> The problem is that any change i do in the code does not make any difference
> in the behavior of the node.

When I read this, my first thought is: are you 100% sure you are
actually running your modified code? Did you run make? Is roslaunch
pulling your package from the wrong place? (If you have a package you
installed from a debian, and an overlay that you made your changes in,
are you quite sure that the shell you are roslaunching from has your
version of the package in ROS_PACKAGE_PATH? You can try using roscd
from the shell you are roslaunching from to see where roslaunch is
finding your package.)

Have you tried putting some ROS_INFO commands in your code to make
sure they get displayed wher you run it?

Blaise