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.
It is time to create some structure in the CLFS file system. Create a standard directory tree by issuing the following commands:
mkdir -pv ${CLFS}/{bin,boot,dev,{etc/,}opt,home,lib/firmware,mnt} mkdir -pv ${CLFS}/{proc,media/{floppy,cdrom},run/{,shm},sbin,srv,sys} mkdir -pv ${CLFS}/var/{lock,log,mail,spool} mkdir -pv ${CLFS}/var/{opt,cache,lib/{misc,locate},local} install -dv -m 0750 ${CLFS}/root install -dv -m 1777 ${CLFS}{/var,}/tmp ln -sv ../run ${CLFS}/var/run mkdir -pv ${CLFS}/usr/{,local/}{bin,include,lib,sbin,src} mkdir -pv ${CLFS}/usr/{,local/}share/{doc,info,locale,man} mkdir -pv ${CLFS}/usr/{,local/}share/{misc,terminfo,zoneinfo} mkdir -pv ${CLFS}/usr/{,local/}share/man/man{1,2,3,4,5,6,7,8}
Directories are, by default, created with permission mode 755, but
this is not desirable for all directories. In the commands above, two
changes are made—one to the home directory of user root
, and another to the directories for
temporary files.
The first mode change ensures that not just anybody can enter the
/root
directory—the same as a
normal user would do with his or her home directory. The second mode
change makes sure that any user can write to the /tmp
and /var/tmp
directories, but cannot remove another user's files from them. The
latter is prohibited by the so-called “sticky bit,” the highest bit (1) in the 1777 bit
mask.
The directory tree is based on the Filesystem Hierarchy Standard
(FHS) (available at https://wiki.linuxfoundation.org/en/FHS).
In addition to the tree created above, this standard stipulates the
existence of /usr/local/games
and
/usr/share/games
. The FHS is not
precise as to the structure of the /usr/local/share
subdirectory, so we create only
the directories that are needed. However, feel free to create these
directories if you prefer to conform more strictly to the FHS.