In this post, we will see what the ROS workspace directories src, build and devel contain. We’ll also see how these directories are used in ROS workspace management.
Step 1: Create a Project (ROSject) on ROSDS
Head to http://rosds.online and create a project called “ros workspace” (or whatever you wish). Please ensure you select “Ubuntu 16.04 + ROS Kinetic + Gazebo 7” under “Configuration”. Once done with that, open up the project by clicking on “Open ROSject”.
Step 2: Check out what we have in the
catkin_ws workspace and save its current state in git
Pick a Shell tool from the Tools menu and locate the
user:~$ cd catkin_ws/ user:~/catkin_ws$ ll total 24 drwxrwxr-x 5 user user 4096 Jun 11 2018 ./ drwxrwxrwx 10 user user 4096 Dec 2 12:16 ../ -rw-rw-r-- 1 user user 98 Nov 17 2017 .catkin_workspace drwxrwxr-x 7 user user 4096 Jun 11 2018 build/ drwxrwxr-x 3 user user 4096 Jun 11 2018 devel/ drwxrwxr-x 2 user user 4096 Nov 17 2017 src/
So we see that we have three subfolders in the workspace: src, build and devel. Now we are going to save the current state of that directory before we make further changes:
user:~/catkin_ws$ git init Initialized empty Git repository in /home/user/catkin_ws/.git/ user:~/catkin_ws$ git add . user:~/catkin_ws$ git commit -m "Initial workspace state" [master (root-commit) d18311c] Initial workspace state 112 files changed, 7467 insertions(+) create mode 100644 .catkin_workspace ...# truncated messages user:~/catkin_ws$ git status On branch master nothing to commit, working tree clean
Step 3: Create a new package in the workspace and observe the changes
Take note that only the
src folder has been changed here.
# We change the workspace's src folder and create a package. user:~/catkin_ws$ cd src user:~/catkin_ws/src$ catkin_create_pkg test_package rospy Created file test_package/package.xml Created file test_package/CMakeLists.txt Created folder test_package/src Successfully created files in /home/user/catkin_ws/src/test_package. Please adjust the values in package.xml. # We change back to the workspace (catkin_ws) directory and see that we have new untracked files and directories. # We commit them to git. user:~/catkin_ws/src$ cd .. user:~/catkin_ws$ git status On branch master Untracked files: (use "git add <file>..." to include in what will be committed) src/test_package/ nothing added to commit but untracked files present (use "git add" to track) user:~/catkin_ws$ git add src/test_package/ user:~/catkin_ws$ git commit -m "Create a test package" [master 13e3e91] Create a test package 2 files changed, 266 insertions(+) create mode 100644 src/test_package/CMakeLists.txt create mode 100644 src/test_package/package.xml # We check the workspace folder again in git and see that it's "clean" user:~/catkin_ws$ git status On branch master nothing to commit, working tree clean user:~/catkin_ws$
Step 4: Compile the workspace and observe the changes
Now we will compile the workspace and see what happens.
# COMPILE THE WORKSPACE user:~/catkin_ws$ catkin_make Base path: /home/user/catkin_ws Source space: /home/user/catkin_ws/src Build space: /home/user/catkin_ws/build Devel space: /home/user/catkin_ws/devel Install space: /home/user/catkin_ws/install #### #### Running command: "cmake /home/user/catkin_ws/src -DCATKIN_DEVEL_PREFIX=/home/user/catkin_ws/devel -DCMAKE_INSTALL_PREFIX=/home/user/catkin_ws/install -G Unix Makefiles" in "/home/user/catkin_ws/build" #### #...lots of truncated messages # CHECK THE WORKSPACE IN GIT user:~/catkin_ws$ git status On branch master Changes not staged for commit: (use "git add <file>..." to update what will be committed) (use "git restore <file>..." to discard changes in working directory) modified: build/CMakeCache.txt modified: build/CMakeFiles/Makefile.cmake modified: build/CMakeFiles/Makefile2 modified: build/CMakeFiles/TargetDirectories.txt modified: build/CTestTestfile.cmake modified: build/Makefile modified: build/catkin/catkin_generated/version/package.cmake modified: build/catkin_generated/generate_cached_setup.py modified: build/catkin_generated/installspace/_setup_util.py modified: build/catkin_generated/installspace/setup.sh modified: build/catkin_generated/order_packages.cmake modified: build/catkin_generated/order_packages.py modified: build/catkin_generated/setup_cached.sh modified: build/catkin_generated/stamps/Project/_setup_util.py.stamp modified: build/catkin_generated/stamps/Project/package.xml.stamp modified: build/catkin_make.cache modified: build/cmake_install.cmake modified: devel/_setup_util.py modified: devel/setup.sh Untracked files: (use "git add <file>..." to include in what will be committed) build/CTestConfiguration.ini build/CTestCustom.cmake build/atomic_configure/ build/catkin_generated/installspace/local_setup.bash build/catkin_generated/installspace/local_setup.sh build/catkin_generated/installspace/local_setup.zsh build/test_package/ devel/cmake.lock devel/lib/ devel/local_setup.bash devel/local_setup.sh devel/local_setup.zsh devel/share/ no changes added to commit (use "git add" and/or "git commit -a")
Now we see that there a lot of modified and new files in both
devel, (no) thanks to the command we just ran.
Let’s put it all together in the next step.
Step 5: Put it all together – translate the action into words
I strongly believe you already got some hints about the src, build and devel directories from the commands we ran in the steps above. Now let’s consolidate those hints:
srccontains the source files for packages created. That’s why we created a package in this folder in Step 3.
- we run
buildto build the packages in src. You can call it
cmake‘s working directory. You’ll also notice that the bulk of modified files are in this direction after we ran
- ROS places built files of the package in
develfor development/testing. Yep, and that’s why most of the files in this directory after
install– this folder will be created if you compile with the command catkin_make install. Try it out!
And…that was it!
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