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CHPASS(1) BSD General Commands Manual CHPASS(1)

NAME

chpass, chfn, chsh, — add or change user database information

SYNOPSIS

chpass [−a list] [−p encpass] [−e expiretime] [−s newshell] [user]

DESCRIPTION

The chpass utility allows editing of the user database information associated with user or, by default, the current user.

The chfn, and chsh utilities behave identically to chpass. (There is only one program.)

The information is formatted and supplied to an editor for changes.

Only the information that the user is allowed to change is displayed.

The options are as follows:

−a

The super-user is allowed to directly supply a user database entry, in the format specified by passwd(5), as an argument. This argument must be a colon (’’:’’) separated list of all the user database fields, although they may be empty. [Note that this only changes the user database, master.passwd.]

−p

The super-user is allowed to directly supply an encrypted password field, in the format used by crypt(3), as an argument. [See the discussion in getpwent(3) about types of passwords; this option may not be appropriate.]

−e expiretime

Change the account expire time. This option is used to set the expire time from a script as if it was done in the interactive editor.

−s newshell

Attempt to change the user’s shell to newshell.

Possible display items are as follows:

Login:

user’s login name

Password:

user’s encrypted password [do not use this to change a password; use passwd(1) instead]

Uid:

user’s login

Gid:

user’s login group

Class:

user’s general classification

Change:

password change time

Expire:

account expiration time

Full Name:

user’s real name (*)

Home Directory:

user’s home directory

Shell:

user’s login shell

NOTE(*) -

Historically, the so-call "GECOS" field in the user database entry contain the full name plus other information. Only the full name is currently supported.

The login field is the user name used to access the computer account.

The password field contains the encrypted form of the user’s password. Do not use this to change a password; use passwd(1) instead.

The uid field is the number associated with the login field. Both of these fields should be unique across the system (and often across a group of systems) as they control file access.

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.

The group field is the group that the user will be placed in at login. Since BSD supports multiple groups (see groups(1)) this field currently has little special meaning. This field may be filled in with either a number or a group name (see group(5)).

The class field references class descriptions in /etc/login.conf and is typically used to initialize the user’s system resource limits when they login.

The change field is the date by which the password must be changed.

The expire field is the date on which the account expires.

Both the change and expire fields should be entered in the form ’’month day year’’ where month is the month name (the first three characters are sufficient), day is the day of the month, and year is the year.

The full name field contains the full name of the user.

The user’s home directory is the full UNIX path name where the user will be placed at login.

The shell field is the command interpreter the user prefers. If the shell field is empty, the Bourne shell, /bin/sh, is assumed. When altering a login shell, and not the super-user, the user may not change from a non-standard shell or to a non-standard shell. Non-standard is defined as a shell not found in /etc/shells.

Once the information has been verified, chpass uses pwd_mkdb(8) to update the user database.

LOOKUPD AND DIRECTORY SERVICE AWARENESS

User database entries (among other things) are under the control of lookupd(8) and may be physically located in many different places, including local and remote netinfo(5) databases, directory service agents such as LDAP servers and flat file databases such as master.passwd. This version of chpass is currently limited to changing user database entries in the flat file and local netinfo databases.

ENVIRONMENT

The vi(1) editor will be used unless the environment variable EDITOR is set to an alternate editor. 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 with the user.

See pwd_mkdb(8) for an explanation of the impact of setting the PW_SCAN_BIG_IDS environment variable.

FILES
/etc/master.passwd

the user database

/etc/passwd

a Version 7 format password file

/etc/chpass.XXXXXX

temporary copy of the password file

/etc/shells

the list of approved shells

SEE ALSO

finger(1), login(1), passwd(1), getusershell(3), login.conf(5), passwd(5), pwd_mkdb(8), vipw(8)

and

Robert Morris and
Ken Thompson ,
UNIX Password security
.

BUGS

User information should (and eventually will) be stored elsewhere.

HISTORY

The chpass utility appeared in 4.3BSD−Reno.

BSD December 30, 1993 BSD