The commands in the remainder of the book should be run as the
            root user. Check that ${CLFS} is
            set in the root user’s
            environment before proceeding.
          
          When the kernel boots the system, it requires the presence of a few
          device nodes, in particular the console and null
          devices. The device nodes will be created on the hard disk so that
          they are available before udev has been started, and
          additionally when Linux is started in single user mode (hence the
          restrictive permissions on console).
          Create these by running the following commands:
        
mknod -m 600 ${CLFS}/dev/console c 5 1
mknod -m 666 ${CLFS}/dev/null c 1 3
        
          Before udev starts, a tmpfs filesystem is mounted over /dev and the previous entries are no longer
          available. The following command creates files that are copied over
          by the udev bootscript:
        
mknod -m 600 ${CLFS}/lib/udev/devices/console c 5 1
mknod -m 666 ${CLFS}/lib/udev/devices/null c 1 3