3.2. Adding the CLFS User

When logged in as user root, making a single mistake can damage or destroy a system. Therefore, we recommend building the packages as an unprivileged user. You could use your own user name, but to make it easier to set up a clean work environment, create a new user called clfs as a member of a new group (also named clfs) and use this user during the installation process. You may need to do this as the root user:

sudo groupadd clfs
sudo useradd -s /bin/bash -g clfs -m -k /dev/null clfs

The meaning of the command line options:

-s /bin/bash

This makes bash the default shell for user clfs.

-g clfs

This option adds user clfs to group clfs.


This creates a home directory for clfs.

-k /dev/null

This parameter prevents possible copying of files from a skeleton directory (default is /etc/skel) by changing the input location to the special null device.


This is the actual name for the created group and user.

To log in as clfs (as opposed to switching to user clfs when logged in as root, which does not require the clfs user to have a password), give clfs a password. You may need to do this as the root user:

sudo passwd clfs

Grant clfs full access to ${CLFS} by making clfs the directory's owner. You may need to do this as the root user:

sudo chown -Rv clfs ${CLFS}

Next, login as user clfs. This can be done via a virtual console, through a display manager, or with the following substitute user command:

su - clfs

The “-” instructs su to start a login shell as opposed to a non-login shell. The difference between these two types of shells can be found in detail in bash(1) and info bash.