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Correct way of modifying ROS classes? (do I have to edit installed headers directly?)

asked 2012-07-07 10:49:50 -0500

rob20 gravatar image

updated 2012-07-07 23:30:12 -0500

Goal: Add a new member function in callback_queue.cpp from roscpp (ros_comm stack)

Problem: make error "no member function declared in class ‘ros::CallbackQueue’"

Details: To get the roscpp source, I followed the instructions to build from source (

I added my new member function in /home/xyz/ros-underlay/ros_comm/clients/cpp/roscpp/src/libros/callback_queue.cpp and declared it in /home/xyz/ros-underlay/ros_comm/clients/cpp/roscpp/include/ros/callback_queue.h

However, when performing (in /home/xyz/ros-underlay/build)

cmake .. -DCMAKE_INSTALL_PREFIX=/opt/ros/fuerte
make -j8

I get the error

error: no ‘void ros::CallbackQueue::my_new_func()’ member function declared
in class ‘ros::CallbackQueue’

I can get rid of this error by editing the already installed header file (/opt/ros/fuerte/include/ros/callback_queue.h) and declaring the new member function there. However I guess it's not the recommended approach to work directly on the installed header files, instead of those in /home/xyz/ros_underlay (?).

-> So my question is what is the correct approach when I want to perform some edits in ROS files like callback_queue.cpp? Should I somehow tell make (or CMakelists.txt) to use the headers in /home/xyz/ros-underlay/ros_comm/clients/cpp/roscpp/include/ros instead?

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I'm somewhat surprised make isn't already using the headers that go along with the sources you configured as opposed to the ones in /opt/ros ... Is catkin/cmake setting the include directories to /opt/ros (or otherwise your ROS_PACKAGE_PATH) and putting those before the headers in your source build?

Eric Perko gravatar image Eric Perko  ( 2012-07-08 08:43:04 -0500 )edit

Maybe you could try make -j1 VERBOSE=1 to get more verbose output and include the make line for callback_queue.cpp here so we can take a look at the include paths that the compiler is using.

Eric Perko gravatar image Eric Perko  ( 2012-07-08 08:43:56 -0500 )edit

2 Answers

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answered 2012-07-07 23:23:09 -0500

rob20 gravatar image

updated 2012-07-08 06:31:05 -0500

Thanks joq, but that did not solve the issue: I still have to edit the installed header file (as opposed to the header file in the source tree), and I don't think that's a good way (?). The only thing that using -DCMAKE_INSTALL_PREFIX changed was that the installation is now in my home directory instead of /opt/ros/fuerte.


According to your suggestion, I created a new install subdir /home/xyz/ros-underlay/install, and then, from /home/xyz/ros-underlay, called

cmake .. -DCMAKE_INSTALL_PREFIX=../install
make -j8
sudo make install

For the first sudo make install I could run make to have my modified callback_queue compiled. But for subsequent changes, I get the same make error as in my original question, and I can only get rid of it by editing the installed header file in /home/xyz/ros-underlay/install, instead of the "source" version in /home/xyz/ros-underlay/ros_comm/clients/cpp/roscpp/include/ros.

P.S. I wanted to post this as a comment to your answer, but there was no comment field (I only see comment fields under my own posts so far).

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This is too long to be a comment. You should update your original question to include this additional information. That's also better than using an answer for something too long for a comment so that it doesn't get re-ordered in the future as answers get sorted by votes/date/etc

Eric Perko gravatar image Eric Perko  ( 2012-07-08 08:39:23 -0500 )edit

answered 2012-07-07 14:21:12 -0500

joq gravatar image

Try setting a different CMAKE_INSTALL_PREFIX.

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Asked: 2012-07-07 10:49:50 -0500

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Last updated: Jul 08 '12