Salut,
pourquoi vouloir modifier la structure de linux ????
il ne s'agit pas de modifier quoi que ce soit.
je l'appelerais plutôt personalisation de l'environnement perso
si on n'avait pas le droit de le faire ou si ce n'était pas conséillé alors on n'avait pas ce fichier
lami20j@debian:~$ cat /etc/default/useradd
# Default values for useradd(8)
#
# The SHELL variable specifies the default login shell on your
# system.
# Similar to DHSELL in adduser. We however use "sh" here because
# useradd being a low level utility should rather be as widely opened
# as possible
SHELL=/bin/sh
#
# The default group for users
# 1000=users on Debian systems
# same then USERS_GID in adduser
# Please be aware that Debian's adduser defaults to "user groups"
# which means that one group is created for each user
# There is no way to achieve this with useradd which must remains a low
# level utility
# GROUP=100
#
# The default home directory. Same than DHOME for adduser
# HOME=/home
#
# The number of days after a password expires until the account
# is permanently disabled
# INACTIVE=-1
#
# The default expire date
# EXPIRE=
#
# The SKEL variable specifies the directory containing "skeletal" user
# files; in other words, files such as a sample .profile that will be
# copied to the new user's home directory when it is created.
# SKEL=/etc/skel
#
# Defines whether the mail spool should be created while
# creating the account
# CREATE_MAIL_SPOOL=yes
lami20j@debian:~$
Le FHS ne changera pas. Il y aura toujours un répertoire home attaché à la racine, mais il ne sera pas utilisé
lami20j