Throughout this book, the environment variable LFS 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 LFS partition. Check that the LFS variable is set up properly with:
echo $LFS
Make sure the output shows the path to the LFS partition's mount
point, which is /mnt/lfs if the
provided example was followed. If the output is incorrect, the
variable can be set with:
export LFS=/mnt/lfs
Having this variable set is beneficial in that commands such as mkdir $LFS/tools can be typed literally. The shell will automatically replace “$LFS” with “/mnt/lfs” (or whatever the variable was set to) when it processes the command line.
Do not forget to check that $LFS is set
whenever you leave and reenter the current working environment (as
when doing a su to
root or another user).