.\" Copyright (c) 1988 The Regents of the University of California.
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.\" @(#)chpass.1 5.4 (Berkeley) %G%
chpass \- add or change user database information
allows editing of the user database information associated
or, by default, the current user.
The information is formatted and supplied to an editor for changes.
editor will be used unless the environmental variable EDITOR indicates
When the editor terminates, the information is re-read and used to
update the user database itself.
Only the user, or the super-user, may edit the information associated
Only the information that the user is allowed to change is displayed.
Possible display items are as follows:
Gid: user's login group id
Change: password change time
Expire: account expiration time
Class: user's general classification
Home Directory: user's home directory
Shell: user's login shell
Full Name: user's real name
Location: user's normal location
Home Phone: user's home phone
Office Phone: user's office phone
field is the login used to access the computer account, and the
field is the number associated with it. They should both be unique
across the system (and often across a group of systems) since they
While it is possible to have multiple entries with identical login names
and/or identical user id's, it is usually a mistake to do so. Routines
that manipulate these files will often return only one of the multiple
entries, and that one by random selection.
field is the group that the user will be placed in upon login.
Since this system supports multiple groups (see
this field currently has little special meaning.
This field may be filled in with either a number or a group name (see
field is the date by which the password must be changed.
field is the date on which the account expires.
fields should be entered in the form ``month dd yy'' where
is the month name (the first three characters are sufficient),
is the day of the month, and
Also, either field may be ``none'' which will disable password
field is currently unused. In the near future it will be a key to
style database of user attributes.
The string ``none'' is the default for not belonging to any
The user's home directory is the full UNIX path name where the user
The shell field is the command interpreter the user prefers.
field is empty, the Bourne shell (\fI/bin/sh\fP) is assumed.
When altering a login shell, and not the super-user, the user must
select an approved shell from the list in
The last four fields are for storing the user's full name, office
location, and home and work telephone numbers.
Additions to the user database will be given an illegal passwd
(``NOLOGIN'') which should be updated using the
Once the information has been verified,
to update the user database. This is run in the background, and,
at very large sites could take several minutes. Until this update
is completed, the password file is unavailable for other updates
and the new information will not be available to programs.
/etc/master.passwd The user database
/etc/shells The list of approved shells
login(1), finger(1), getusershell(3), passwd(5), mkpasswd(8), vipw(8)
Robert Morris and Ken Thompson,
.I UNIX password security
User information should (and eventually will) be stored elsewhere.
projects / unix-history / blob