The ``C'' target is enabled with the command-line option -tc.
Instead of using the u32 classifier for the if construct, ``C'' writes the corresponding expression in the C language to a file, and generates a kernel module for it. The resulting custom-built classifier should be much more efficient than a classifier using u32.
The commands to load the kernel module are issued on standard output, along with the tc commands, so the same scripts as for the ``tc'' target can be used.