%general-entities; ]> Throughout this book, the environment variable CLFS will be used several times. It is paramount that this variable is always defined. It should be set to the mount point chosen for the CLFS partition. Check that the CLFS variable is set up properly with: echo $CLFS Make sure the output shows the path to the CLFS partition's mount point, which is /mnt/clfs if the provided example was followed. If the output is incorrect, the variable can be set with: export CLFS=/mnt/clfs Having this variable set is beneficial in that commands such as install -d $CLFS/tools can be typed literally. The shell will automatically replace $CLFS with /mnt/clfs (or whatever the variable was set to) when it processes the command line. If you haven't created the $CLFS directory, do so at this time by issuing the following commands: install -dv $CLFS Do not forget to check that $CLFS is set whenever you leave and reenter the current working environment (as when doing a su to root or another user).