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.\"	@(#)chpass.1	5.1 (Berkeley) %G%
.\"
.TH CHPASS 1 ""
.UC 4
.SH NAME
chpass \- add or change user database information
.SH SYNOPSIS
.B chpass
[ user ]
.SH DESCRIPTION
.I Chpass
allows editing of the user database information associated
with
.I user
or, by default, the current user.
The information is formatted and supplied to an editor for changes.
The
.I vi
editor will be used unless the environmental variable EDITOR indicates
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.
.PP
Only the information that the user is allowed to change is displayed.
.PP
When altering a login shell, and not the super-user, the user must
select an approved shell from the list in
.IR /etc/shells .
.PP
Additions to the user database will be given an illegal passwd
(``NOLOGIN'') which should be updated using the
.IR passwd (1)
program.
.PP
Once the information has been verified,
.I chpass
uses
.IR mkpasswd (8)
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.
.SH FILES
.DT
/etc/master.passwd		The user database
/etc/shells			The list of approved shells
.RE
.SH "SEE ALSO"
login(1), finger(1), getusershell(3), passwd(5), mkpasswd(8), vipw(8)
.br
Robert Morris and Ken Thompson,
.I UNIX password security