Specific Build Options

This section provides further information on directories and files already discussed in this Chapter.

Rebuilding a Component

You can delete any of the directories that were created in your work directory during the generation process. If the directory is necessary, the make command will rebuild it. For example, you can remove the BSP component, which in the examples above provides support for the PowerPC board. Then use the make command, which will regenerate the component, if it is necessary.

host% rm -rf build-BSP/ 
host% make build

The DONE File

When a component is compiled correctly, its Makefile.src file creates a file called DONE, in the build directory. The DONE file exists to prevent make from entering a component's build directory when there is nothing else to compile. If you run the make command, and the Makefile.src file has already created the DONE file, nothing will happen. These DONE files must be removed if a component has been modified, and the dependent components need to be relinked.

Remove the DONE file for the NUCLEUS component:

host% rm -f build-NUCLEUS/DONE

Run make now and it will enter the NUCLEUS component. Run the make command a second time and you will get no output, as the DONE file has again been created.

Rebuild of the conf Directory

To return to a previous configuration, remove the conf directory, or some files from the conf directory. This returns the system to the default configuration or to the configuration that you updated in the source configuration files. Even if you have not altered the configuration you can rebuild the conf files as follows:

host% rm -rf conf/
host% make xml