CHPASS(1)

NAME
chpass, chfn, chsh - add or change user database information

SYNOPSIS
chpass [-s newshell] [user]
chpass -a list

DESCRIPTION
chpass allows editing of the user database information associated with user, or, by default, the current user. The information is formatted and supplied to an editor for changes.

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

chfn and chsh are synonyms for chpass.

The options are as follows:

-a list
    The superuser 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.

-s newshell
    Attempts to change the user's shell to newshell.

Possible display items are as follows:

Login:
    user's login name
Password:
    user's encrypted password
Uid:
    user's login
Gid:
    user's login group
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
Office Location:
    user's office location
Office Phone:
    user's office phone
Home Phone:
    user's home phone

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.

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 IDs, 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 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 class field specifies a key in the login.conf(5) database of login class attributes. If empty, the “default” record is used.

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 superuser, 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.

The last four fields are for storing the user's full name, office location, and work and home telephone numbers.

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

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 superuser, may edit the information associated with the user.

FILES
/etc/master.passwd
    user database
/etc/passwd
    user database, with confidential information removed
/etc/ptmp
    lock file for the passwd database
/etc/shells
    list of approved shells
/var/tmp/pw.XXXXXXXXXX
    temporary copy of the user passwd information

DIAGNOSTICS

Attempting to lock password file, please wait or press ^C to abort

The password file is currently locked by another process; chpass will keep trying to lock the password file until it succeeds or the user hits the interrupt character (control-C by default). If chpass is interrupted while trying to gain the lock any changes made will be lost.

If the process holding the lock was prematurely terminated the lock file may be stale and chpass will wait forever trying to lock the password file. To determine whether a live process is actually holding the lock, the admin may run the following:

    $ fstat /etc/ptmp

If no process is listed, it is safe to remove the /etc/ptmp file to clear the error.

SEE ALSO
finger(1), login(1), passwd(1), getusershell(3), login.conf(5), passwd(5), pwd_mkdb(8), vipw(8) Robert Morris, Ken Thompson, Password security: a case history, Communications of the ACM, Volume 22, Issue 11, Nov. 1979, 594–597.

HISTORY
The chpass command appeared in 4.3BSD Reno.