Updated: 2022/Sep/29

Please read Privacy Policy. It's for your privacy.

CHPASS(1)                   General Commands Manual                  CHPASS(1)

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

     chpass [-a list] [-s newshell] [-l] [user]
     chpass [-a list] [-s newshell] [-y] [user]

     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.

     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.

     -s      The -s option attempts to change the user's shell to newshell.

     -l      This option causes the password to be updated only in the local
             password file.  When changing only the local password,
             pwd_mkdb(8) is used to update the password databases.

     -y      This forces the YP password database entry to be changed, even if
             the user has an entry in the local database.  The
             rpc.yppasswdd(8) daemon should be running on the YP master

     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
           Location:        user's normal location
           Home Phone:      user's home phone
           Office Phone:    user's office 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 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 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 is a key for a user's login class.  Login classes are
     defined in login.conf(5), which is a capfile(5) style database of user
     attributes, accounting, resource and environment settings.

     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.

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

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

     The vi(1) editor will be used unless the environment variable EDITOR is
     set to an alternative 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

     /etc/master.passwd  The user database
     /etc/passwd         A Version 7 format password file
     /etc/ptmp           Lock file for the passwd database
     /tmp/pw.XXXXXX      Temporary copy of the user passwd information
     /etc/shells         The list of approved shells

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

     Robert Morris and Ken Thompson, UNIX Password Security.

     The chpass command appeared in 4.3BSD-Reno.

     This program's interface is poorly suited to cryptographic systems such
     as Kerberos, and consequently Kerberos password changing is not a feature
     of this program.

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

NetBSD 10.99                     April 5, 2012                    NetBSD 10.99