How to link a common module in more packages?

Question

Hello,

I have some ROS C++ packages that share many common functions.

They are identical functions so I was thinking to put them all in another file.hpp and include this file in each package is needing them.

I'm using catkin to create my workspace and all the packages I develop. They are all in src directory starting from the main one, as the tutorials said.

But where do I must save this file.hpp in the workspace and which path I have to #include in each file that is using it? Do I have to modify the CMakeLists.txt?

This is a scheme of my workspace:

• build

• devel

• src

  package 1

  CMakeLists.txt

  src (file.cpp are here)

  include

  package1.xml

  package 2

  ...

Thanks in advance.

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Originally posted by eds on ROS Answers with karma: 101 on 2013-12-11

Post score: 0

Answer 1

The library package @dornhege recommends should be built like this:

• http://docs.ros.org/api/catkin/html/howto/building_libraries.html

If you only provide headers and no libraries, skip the library build and installation instructions. But, you should install the headers.

You other packages will reference it like this:

• http://docs.ros.org/api/catkin/html/howto/catkin_library_dependencies.html

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Originally posted by joq with karma: 25443 on 2013-12-12

This answer was ACCEPTED on the original site

Post score: 2

Answer 2

The ROS way would be to create a package for these common functions. The common code goes in there either as a header or built as a library.

All other packages that need this would then just depend on this package.

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Originally posted by dornhege with karma: 31395 on 2013-12-11

This answer was NOT ACCEPTED on the original site

Post score: 2

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Original comments

Comment by eds on 2013-12-12:
Thank you, can you make an example? I can create a package but how do I must make the others dependable by this one? Do I have to put some extra #include, CMakeLists or package.xml statement?