useradd 谡 ִ 3 (丮) ̴
-/etc/default/useradd ->⺻ Ȩ丮 , ڵ...
-/etc/login.defs ->ο ݵ ϴ ..
-/etc/skel/ ->ο ڵ Ǵ 丮.
ο 뷫 Ʒ .
/etc/passwd /etc/shadow Ͽ ڸ ߰
ʾҴٸ, ڸ ϰ /etc/group Ͽ ߰
Ȩ 丮 ʾҴٸ /home/<ڸ> 丮
/etc/skel 丮 '/home/<ڸ> 丮
Ƿ, ڵ鿡 ְ ʹٸ /etc/skel 丮 ȴ.
߰ Ǵ 丮 Ʈ ۹̼ ϰ ʹٸ /etc/login.defs Ͽ umask ָ ȴ.
) UMASK 076ַ ̴ adduser Ǵ useradd ɾ ɼ
adduser -d <Ȩ 丮><ڸ> Ȩ 丮
adduser -u < id><ڸ> id ȣ ƴ Ƿ
adduser -g <><ڸ>
adduser -s < ϸ><ڸ> /bin/bash
userdel <ڸ>
groupdel <>
ɾ /etc/group, /etc/shadow, /etc/shadow Ȯغ شǴ Ǿ ̴. Ȩ 丮 ״ ̴. 丮 Ѳ ϰ ϸ userdel -r <ڸ> ϸ ȴ