: Now I see, I couldn't use the ros logging system. Printing with cout shows that ros works as intended. Thank you very much for your help.