The x-kernel user must set up a ``build directory'' in which to construct an instance of the x-kernel . Build directories are usually created within a user's home directory.
Each build directory can support one x-kernel configuration at a time. The contents of three types of files determine an x-kernel configuration. They are:
The graph.comp file must reside in the build directory. Protocol table files and ROM files are not required to be in the build directory; later, we show how to specify the locations of these files. Note that the graph.comp file is read in during the build phase, and so represents an x-kernel 's static configuration. The protocol table files and ROM files are scanned at runtime, and so allow dynamic configuration of the x-kernel .
Directory /usr/xkernel/user_level/build/Template contains samples of common graph.comp and ROM files. The graph.comp file should be copied from this directory to your build directory. Also, the appropriate Makefile for your platform must be copied from this directory to the build directory; it should be renamed Makefile, and made writable. The sample ROM file found in this directory may be copied to a directory from which you intend to run the x-kernel ; more on this in Section 13.
For the purpose of the remaining discussion, we assume you are configuring a kernel so as to implement and evaluate protocol ASP (A Simple Protocol), the example protocol used in the x-kernel Tutorial [8].