adduser - procedure for adding new users
A new user must choose a login name, which must not already appear in
/etc/passwd. An account can be added by editing a line into the passwd
file; this must be done with the password file locked e.g. by using
A new user is given a group and user id. User id's should be distinct
across a system, since they are used to control access to files. Typi-
cally, users working on similar projects will be put in the same group.
Thus at UCB we have groups for system staff, faculty, graduate stu-
dents, and a few special groups for large projects. System staff is
group "10" for historical reasons, and the super-user is in this group.
A skeletal account for a new user "ernie" would look like:
The first field is the login name "ernie". The next field is the
encrypted password which is not given and must be initialized using
passwd(1). The next two fields are the user and group id's. Tradi-
tionally, users in group 20 are graduate students and have account
names with numbers in the 200's. The next field gives information
about ernie's real name, office and office phone and home phone. This
information is used by the finger(1) program. From this information we
can tell that ernie's real name is "Ernie Kovacs" (the & here serves to
repeat "ernie" with appropriate capitalization), that his office is 508
Evans Hall, his extension is x2-7925, and this his home phone number is
642-8202. You can modify the finger(1) program if necessary to allow
different information to be encoded in this field. The UCB version of
finger knows several things particular to Berkeley - that phone exten-
sions start "2-", that offices ending in "E" are in Evans Hall and that
offices ending in "C" are in Cory Hall.
The final two fields give a login directory and a login shell name.
Traditionally, user files live on a file system which has the machines
single letter net(1) address as the first of two characters. Thus on
the Berkeley CS Department VAX, whose Berknet address is ``csvax''
abbreviated ``v'' the user file systems are mounted on ``/va'',
``/vb'', etc. On each such filesystem there are subdirectories there
for each group of users, i.e.: "/va/staff" and "/vb/prof". This is not
strictly necessary but keeps the number of files in the top level
directories reasonably small.
The login shell will default to "/bin/sh" if none is given. Most users
at Berkeley choose "/bin/csh" so this is usually specified here.
It is useful to give new users some help in getting started, supplying
them with a few skeletal files such as .profile if they use "/bin/sh",
or .cshrc and .login if they use "/bin/csh". The directory "/usr/skel"
contains skeletal definitions of such files. New users should be given
copies of these files which, for instance, arrange to use tset(1) auto-
matically at each login.
/etc/passwd password file
/usr/skel skeletal login directory
passwd(1), finger(1), chsh(1), chfn(1), passwd(5), vipw(8)
User information should be stored in its own data base separate from
the password file.
4th Berkeley Distribution 4 February 1983 ADDUSER(8)