To configure an automated build, you have to use make. If you're using a managed project, you have to use GNU Make Builder, which generates the Makefiles for you. If the projects don't have any dependencies, you only have to run make in a root directory (or another appropriate directory). If you need to build several projects, you have to create an external Makefile that references all projects.
-source -a +inc -b -mydir +src +out Makefile
In this example, we're working in a directory called mydir, where you can run make, which allows us to run the make command to collect the libraries from other parts of the filesystem, and obtain the includes (including the local ones from the mydir directory).
In the Includes tab, select GNU C from the languages list, then click Add to select a directory (e.g., /source/a/inc) as your include path.
This step is required for the internal parser, for code navigation, refactoring, syntax highlighting, and more.